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On Friday, October 13, 2023, 17:40, Dave Casey <polara413@...> wrote:

Walt -

Is the 20 Mhz BW Limit pushbutton (located directly above the Ch2 Volts/Div knob) depressed? If it is not depressed, perhaps the switch has gotten dirty and cycling it a few times will resolve your issue?

Dave Casey

On Fri, Oct 13, 2023 at 3:25?PM Walt KA2NJF via <wmilton2359=[email protected]> wrote:

Hey,?

I just joined the group and my name is Walter, KA2NJF I am 80 years old. My Tektronix is in need of service. Is there any service deposit or any one in the South Jersey or South East PA who works on this piece of equipment? I can not get any frequency reading above 20 MHZ and this is a 150 MHZ scope.?

Thanks,?

Walt, KA2NJF?

On 10/13/2023 8:07 PM, Walt KA2NJF via groups.io wrote:

Davy,

I have tried recycling all the switches, push buttons, and rotary switches with no change in the Tek 2445 response. I even looked for a master reset switch. I have tried recycling the push buttons, switchs and rotary switches on and off for the past three or four days. The last time I remember it working was a month or so ago. If you come up with any more suggestions I am all ears.

Thanks,
Walt, KA2NJF


Sent from the all new AOL app for iOS <>

On Friday, October 13, 2023, 17:40, Dave Casey <polara413@...> wrote:

Walt -

Is the 20 Mhz BW Limit pushbutton (located directly above the Ch2
Volts/Div knob) depressed? If it is not depressed, perhaps the
switch has gotten dirty and cycling it a few times will resolve
your issue?

Dave Casey

On Fri, Oct 13, 2023 at 3:25?PM Walt KA2NJF via groups.io
<> <wmilton2359@...> wrote:

Hey,

I just joined the group and my name is Walter, KA2NJF I am 80
years old. My Tektronix is in need of service. Is there any
service deposit or any one in the South Jersey or South East
PA who works on this piece of equipment? I can not get any
frequency reading above 20 MHZ and this is a 150 MHZ scope.

Thanks,
Walt, KA2NJF


Sent from the all new AOL app for iOS
<>

On Friday, October 13, 2023, 21:45, Harvey White <madyn@...> wrote:

Take a 20 Mhz square wave and look at it on 20 Mhz bandwidth, then go to
full bandwidth.? If that doesn't give two different results, then that
tells you a lot.

Harvey


On 10/13/2023 8:07 PM, Walt KA2NJF via groups.io wrote:
> Davy,
>
> I have tried recycling all the switches, push buttons, and rotary
> switches with no change in the Tek 2445 response. I even looked for a
> master reset switch. I have tried recycling the push buttons, switchs
> and rotary switches on and off for the past three or four days. The
> last time I remember it working was a month or so ago. If you come up
> with any more suggestions I am all ears.
>
> Thanks,
> Walt, KA2NJF
>
>
> Sent from the all new AOL app for iOS
> <>
>
> On Friday, October 13, 2023, 17:40, Dave Casey <polara413@...>
> wrote:
>
>? ? Walt -
>
>? ? Is the 20 Mhz BW Limit pushbutton (located directly above the Ch2
>? ? Volts/Div knob) depressed? If it is not depressed, perhaps the
>? ? switch has gotten dirty and cycling it a few times will resolve
>? ? your issue?
>
>? ? Dave Casey
>
>? ? On Fri, Oct 13, 2023 at 3:25?PM Walt KA2NJF via groups.io
>? ? <> <wmilton2359@...> wrote:
>
>? ? ? ? Hey,
>
>? ? ? ? I just joined the group and my name is Walter, KA2NJF I am 80
>? ? ? ? years old. My Tektronix is in need of service. Is there any
>? ? ? ? service deposit or any one in the South Jersey or South East
>? ? ? ? PA who works on this piece of equipment? I can not get any
>? ? ? ? frequency reading above 20 MHZ and this is a 150 MHZ scope.
>
>? ? ? ? Thanks,
>? ? ? ? Walt, KA2NJF
>
>
>? ? ? ? Sent from the all new AOL app for iOS
>? ? ? ? <>
>
>

On 10/13/2023 11:33 PM, Walt KA2NJF via groups.io wrote:

Harvey,

At the present time I have nothing to generate a 20 MHZ signal with. Will it work with a 20 MHZ RF signal ??

Walt


Sent from the all new AOL app for iOS <>

On Friday, October 13, 2023, 21:45, Harvey White <madyn@...> wrote:

Take a 20 Mhz square wave and look at it on 20 Mhz bandwidth, then
go to
full bandwidth.? If that doesn't give two different results, then
that
tells you a lot.

Harvey


On 10/13/2023 8:07 PM, Walt KA2NJF via groups.io wrote:
> Davy,
>
> I have tried recycling all the switches, push buttons, and rotary
> switches with no change in the Tek 2445 response. I even looked
for a
> master reset switch. I have tried recycling the push buttons,
switchs
> and rotary switches on and off for the past three or four days. The
> last time I remember it working was a month or so ago. If you
come up
> with any more suggestions I am all ears.
>
> Thanks,
> Walt, KA2NJF
>
>
> Sent from the all new AOL app for iOS
>
<>
>
> On Friday, October 13, 2023, 17:40, Dave Casey
<polara413@...>
> wrote:
>
>? ? Walt -
>
>? ? Is the 20 Mhz BW Limit pushbutton (located directly above the Ch2
>? ? Volts/Div knob) depressed? If it is not depressed, perhaps the
>? ? switch has gotten dirty and cycling it a few times will resolve
>? ? your issue?
>
>? ? Dave Casey
>
>? ? On Fri, Oct 13, 2023 at 3:25?PM Walt KA2NJF via groups.io
>? ? <> <wmilton2359@...> wrote:
>
>? ? ? ? Hey,
>
>? ? ? ? I just joined the group and my name is Walter, KA2NJF I am 80
>? ? ? ? years old. My Tektronix is in need of service. Is there any
>? ? ? ? service deposit or any one in the South Jersey or South East
>? ? ? ? PA who works on this piece of equipment? I can not get any
>? ? ? ? frequency reading above 20 MHZ and this is a 150 MHZ scope.
>
>? ? ? ? Thanks,
>? ? ? ? Walt, KA2NJF
>
>
>? ? ? ? Sent from the all new AOL app for iOS
>? ? ? ?
<>
>
>

On Saturday, October 14, 2023, 00:34, Harvey White <madyn@...> wrote:

I'd say anything between 10 and 20.? What you're looking for is the
effect of the 20 Mhz bandwidth reduction.? The higher the frequency, the
more obvious.

Do NOT couple a transmitter directly into the scope, use a dummy load on
the transmitter, and pick up a signal with a wire loop. SA's and Scopes
cannot tolerate wattage from a transformer.? You could use a 5 Mhz
square wave and look for the edge to see how it changes, that works, too.

Harvey


On 10/13/2023 11:33 PM, Walt KA2NJF via groups.io wrote:
> Harvey,
>
> At the present time I have nothing to generate a 20 MHZ signal with.
> Will it work with a 20 MHZ RF signal ??
>
> Walt
>
>
> Sent from the all new AOL app for iOS
> <>
>
> On Friday, October 13, 2023, 21:45, Harvey White
> <madyn@...> wrote:
>
>? ? Take a 20 Mhz square wave and look at it on 20 Mhz bandwidth, then
>? ? go to
>? ? full bandwidth.? If that doesn't give two different results, then
>? ? that
>? ? tells you a lot.
>
>? ? Harvey
>
>
>? ? On 10/13/2023 8:07 PM, Walt KA2NJF via groups.io wrote:
>? ? > Davy,
>? ? >
>? ? > I have tried recycling all the switches, push buttons, and rotary
>? ? > switches with no change in the Tek 2445 response. I even looked
>? ? for a
>? ? > master reset switch. I have tried recycling the push buttons,
>? ? switchs
>? ? > and rotary switches on and off for the past three or four days. The
>? ? > last time I remember it working was a month or so ago. If you
>? ? come up
>? ? > with any more suggestions I am all ears.
>? ? >
>? ? > Thanks,
>? ? > Walt, KA2NJF
>? ? >
>? ? >
>? ? > Sent from the all new AOL app for iOS
>? ? >
>? ? <>
>? ? >
>? ? > On Friday, October 13, 2023, 17:40, Dave Casey
>? ? <polara413@...>
>? ? > wrote:
>? ? >
>? ? >? ? Walt -
>? ? >
>? ? >? ? Is the 20 Mhz BW Limit pushbutton (located directly above the Ch2
>? ? >? ? Volts/Div knob) depressed? If it is not depressed, perhaps the
>? ? >? ? switch has gotten dirty and cycling it a few times will resolve
>? ? >? ? your issue?
>? ? >
>? ? >? ? Dave Casey
>? ? >
>? ? >? ? On Fri, Oct 13, 2023 at 3:25?PM Walt KA2NJF via groups.io
>? ? >? ? <> <wmilton2359@...> wrote:
>? ? >
>? ? >? ? ? ? Hey,
>? ? >
>? ? >? ? ? ? I just joined the group and my name is Walter, KA2NJF I am 80
>? ? >? ? ? ? years old. My Tektronix is in need of service. Is there any
>? ? >? ? ? ? service deposit or any one in the South Jersey or South East
>? ? >? ? ? ? PA who works on this piece of equipment? I can not get any
>? ? >? ? ? ? frequency reading above 20 MHZ and this is a 150 MHZ scope.
>? ? >
>? ? >? ? ? ? Thanks,
>? ? >? ? ? ? Walt, KA2NJF
>? ? >
>? ? >
>? ? >? ? ? ? Sent from the all new AOL app for iOS
>? ? >? ? ? ?
>? ? <>
>? ? >
>? ? >
>
>
>
>
>
>

On 10/14/2023 12:02 PM, Walt KA2NJF via groups.io wrote:

Harvey,

The test equipment I have is:
1. Wavetek Signal Generator
2. HP 410C VTVM
3. Sinometer Frequency Counter
4. Tel 2445 Scope

It looks like I will have to purchase some more equipment if funds let me !!
I will remove the case and blow out the dust and look at the fan. I will reoil it if possible.
I don’t have a service manual.

Walt


Sent from the all new AOL app for iOS <>

On Saturday, October 14, 2023, 00:34, Harvey White <madyn@...> wrote:

I'd say anything between 10 and 20.? What you're looking for is the
effect of the 20 Mhz bandwidth reduction.? The higher the
frequency, the
more obvious.

Do NOT couple a transmitter directly into the scope, use a dummy
load on
the transmitter, and pick up a signal with a wire loop. SA's and
Scopes
cannot tolerate wattage from a transformer.? You could use a 5 Mhz
square wave and look for the edge to see how it changes, that
works, too.

Harvey


On 10/13/2023 11:33 PM, Walt KA2NJF via groups.io wrote:
> Harvey,
>
> At the present time I have nothing to generate a 20 MHZ signal
with.
> Will it work with a 20 MHZ RF signal ??
>
> Walt
>
>
> Sent from the all new AOL app for iOS
>
<>
>
> On Friday, October 13, 2023, 21:45, Harvey White
> <madyn@...> wrote:
>
>? ? Take a 20 Mhz square wave and look at it on 20 Mhz bandwidth,
then
>? ? go to
>? ? full bandwidth.? If that doesn't give two different results, then
>? ? that
>? ? tells you a lot.
>
>? ? Harvey
>
>
>? ? On 10/13/2023 8:07 PM, Walt KA2NJF via groups.io wrote:
>? ? > Davy,
>? ? >
>? ? > I have tried recycling all the switches, push buttons, and
rotary
>? ? > switches with no change in the Tek 2445 response. I even looked
>? ? for a
>? ? > master reset switch. I have tried recycling the push buttons,
>? ? switchs
>? ? > and rotary switches on and off for the past three or four
days. The
>? ? > last time I remember it working was a month or so ago. If you
>? ? come up
>? ? > with any more suggestions I am all ears.
>? ? >
>? ? > Thanks,
>? ? > Walt, KA2NJF
>? ? >
>? ? >
>? ? > Sent from the all new AOL app for iOS
>? ? >
>? ?
<>
>? ? >
>? ? > On Friday, October 13, 2023, 17:40, Dave Casey
>? ? <polara413@...>
>? ? > wrote:
>? ? >
>? ? >? ? Walt -
>? ? >
>? ? >? ? Is the 20 Mhz BW Limit pushbutton (located directly
above the Ch2
>? ? >? ? Volts/Div knob) depressed? If it is not depressed,
perhaps the
>? ? >? ? switch has gotten dirty and cycling it a few times will
resolve
>? ? >? ? your issue?
>? ? >
>? ? >? ? Dave Casey
>? ? >
>? ? >? ? On Fri, Oct 13, 2023 at 3:25?PM Walt KA2NJF via groups.io
>? ? >? ? <> <wmilton2359@...>
wrote:
>? ? >
>? ? >? ? ? ? Hey,
>? ? >
>? ? >? ? ? ? I just joined the group and my name is Walter,
KA2NJF I am 80
>? ? >? ? ? ? years old. My Tektronix is in need of service. Is
there any
>? ? >? ? ? ? service deposit or any one in the South Jersey or
South East
>? ? >? ? ? ? PA who works on this piece of equipment? I can not
get any
>? ? >? ? ? ? frequency reading above 20 MHZ and this is a 150 MHZ
scope.
>? ? >
>? ? >? ? ? ? Thanks,
>? ? >? ? ? ? Walt, KA2NJF
>? ? >
>? ? >
>? ? >? ? ? ? Sent from the all new AOL app for iOS
>? ? >
>? ?
<>
>? ? >
>? ? >
>
>
>
>
>
>

On Saturday, October 14, 2023, 13:51, Harvey White <madyn@...> wrote:

Ok, how fast is the wavetek signal generator?

if it's at least 2 mhz, and can put out a square wave, then try that.?
You're looking for significant edge rounding at any frequency from 2 Mhz
on (the higher, the more rounding) in the 20 Mhz position.? You need
about 10x the bandwidth to reproduce a decent square wave.? i.e. 2 Mhz
needs 20 Mhz bandwidth because of the harmonics that make the square
wave square.? That's why I suggested something around 10 to 20 Mhz.?
You'd be able to see the effects.? The closer to the 2 Mhz you get (and
below), the less you'll see the effect of the bandwidth.

See if tek WIKI has the service manual.

If you can breadboard a TTL oscillator, that might help.? Same
restrictions on frequency.

Harvey


On 10/14/2023 12:02 PM, Walt KA2NJF via groups.io wrote:
> Harvey,
>
> The test equipment I have is:
> 1. Wavetek Signal Generator
> 2. HP 410C VTVM
> 3. Sinometer Frequency Counter
> 4. Tel 2445 Scope
>
> It looks like I will have to purchase some more equipment if funds let
> me !!
> I will remove the case and blow out the dust and look at the fan. I
> will reoil it if possible.
> I don’t have a service manual.
>
> Walt
>
>
> Sent from the all new AOL app for iOS
> <>
>
> On Saturday, October 14, 2023, 00:34, Harvey White
> <madyn@...> wrote:
>
>? ? I'd say anything between 10 and 20.? What you're looking for is the
>? ? effect of the 20 Mhz bandwidth reduction.? The higher the
>? ? frequency, the
>? ? more obvious.
>
>? ? Do NOT couple a transmitter directly into the scope, use a dummy
>? ? load on
>? ? the transmitter, and pick up a signal with a wire loop. SA's and
>? ? Scopes
>? ? cannot tolerate wattage from a transformer.? You could use a 5 Mhz
>? ? square wave and look for the edge to see how it changes, that
>? ? works, too.
>
>? ? Harvey
>
>
>? ? On 10/13/2023 11:33 PM, Walt KA2NJF via groups.io wrote:
>? ? > Harvey,
>? ? >
>? ? > At the present time I have nothing to generate a 20 MHZ signal
>? ? with.
>? ? > Will it work with a 20 MHZ RF signal ??
>? ? >
>? ? > Walt
>? ? >
>? ? >
>? ? > Sent from the all new AOL app for iOS
>? ? >
>? ? <>
>? ? >
>? ? > On Friday, October 13, 2023, 21:45, Harvey White
>? ? > <madyn@...> wrote:
>? ? >
>? ? >? ? Take a 20 Mhz square wave and look at it on 20 Mhz bandwidth,
>? ? then
>? ? >? ? go to
>? ? >? ? full bandwidth.? If that doesn't give two different results, then
>? ? >? ? that
>? ? >? ? tells you a lot.
>? ? >
>? ? >? ? Harvey
>? ? >
>? ? >
>? ? >? ? On 10/13/2023 8:07 PM, Walt KA2NJF via groups.io wrote:
>? ? >? ? > Davy,
>? ? >? ? >
>? ? >? ? > I have tried recycling all the switches, push buttons, and
>? ? rotary
>? ? >? ? > switches with no change in the Tek 2445 response. I even looked
>? ? >? ? for a
>? ? >? ? > master reset switch. I have tried recycling the push buttons,
>? ? >? ? switchs
>? ? >? ? > and rotary switches on and off for the past three or four
>? ? days. The
>? ? >? ? > last time I remember it working was a month or so ago. If you
>? ? >? ? come up
>? ? >? ? > with any more suggestions I am all ears.
>? ? >? ? >
>? ? >? ? > Thanks,
>? ? >? ? > Walt, KA2NJF
>? ? >? ? >
>? ? >? ? >
>? ? >? ? > Sent from the all new AOL app for iOS
>? ? >? ? >
>? ? >? ?
>? ? <>
>? ? >? ? >
>? ? >? ? > On Friday, October 13, 2023, 17:40, Dave Casey
>? ? >? ? <polara413@...>
>? ? >? ? > wrote:
>? ? >? ? >
>? ? >? ? >? ? Walt -
>? ? >? ? >
>? ? >? ? >? ? Is the 20 Mhz BW Limit pushbutton (located directly
>? ? above the Ch2
>? ? >? ? >? ? Volts/Div knob) depressed? If it is not depressed,
>? ? perhaps the
>? ? >? ? >? ? switch has gotten dirty and cycling it a few times will
>? ? resolve
>? ? >? ? >? ? your issue?
>? ? >? ? >
>? ? >? ? >? ? Dave Casey
>? ? >? ? >
>? ? >? ? >? ? On Fri, Oct 13, 2023 at 3:25?PM Walt KA2NJF via groups.io
>? ? >? ? >? ? <> <wmilton2359@...>
>? ? wrote:
>? ? >? ? >
>? ? >? ? >? ? ? ? Hey,
>? ? >? ? >
>? ? >? ? >? ? ? ? I just joined the group and my name is Walter,
>? ? KA2NJF I am 80
>? ? >? ? >? ? ? ? years old. My Tektronix is in need of service. Is
>? ? there any
>? ? >? ? >? ? ? ? service deposit or any one in the South Jersey or
>? ? South East
>? ? >? ? >? ? ? ? PA who works on this piece of equipment? I can not
>? ? get any
>? ? >? ? >? ? ? ? frequency reading above 20 MHZ and this is a 150 MHZ
>? ? scope.
>? ? >? ? >
>? ? >? ? >? ? ? ? Thanks,
>? ? >? ? >? ? ? ? Walt, KA2NJF
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >? ? ? ? Sent from the all new AOL app for iOS
>? ? >? ? >
>? ? >? ?
>? ? <>
>? ? >? ? >
>? ? >? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>
>
>
>
>
>

On 10/15/2023 12:19 PM, Walt KA2NJF via groups.io wrote:

Harvey,

My WaveTek does not support square wave generation.

Walt


Sent from the all new AOL app for iOS <>

On Saturday, October 14, 2023, 13:51, Harvey White <madyn@...> wrote:

Ok, how fast is the wavetek signal generator?

if it's at least 2 mhz, and can put out a square wave, then try that.
You're looking for significant edge rounding at any frequency from
2 Mhz
on (the higher, the more rounding) in the 20 Mhz position. You need
about 10x the bandwidth to reproduce a decent square wave. i.e. 2 Mhz
needs 20 Mhz bandwidth because of the harmonics that make the square
wave square.? That's why I suggested something around 10 to 20 Mhz.
You'd be able to see the effects.? The closer to the 2 Mhz you get
(and
below), the less you'll see the effect of the bandwidth.

See if tek WIKI has the service manual.

If you can breadboard a TTL oscillator, that might help. Same
restrictions on frequency.

Harvey


On 10/14/2023 12:02 PM, Walt KA2NJF via groups.io wrote:
> Harvey,
>
> The test equipment I have is:
> 1. Wavetek Signal Generator
> 2. HP 410C VTVM
> 3. Sinometer Frequency Counter
> 4. Tel 2445 Scope
>
> It looks like I will have to purchase some more equipment if
funds let
> me !!
> I will remove the case and blow out the dust and look at the fan. I
> will reoil it if possible.
> I don’t have a service manual.
>
> Walt
>
>
> Sent from the all new AOL app for iOS
>
<>
>
> On Saturday, October 14, 2023, 00:34, Harvey White
> <madyn@...> wrote:
>
>? ? I'd say anything between 10 and 20.? What you're looking for
is the
>? ? effect of the 20 Mhz bandwidth reduction.? The higher the
>? ? frequency, the
>? ? more obvious.
>
>? ? Do NOT couple a transmitter directly into the scope, use a dummy
>? ? load on
>? ? the transmitter, and pick up a signal with a wire loop. SA's and
>? ? Scopes
>? ? cannot tolerate wattage from a transformer.? You could use a
5 Mhz
>? ? square wave and look for the edge to see how it changes, that
>? ? works, too.
>
>? ? Harvey
>
>
>? ? On 10/13/2023 11:33 PM, Walt KA2NJF via groups.io wrote:
>? ? > Harvey,
>? ? >
>? ? > At the present time I have nothing to generate a 20 MHZ signal
>? ? with.
>? ? > Will it work with a 20 MHZ RF signal ??
>? ? >
>? ? > Walt
>? ? >
>? ? >
>? ? > Sent from the all new AOL app for iOS
>? ? >
>? ?
<>
>? ? >
>? ? > On Friday, October 13, 2023, 21:45, Harvey White
>? ? > <madyn@...> wrote:
>? ? >
>? ? >? ? Take a 20 Mhz square wave and look at it on 20 Mhz
bandwidth,
>? ? then
>? ? >? ? go to
>? ? >? ? full bandwidth.? If that doesn't give two different
results, then
>? ? >? ? that
>? ? >? ? tells you a lot.
>? ? >
>? ? >? ? Harvey
>? ? >
>? ? >
>? ? >? ? On 10/13/2023 8:07 PM, Walt KA2NJF via groups.io wrote:
>? ? >? ? > Davy,
>? ? >? ? >
>? ? >? ? > I have tried recycling all the switches, push buttons, and
>? ? rotary
>? ? >? ? > switches with no change in the Tek 2445 response. I
even looked
>? ? >? ? for a
>? ? >? ? > master reset switch. I have tried recycling the push
buttons,
>? ? >? ? switchs
>? ? >? ? > and rotary switches on and off for the past three or four
>? ? days. The
>? ? >? ? > last time I remember it working was a month or so ago.
If you
>? ? >? ? come up
>? ? >? ? > with any more suggestions I am all ears.
>? ? >? ? >
>? ? >? ? > Thanks,
>? ? >? ? > Walt, KA2NJF
>? ? >? ? >
>? ? >? ? >
>? ? >? ? > Sent from the all new AOL app for iOS
>? ? >? ? >
>? ? >
>? ?
<>
>? ? >? ? >
>? ? >? ? > On Friday, October 13, 2023, 17:40, Dave Casey
>? ? >? ? <polara413@...>
>? ? >? ? > wrote:
>? ? >? ? >
>? ? >? ? >? ? Walt -
>? ? >? ? >
>? ? >? ? >? ? Is the 20 Mhz BW Limit pushbutton (located directly
>? ? above the Ch2
>? ? >? ? >? ? Volts/Div knob) depressed? If it is not depressed,
>? ? perhaps the
>? ? >? ? >? ? switch has gotten dirty and cycling it a few times will
>? ? resolve
>? ? >? ? >? ? your issue?
>? ? >? ? >
>? ? >? ? >? ? Dave Casey
>? ? >? ? >
>? ? >? ? >? ? On Fri, Oct 13, 2023 at 3:25?PM Walt KA2NJF via
groups.io
>? ? >? ? >? ? <> <wmilton2359@...>
>? ? wrote:
>? ? >? ? >
>? ? >? ? >? ? ? ? Hey,
>? ? >? ? >
>? ? >? ? >? ? ? ? I just joined the group and my name is Walter,
>? ? KA2NJF I am 80
>? ? >? ? >? ? ? ? years old. My Tektronix is in need of service. Is
>? ? there any
>? ? >? ? >? ? ? ? service deposit or any one in the South Jersey or
>? ? South East
>? ? >? ? >? ? ? ? PA who works on this piece of equipment? I can not
>? ? get any
>? ? >? ? >? ? ? ? frequency reading above 20 MHZ and this is a
150 MHZ
>? ? scope.
>? ? >? ? >
>? ? >? ? >? ? ? ? Thanks,
>? ? >? ? >? ? ? ? Walt, KA2NJF
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >? ? ? ? Sent from the all new AOL app for iOS
>? ? >? ? >
>? ? >
>? ?
<>
>? ? >? ? >
>? ? >? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>
>
>
>
>
>

On Sunday, October 15, 2023, 12:44, Harvey White <madyn@...> wrote:

Can you breadboard TTL?

1K in series, 5.0 volt P-P sine wave, diodes to VCC and GND to limit
what the gate input sees, use any schmidt trigger (74LS14, etc) to
produce a pulse output, then run that through a few gates (same package)
to neaten it up, and you have an emergency square wave generator.

Harvey


On 10/15/2023 12:19 PM, Walt KA2NJF via groups.io wrote:
> Harvey,
>
> My WaveTek does not support square wave generation.
>
> Walt
>
>
> Sent from the all new AOL app for iOS
> <>
>
> On Saturday, October 14, 2023, 13:51, Harvey White
> <madyn@...> wrote:
>
>? ? Ok, how fast is the wavetek signal generator?
>
>? ? if it's at least 2 mhz, and can put out a square wave, then try that.
>? ? You're looking for significant edge rounding at any frequency from
>? ? 2 Mhz
>? ? on (the higher, the more rounding) in the 20 Mhz position. You need
>? ? about 10x the bandwidth to reproduce a decent square wave. i.e. 2 Mhz
>? ? needs 20 Mhz bandwidth because of the harmonics that make the square
>? ? wave square.? That's why I suggested something around 10 to 20 Mhz.
>? ? You'd be able to see the effects.? The closer to the 2 Mhz you get
>? ? (and
>? ? below), the less you'll see the effect of the bandwidth.
>
>? ? See if tek WIKI has the service manual.
>
>? ? If you can breadboard a TTL oscillator, that might help. Same
>? ? restrictions on frequency.
>
>? ? Harvey
>
>
>? ? On 10/14/2023 12:02 PM, Walt KA2NJF via groups.io wrote:
>? ? > Harvey,
>? ? >
>? ? > The test equipment I have is:
>? ? > 1. Wavetek Signal Generator
>? ? > 2. HP 410C VTVM
>? ? > 3. Sinometer Frequency Counter
>? ? > 4. Tel 2445 Scope
>? ? >
>? ? > It looks like I will have to purchase some more equipment if
>? ? funds let
>? ? > me !!
>? ? > I will remove the case and blow out the dust and look at the fan. I
>? ? > will reoil it if possible.
>? ? > I don’t have a service manual.
>? ? >
>? ? > Walt
>? ? >
>? ? >
>? ? > Sent from the all new AOL app for iOS
>? ? >
>? ? <>
>? ? >
>? ? > On Saturday, October 14, 2023, 00:34, Harvey White
>? ? > <madyn@...> wrote:
>? ? >
>? ? >? ? I'd say anything between 10 and 20.? What you're looking for
>? ? is the
>? ? >? ? effect of the 20 Mhz bandwidth reduction.? The higher the
>? ? >? ? frequency, the
>? ? >? ? more obvious.
>? ? >
>? ? >? ? Do NOT couple a transmitter directly into the scope, use a dummy
>? ? >? ? load on
>? ? >? ? the transmitter, and pick up a signal with a wire loop. SA's and
>? ? >? ? Scopes
>? ? >? ? cannot tolerate wattage from a transformer.? You could use a
>? ? 5 Mhz
>? ? >? ? square wave and look for the edge to see how it changes, that
>? ? >? ? works, too.
>? ? >
>? ? >? ? Harvey
>? ? >
>? ? >
>? ? >? ? On 10/13/2023 11:33 PM, Walt KA2NJF via groups.io wrote:
>? ? >? ? > Harvey,
>? ? >? ? >
>? ? >? ? > At the present time I have nothing to generate a 20 MHZ signal
>? ? >? ? with.
>? ? >? ? > Will it work with a 20 MHZ RF signal ??
>? ? >? ? >
>? ? >? ? > Walt
>? ? >? ? >
>? ? >? ? >
>? ? >? ? > Sent from the all new AOL app for iOS
>? ? >? ? >
>? ? >? ?
>? ? <>
>? ? >? ? >
>? ? >? ? > On Friday, October 13, 2023, 21:45, Harvey White
>? ? >? ? > <madyn@...> wrote:
>? ? >? ? >
>? ? >? ? >? ? Take a 20 Mhz square wave and look at it on 20 Mhz
>? ? bandwidth,
>? ? >? ? then
>? ? >? ? >? ? go to
>? ? >? ? >? ? full bandwidth.? If that doesn't give two different
>? ? results, then
>? ? >? ? >? ? that
>? ? >? ? >? ? tells you a lot.
>? ? >? ? >
>? ? >? ? >? ? Harvey
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >? ? On 10/13/2023 8:07 PM, Walt KA2NJF via groups.io wrote:
>? ? >? ? >? ? > Davy,
>? ? >? ? >? ? >
>? ? >? ? >? ? > I have tried recycling all the switches, push buttons, and
>? ? >? ? rotary
>? ? >? ? >? ? > switches with no change in the Tek 2445 response. I
>? ? even looked
>? ? >? ? >? ? for a
>? ? >? ? >? ? > master reset switch. I have tried recycling the push
>? ? buttons,
>? ? >? ? >? ? switchs
>? ? >? ? >? ? > and rotary switches on and off for the past three or four
>? ? >? ? days. The
>? ? >? ? >? ? > last time I remember it working was a month or so ago.
>? ? If you
>? ? >? ? >? ? come up
>? ? >? ? >? ? > with any more suggestions I am all ears.
>? ? >? ? >? ? >
>? ? >? ? >? ? > Thanks,
>? ? >? ? >? ? > Walt, KA2NJF
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? > Sent from the all new AOL app for iOS
>? ? >? ? >? ? >
>? ? >? ? >
>? ? >? ?
>? ? <>
>? ? >? ? >? ? >
>? ? >? ? >? ? > On Friday, October 13, 2023, 17:40, Dave Casey
>? ? >? ? >? ? <polara413@...>
>? ? >? ? >? ? > wrote:
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? Walt -
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? Is the 20 Mhz BW Limit pushbutton (located directly
>? ? >? ? above the Ch2
>? ? >? ? >? ? >? ? Volts/Div knob) depressed? If it is not depressed,
>? ? >? ? perhaps the
>? ? >? ? >? ? >? ? switch has gotten dirty and cycling it a few times will
>? ? >? ? resolve
>? ? >? ? >? ? >? ? your issue?
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? Dave Casey
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? On Fri, Oct 13, 2023 at 3:25?PM Walt KA2NJF via
>? ? groups.io
>? ? >? ? >? ? >? ? <> <wmilton2359@...>
>? ? >? ? wrote:
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? ? ? Hey,
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? ? ? I just joined the group and my name is Walter,
>? ? >? ? KA2NJF I am 80
>? ? >? ? >? ? >? ? ? ? years old. My Tektronix is in need of service. Is
>? ? >? ? there any
>? ? >? ? >? ? >? ? ? ? service deposit or any one in the South Jersey or
>? ? >? ? South East
>? ? >? ? >? ? >? ? ? ? PA who works on this piece of equipment? I can not
>? ? >? ? get any
>? ? >? ? >? ? >? ? ? ? frequency reading above 20 MHZ and this is a
>? ? 150 MHZ
>? ? >? ? scope.
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? ? ? Thanks,
>? ? >? ? >? ? >? ? ? ? Walt, KA2NJF
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? ? ? Sent from the all new AOL app for iOS
>? ? >? ? >? ? >
>? ? >? ? >
>? ? >? ?
>? ? <>
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>
>
>
>
>
>

On 10/15/2023 3:20 PM, Walt KA2NJF via groups.io wrote:

Harvey,

Can you draw that up for me. I have to be very careful since my right hand shakes when it wants to. I do have a plug in breadboard that I can use. The Schmidt trigger chip I will look a see if I have any. If not then I will purchase some.

Walt


Sent from the all new AOL app for iOS <>

On Sunday, October 15, 2023, 12:44, Harvey White <madyn@...> wrote:

Can you breadboard TTL?

1K in series, 5.0 volt P-P sine wave, diodes to VCC and GND to limit
what the gate input sees, use any schmidt trigger (74LS14, etc) to
produce a pulse output, then run that through a few gates (same
package)
to neaten it up, and you have an emergency square wave generator.

Harvey


On 10/15/2023 12:19 PM, Walt KA2NJF via groups.io wrote:
> Harvey,
>
> My WaveTek does not support square wave generation.
>
> Walt
>
>
> Sent from the all new AOL app for iOS
>
<>
>
> On Saturday, October 14, 2023, 13:51, Harvey White
> <madyn@...> wrote:
>
>? ? Ok, how fast is the wavetek signal generator?
>
>? ? if it's at least 2 mhz, and can put out a square wave, then
try that.
>? ? You're looking for significant edge rounding at any frequency
from
>? ? 2 Mhz
>? ? on (the higher, the more rounding) in the 20 Mhz position.
You need
>? ? about 10x the bandwidth to reproduce a decent square wave.
i.e. 2 Mhz
>? ? needs 20 Mhz bandwidth because of the harmonics that make the
square
>? ? wave square.? That's why I suggested something around 10 to
20 Mhz.
>? ? You'd be able to see the effects.? The closer to the 2 Mhz
you get
>? ? (and
>? ? below), the less you'll see the effect of the bandwidth.
>
>? ? See if tek WIKI has the service manual.
>
>? ? If you can breadboard a TTL oscillator, that might help. Same
>? ? restrictions on frequency.
>
>? ? Harvey
>
>
>? ? On 10/14/2023 12:02 PM, Walt KA2NJF via groups.io wrote:
>? ? > Harvey,
>? ? >
>? ? > The test equipment I have is:
>? ? > 1. Wavetek Signal Generator
>? ? > 2. HP 410C VTVM
>? ? > 3. Sinometer Frequency Counter
>? ? > 4. Tel 2445 Scope
>? ? >
>? ? > It looks like I will have to purchase some more equipment if
>? ? funds let
>? ? > me !!
>? ? > I will remove the case and blow out the dust and look at
the fan. I
>? ? > will reoil it if possible.
>? ? > I don’t have a service manual.
>? ? >
>? ? > Walt
>? ? >
>? ? >
>? ? > Sent from the all new AOL app for iOS
>? ? >
>? ?
<>
>? ? >
>? ? > On Saturday, October 14, 2023, 00:34, Harvey White
>? ? > <madyn@...> wrote:
>? ? >
>? ? >? ? I'd say anything between 10 and 20.? What you're looking for
>? ? is the
>? ? >? ? effect of the 20 Mhz bandwidth reduction. The higher the
>? ? >? ? frequency, the
>? ? >? ? more obvious.
>? ? >
>? ? >? ? Do NOT couple a transmitter directly into the scope, use
a dummy
>? ? >? ? load on
>? ? >? ? the transmitter, and pick up a signal with a wire loop.
SA's and
>? ? >? ? Scopes
>? ? >? ? cannot tolerate wattage from a transformer. You could use a
>? ? 5 Mhz
>? ? >? ? square wave and look for the edge to see how it changes,
that
>? ? >? ? works, too.
>? ? >
>? ? >? ? Harvey
>? ? >
>? ? >
>? ? >? ? On 10/13/2023 11:33 PM, Walt KA2NJF via groups.io wrote:
>? ? >? ? > Harvey,
>? ? >? ? >
>? ? >? ? > At the present time I have nothing to generate a 20
MHZ signal
>? ? >? ? with.
>? ? >? ? > Will it work with a 20 MHZ RF signal ??
>? ? >? ? >
>? ? >? ? > Walt
>? ? >? ? >
>? ? >? ? >
>? ? >? ? > Sent from the all new AOL app for iOS
>? ? >? ? >
>? ? >
>? ?
<>
>? ? >? ? >
>? ? >? ? > On Friday, October 13, 2023, 21:45, Harvey White
>? ? >? ? > <madyn@...> wrote:
>? ? >? ? >
>? ? >? ? >? ? Take a 20 Mhz square wave and look at it on 20 Mhz
>? ? bandwidth,
>? ? >? ? then
>? ? >? ? >? ? go to
>? ? >? ? >? ? full bandwidth.? If that doesn't give two different
>? ? results, then
>? ? >? ? >? ? that
>? ? >? ? >? ? tells you a lot.
>? ? >? ? >
>? ? >? ? >? ? Harvey
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >? ? On 10/13/2023 8:07 PM, Walt KA2NJF via groups.io wrote:
>? ? >? ? >? ? > Davy,
>? ? >? ? >? ? >
>? ? >? ? >? ? > I have tried recycling all the switches, push
buttons, and
>? ? >? ? rotary
>? ? >? ? >? ? > switches with no change in the Tek 2445 response. I
>? ? even looked
>? ? >? ? >? ? for a
>? ? >? ? >? ? > master reset switch. I have tried recycling the push
>? ? buttons,
>? ? >? ? >? ? switchs
>? ? >? ? >? ? > and rotary switches on and off for the past three
or four
>? ? >? ? days. The
>? ? >? ? >? ? > last time I remember it working was a month or so
ago.
>? ? If you
>? ? >? ? >? ? come up
>? ? >? ? >? ? > with any more suggestions I am all ears.
>? ? >? ? >? ? >
>? ? >? ? >? ? > Thanks,
>? ? >? ? >? ? > Walt, KA2NJF
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? > Sent from the all new AOL app for iOS
>? ? >? ? >? ? >
>? ? >? ? >
>? ? >
>? ?
<>
>? ? >? ? >? ? >
>? ? >? ? >? ? > On Friday, October 13, 2023, 17:40, Dave Casey
>? ? >? ? >? ? <polara413@...>
>? ? >? ? >? ? > wrote:
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? Walt -
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? Is the 20 Mhz BW Limit pushbutton (located
directly
>? ? >? ? above the Ch2
>? ? >? ? >? ? >? ? Volts/Div knob) depressed? If it is not depressed,
>? ? >? ? perhaps the
>? ? >? ? >? ? >? ? switch has gotten dirty and cycling it a few
times will
>? ? >? ? resolve
>? ? >? ? >? ? >? ? your issue?
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? Dave Casey
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? On Fri, Oct 13, 2023 at 3:25?PM Walt KA2NJF via
>? ? groups.io
>? ? >? ? >? ? >? ? <>
<wmilton2359@...>
>? ? >? ? wrote:
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? ? ? Hey,
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? ? ? I just joined the group and my name is Walter,
>? ? >? ? KA2NJF I am 80
>? ? >? ? >? ? >? ? ? ? years old. My Tektronix is in need of
service. Is
>? ? >? ? there any
>? ? >? ? >? ? >? ? ? ? service deposit or any one in the South
Jersey or
>? ? >? ? South East
>? ? >? ? >? ? >? ? ? ? PA who works on this piece of equipment? I
can not
>? ? >? ? get any
>? ? >? ? >? ? >? ? ? ? frequency reading above 20 MHZ and this is a
>? ? 150 MHZ
>? ? >? ? scope.
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? ? ? Thanks,
>? ? >? ? >? ? >? ? ? ? Walt, KA2NJF
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? ? ? Sent from the all new AOL app for iOS
>? ? >? ? >? ? >
>? ? >? ? >
>? ? >
>? ?
<>
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>
>
>
>
>
>

On 10/15/2023 4:06 PM, Tom Gardner wrote:

Something like this should be OK.


Make sure the IC is properly decoupled with minimal lead lengths.

The rule of thumb for the risetime of a scope/probe combination is
tr=0.35/BW, so a 100MHz scope should show a 3.5ns risetime.


On 15/10/2023, Walt KA2NJF via groups.io
<wmilton2359@...> wrote:

Harvey,
Can you draw that up for me. I have to be very careful since my right hand
shakes when it wants to. I do have a plug in breadboard that I can use. The
Schmidt trigger chip I will look a see if I have any. If not then I will
purchase some.
Walt


Sent from the all new AOL app for iOS


On Sunday, October 15, 2023, 12:44, Harvey White <madyn@...>
wrote:

Can you breadboard TTL?

1K in series, 5.0 volt P-P sine wave, diodes to VCC and GND to limit
what the gate input sees, use any schmidt trigger (74LS14, etc) to
produce a pulse output, then run that through a few gates (same package)
to neaten it up, and you have an emergency square wave generator.

Harvey

On Sunday, October 15, 2023, 16:42, Harvey White <madyn@...> wrote:

I can, but first, you realize that this is nothing more than a bandwidth
check and a very crude one?? Your function generator ought to go to to
10 Mhz or so.

If it does triangle waves, you can use a triangle instead of a square
(just different harmonics but still needs them).? If the triangle starts
to round with 20 Mhz bandwidth in, and is reasonably sharp at 20 Mhz
bandwidth out, then you've done the same thing.

If the bandwidth is limited, then you'll see that the triangle looks a
lot like a sine instead of a proper triangle.

You don't absolutely need a schmidt trigger, I'm just being a purist.

What PC board layout programs do you have?? They have schematic
capture.? Kicad is one.? I personally use an old version of EAGLE, so I
could deliver this to you as a picture without you having to do anything.

First, though, how high a frequency can your function generator do?

Harvey


On 10/15/2023 3:20 PM, Walt KA2NJF via groups.io wrote:
> Harvey,
>
> Can you draw that up for me. I have to be very careful since my right
> hand shakes when it wants to. I do have a plug in breadboard that I
> can use. The Schmidt trigger chip I will look a see if I have any. If
> not then I will purchase some.
>
> Walt
>
>
> Sent from the all new AOL app for iOS
> <>
>
> On Sunday, October 15, 2023, 12:44, Harvey White
> <madyn@...> wrote:
>
>? ? Can you breadboard TTL?
>
>? ? 1K in series, 5.0 volt P-P sine wave, diodes to VCC and GND to limit
>? ? what the gate input sees, use any schmidt trigger (74LS14, etc) to
>? ? produce a pulse output, then run that through a few gates (same
>? ? package)
>? ? to neaten it up, and you have an emergency square wave generator.
>
>? ? Harvey
>
>
>? ? On 10/15/2023 12:19 PM, Walt KA2NJF via groups.io wrote:
>? ? > Harvey,
>? ? >
>? ? > My WaveTek does not support square wave generation.
>? ? >
>? ? > Walt
>? ? >
>? ? >
>? ? > Sent from the all new AOL app for iOS
>? ? >
>? ? <>
>? ? >
>? ? > On Saturday, October 14, 2023, 13:51, Harvey White
>? ? > <madyn@...> wrote:
>? ? >
>? ? >? ? Ok, how fast is the wavetek signal generator?
>? ? >
>? ? >? ? if it's at least 2 mhz, and can put out a square wave, then
>? ? try that.
>? ? >? ? You're looking for significant edge rounding at any frequency
>? ? from
>? ? >? ? 2 Mhz
>? ? >? ? on (the higher, the more rounding) in the 20 Mhz position.
>? ? You need
>? ? >? ? about 10x the bandwidth to reproduce a decent square wave.
>? ? i.e. 2 Mhz
>? ? >? ? needs 20 Mhz bandwidth because of the harmonics that make the
>? ? square
>? ? >? ? wave square.? That's why I suggested something around 10 to
>? ? 20 Mhz.
>? ? >? ? You'd be able to see the effects.? The closer to the 2 Mhz
>? ? you get
>? ? >? ? (and
>? ? >? ? below), the less you'll see the effect of the bandwidth.
>? ? >
>? ? >? ? See if tek WIKI has the service manual.
>? ? >
>? ? >? ? If you can breadboard a TTL oscillator, that might help. Same
>? ? >? ? restrictions on frequency.
>? ? >
>? ? >? ? Harvey
>? ? >
>? ? >
>? ? >? ? On 10/14/2023 12:02 PM, Walt KA2NJF via groups.io wrote:
>? ? >? ? > Harvey,
>? ? >? ? >
>? ? >? ? > The test equipment I have is:
>? ? >? ? > 1. Wavetek Signal Generator
>? ? >? ? > 2. HP 410C VTVM
>? ? >? ? > 3. Sinometer Frequency Counter
>? ? >? ? > 4. Tel 2445 Scope
>? ? >? ? >
>? ? >? ? > It looks like I will have to purchase some more equipment if
>? ? >? ? funds let
>? ? >? ? > me !!
>? ? >? ? > I will remove the case and blow out the dust and look at
>? ? the fan. I
>? ? >? ? > will reoil it if possible.
>? ? >? ? > I don’t have a service manual.
>? ? >? ? >
>? ? >? ? > Walt
>? ? >? ? >
>? ? >? ? >
>? ? >? ? > Sent from the all new AOL app for iOS
>? ? >? ? >
>? ? >? ?
>? ? <>
>? ? >? ? >
>? ? >? ? > On Saturday, October 14, 2023, 00:34, Harvey White
>? ? >? ? > <madyn@...> wrote:
>? ? >? ? >
>? ? >? ? >? ? I'd say anything between 10 and 20.? What you're looking for
>? ? >? ? is the
>? ? >? ? >? ? effect of the 20 Mhz bandwidth reduction. The higher the
>? ? >? ? >? ? frequency, the
>? ? >? ? >? ? more obvious.
>? ? >? ? >
>? ? >? ? >? ? Do NOT couple a transmitter directly into the scope, use
>? ? a dummy
>? ? >? ? >? ? load on
>? ? >? ? >? ? the transmitter, and pick up a signal with a wire loop.
>? ? SA's and
>? ? >? ? >? ? Scopes
>? ? >? ? >? ? cannot tolerate wattage from a transformer. You could use a
>? ? >? ? 5 Mhz
>? ? >? ? >? ? square wave and look for the edge to see how it changes,
>? ? that
>? ? >? ? >? ? works, too.
>? ? >? ? >
>? ? >? ? >? ? Harvey
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >? ? On 10/13/2023 11:33 PM, Walt KA2NJF via groups.io wrote:
>? ? >? ? >? ? > Harvey,
>? ? >? ? >? ? >
>? ? >? ? >? ? > At the present time I have nothing to generate a 20
>? ? MHZ signal
>? ? >? ? >? ? with.
>? ? >? ? >? ? > Will it work with a 20 MHZ RF signal ??
>? ? >? ? >? ? >
>? ? >? ? >? ? > Walt
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? > Sent from the all new AOL app for iOS
>? ? >? ? >? ? >
>? ? >? ? >
>? ? >? ?
>? ? <>
>? ? >? ? >? ? >
>? ? >? ? >? ? > On Friday, October 13, 2023, 21:45, Harvey White
>? ? >? ? >? ? > <madyn@...> wrote:
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? Take a 20 Mhz square wave and look at it on 20 Mhz
>? ? >? ? bandwidth,
>? ? >? ? >? ? then
>? ? >? ? >? ? >? ? go to
>? ? >? ? >? ? >? ? full bandwidth.? If that doesn't give two different
>? ? >? ? results, then
>? ? >? ? >? ? >? ? that
>? ? >? ? >? ? >? ? tells you a lot.
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? Harvey
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? On 10/13/2023 8:07 PM, Walt KA2NJF via groups.io wrote:
>? ? >? ? >? ? >? ? > Davy,
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? > I have tried recycling all the switches, push
>? ? buttons, and
>? ? >? ? >? ? rotary
>? ? >? ? >? ? >? ? > switches with no change in the Tek 2445 response. I
>? ? >? ? even looked
>? ? >? ? >? ? >? ? for a
>? ? >? ? >? ? >? ? > master reset switch. I have tried recycling the push
>? ? >? ? buttons,
>? ? >? ? >? ? >? ? switchs
>? ? >? ? >? ? >? ? > and rotary switches on and off for the past three
>? ? or four
>? ? >? ? >? ? days. The
>? ? >? ? >? ? >? ? > last time I remember it working was a month or so
>? ? ago.
>? ? >? ? If you
>? ? >? ? >? ? >? ? come up
>? ? >? ? >? ? >? ? > with any more suggestions I am all ears.
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? > Thanks,
>? ? >? ? >? ? >? ? > Walt, KA2NJF
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? > Sent from the all new AOL app for iOS
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >
>? ? >? ?
>? ? <>
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? > On Friday, October 13, 2023, 17:40, Dave Casey
>? ? >? ? >? ? >? ? <polara413@...>
>? ? >? ? >? ? >? ? > wrote:
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? Walt -
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? Is the 20 Mhz BW Limit pushbutton (located
>? ? directly
>? ? >? ? >? ? above the Ch2
>? ? >? ? >? ? >? ? >? ? Volts/Div knob) depressed? If it is not depressed,
>? ? >? ? >? ? perhaps the
>? ? >? ? >? ? >? ? >? ? switch has gotten dirty and cycling it a few
>? ? times will
>? ? >? ? >? ? resolve
>? ? >? ? >? ? >? ? >? ? your issue?
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? Dave Casey
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? On Fri, Oct 13, 2023 at 3:25?PM Walt KA2NJF via
>? ? >? ? groups.io
>? ? >? ? >? ? >? ? >? ? <>
>? ? <wmilton2359@...>
>? ? >? ? >? ? wrote:
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? ? ? Hey,
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? ? ? I just joined the group and my name is Walter,
>? ? >? ? >? ? KA2NJF I am 80
>? ? >? ? >? ? >? ? >? ? ? ? years old. My Tektronix is in need of
>? ? service. Is
>? ? >? ? >? ? there any
>? ? >? ? >? ? >? ? >? ? ? ? service deposit or any one in the South
>? ? Jersey or
>? ? >? ? >? ? South East
>? ? >? ? >? ? >? ? >? ? ? ? PA who works on this piece of equipment? I
>? ? can not
>? ? >? ? >? ? get any
>? ? >? ? >? ? >? ? >? ? ? ? frequency reading above 20 MHZ and this is a
>? ? >? ? 150 MHZ
>? ? >? ? >? ? scope.
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? ? ? Thanks,
>? ? >? ? >? ? >? ? >? ? ? ? Walt, KA2NJF
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? ? ? Sent from the all new AOL app for iOS
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >
>? ? >? ?
>? ? <>
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>
>
>
>
>
>

On 10/15/2023 7:22 PM, Walt KA2NJF via groups.io wrote:

Harvey,

I don’t have a function generator. My WaveTek function generator does Just RF. Also I don’t have a cad program on hand.

I plan on taking the cover off the scope. I can then blow out the dust and see if I can apply some Deoxid D5 to the push buttons and switches.

Then I’ll see how high of a signal it will take. I have not seen any magic smoke leave the unit so my hopes are high. I will let you know how I make out.

Thanks for all your help and assistance !!

Walt


Sent from the all new AOL app for iOS <>

On Sunday, October 15, 2023, 16:42, Harvey White <madyn@...> wrote:

I can, but first, you realize that this is nothing more than a
bandwidth
check and a very crude one?? Your function generator ought to go
to to
10 Mhz or so.

If it does triangle waves, you can use a triangle instead of a square
(just different harmonics but still needs them).? If the triangle
starts
to round with 20 Mhz bandwidth in, and is reasonably sharp at 20 Mhz
bandwidth out, then you've done the same thing.

If the bandwidth is limited, then you'll see that the triangle
looks a
lot like a sine instead of a proper triangle.

You don't absolutely need a schmidt trigger, I'm just being a purist.

What PC board layout programs do you have?? They have schematic
capture.? Kicad is one.? I personally use an old version of EAGLE,
so I
could deliver this to you as a picture without you having to do
anything.

First, though, how high a frequency can your function generator do?

Harvey


On 10/15/2023 3:20 PM, Walt KA2NJF via groups.io wrote:
> Harvey,
>
> Can you draw that up for me. I have to be very careful since my
right
> hand shakes when it wants to. I do have a plug in breadboard that I
> can use. The Schmidt trigger chip I will look a see if I have
any. If
> not then I will purchase some.
>
> Walt
>
>
> Sent from the all new AOL app for iOS
>
<>
>
> On Sunday, October 15, 2023, 12:44, Harvey White
> <madyn@...> wrote:
>
>? ? Can you breadboard TTL?
>
>? ? 1K in series, 5.0 volt P-P sine wave, diodes to VCC and GND
to limit
>? ? what the gate input sees, use any schmidt trigger (74LS14,
etc) to
>? ? produce a pulse output, then run that through a few gates (same
>? ? package)
>? ? to neaten it up, and you have an emergency square wave generator.
>
>? ? Harvey
>
>
>? ? On 10/15/2023 12:19 PM, Walt KA2NJF via groups.io wrote:
>? ? > Harvey,
>? ? >
>? ? > My WaveTek does not support square wave generation.
>? ? >
>? ? > Walt
>? ? >
>? ? >
>? ? > Sent from the all new AOL app for iOS
>? ? >
>? ?
<>
>? ? >
>? ? > On Saturday, October 14, 2023, 13:51, Harvey White
>? ? > <madyn@...> wrote:
>? ? >
>? ? >? ? Ok, how fast is the wavetek signal generator?
>? ? >
>? ? >? ? if it's at least 2 mhz, and can put out a square wave, then
>? ? try that.
>? ? >? ? You're looking for significant edge rounding at any
frequency
>? ? from
>? ? >? ? 2 Mhz
>? ? >? ? on (the higher, the more rounding) in the 20 Mhz position.
>? ? You need
>? ? >? ? about 10x the bandwidth to reproduce a decent square wave.
>? ? i.e. 2 Mhz
>? ? >? ? needs 20 Mhz bandwidth because of the harmonics that
make the
>? ? square
>? ? >? ? wave square.? That's why I suggested something around 10 to
>? ? 20 Mhz.
>? ? >? ? You'd be able to see the effects.? The closer to the 2 Mhz
>? ? you get
>? ? >? ? (and
>? ? >? ? below), the less you'll see the effect of the bandwidth.
>? ? >
>? ? >? ? See if tek WIKI has the service manual.
>? ? >
>? ? >? ? If you can breadboard a TTL oscillator, that might help.
Same
>? ? >? ? restrictions on frequency.
>? ? >
>? ? >? ? Harvey
>? ? >
>? ? >
>? ? >? ? On 10/14/2023 12:02 PM, Walt KA2NJF via groups.io wrote:
>? ? >? ? > Harvey,
>? ? >? ? >
>? ? >? ? > The test equipment I have is:
>? ? >? ? > 1. Wavetek Signal Generator
>? ? >? ? > 2. HP 410C VTVM
>? ? >? ? > 3. Sinometer Frequency Counter
>? ? >? ? > 4. Tel 2445 Scope
>? ? >? ? >
>? ? >? ? > It looks like I will have to purchase some more
equipment if
>? ? >? ? funds let
>? ? >? ? > me !!
>? ? >? ? > I will remove the case and blow out the dust and look at
>? ? the fan. I
>? ? >? ? > will reoil it if possible.
>? ? >? ? > I don’t have a service manual.
>? ? >? ? >
>? ? >? ? > Walt
>? ? >? ? >
>? ? >? ? >
>? ? >? ? > Sent from the all new AOL app for iOS
>? ? >? ? >
>? ? >
>? ?
<>
>? ? >? ? >
>? ? >? ? > On Saturday, October 14, 2023, 00:34, Harvey White
>? ? >? ? > <madyn@...> wrote:
>? ? >? ? >
>? ? >? ? >? ? I'd say anything between 10 and 20. What you're
looking for
>? ? >? ? is the
>? ? >? ? >? ? effect of the 20 Mhz bandwidth reduction. The
higher the
>? ? >? ? >? ? frequency, the
>? ? >? ? >? ? more obvious.
>? ? >? ? >
>? ? >? ? >? ? Do NOT couple a transmitter directly into the
scope, use
>? ? a dummy
>? ? >? ? >? ? load on
>? ? >? ? >? ? the transmitter, and pick up a signal with a wire loop.
>? ? SA's and
>? ? >? ? >? ? Scopes
>? ? >? ? >? ? cannot tolerate wattage from a transformer. You
could use a
>? ? >? ? 5 Mhz
>? ? >? ? >? ? square wave and look for the edge to see how it
changes,
>? ? that
>? ? >? ? >? ? works, too.
>? ? >? ? >
>? ? >? ? >? ? Harvey
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >? ? On 10/13/2023 11:33 PM, Walt KA2NJF via groups.io
wrote:
>? ? >? ? >? ? > Harvey,
>? ? >? ? >? ? >
>? ? >? ? >? ? > At the present time I have nothing to generate a 20
>? ? MHZ signal
>? ? >? ? >? ? with.
>? ? >? ? >? ? > Will it work with a 20 MHZ RF signal ??
>? ? >? ? >? ? >
>? ? >? ? >? ? > Walt
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? > Sent from the all new AOL app for iOS
>? ? >? ? >? ? >
>? ? >? ? >
>? ? >
>? ?
<>
>? ? >? ? >? ? >
>? ? >? ? >? ? > On Friday, October 13, 2023, 21:45, Harvey White
>? ? >? ? >? ? > <madyn@...> wrote:
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? Take a 20 Mhz square wave and look at it on 20 Mhz
>? ? >? ? bandwidth,
>? ? >? ? >? ? then
>? ? >? ? >? ? >? ? go to
>? ? >? ? >? ? >? ? full bandwidth.? If that doesn't give two
different
>? ? >? ? results, then
>? ? >? ? >? ? >? ? that
>? ? >? ? >? ? >? ? tells you a lot.
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? Harvey
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? >? ? On 10/13/2023 8:07 PM, Walt KA2NJF via
groups.io wrote:
>? ? >? ? >? ? >? ? > Davy,
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? > I have tried recycling all the switches, push
>? ? buttons, and
>? ? >? ? >? ? rotary
>? ? >? ? >? ? >? ? > switches with no change in the Tek 2445
response. I
>? ? >? ? even looked
>? ? >? ? >? ? >? ? for a
>? ? >? ? >? ? >? ? > master reset switch. I have tried recycling
the push
>? ? >? ? buttons,
>? ? >? ? >? ? >? ? switchs
>? ? >? ? >? ? >? ? > and rotary switches on and off for the past
three
>? ? or four
>? ? >? ? >? ? days. The
>? ? >? ? >? ? >? ? > last time I remember it working was a month
or so
>? ? ago.
>? ? >? ? If you
>? ? >? ? >? ? >? ? come up
>? ? >? ? >? ? >? ? > with any more suggestions I am all ears.
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? > Thanks,
>? ? >? ? >? ? >? ? > Walt, KA2NJF
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? > Sent from the all new AOL app for iOS
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >
>? ? >
>? ?
<>
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? > On Friday, October 13, 2023, 17:40, Dave Casey
>? ? >? ? >? ? >? ? <polara413@...>
>? ? >? ? >? ? >? ? > wrote:
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? Walt -
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? Is the 20 Mhz BW Limit pushbutton (located
>? ? directly
>? ? >? ? >? ? above the Ch2
>? ? >? ? >? ? >? ? >? ? Volts/Div knob) depressed? If it is not
depressed,
>? ? >? ? >? ? perhaps the
>? ? >? ? >? ? >? ? >? ? switch has gotten dirty and cycling it a few
>? ? times will
>? ? >? ? >? ? resolve
>? ? >? ? >? ? >? ? >? ? your issue?
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? Dave Casey
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? On Fri, Oct 13, 2023 at 3:25?PM Walt
KA2NJF via
>? ? >? ? groups.io
>? ? >? ? >? ? >? ? >? ? <>
>? ? <wmilton2359@...>
>? ? >? ? >? ? wrote:
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? ? ? Hey,
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? ? ? I just joined the group and my name
is Walter,
>? ? >? ? >? ? KA2NJF I am 80
>? ? >? ? >? ? >? ? >? ? ? ? years old. My Tektronix is in need of
>? ? service. Is
>? ? >? ? >? ? there any
>? ? >? ? >? ? >? ? >? ? ? ? service deposit or any one in the South
>? ? Jersey or
>? ? >? ? >? ? South East
>? ? >? ? >? ? >? ? >? ? ? ? PA who works on this piece of
equipment? I
>? ? can not
>? ? >? ? >? ? get any
>? ? >? ? >? ? >? ? >? ? ? ? frequency reading above 20 MHZ and
this is a
>? ? >? ? 150 MHZ
>? ? >? ? >? ? scope.
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? ? ? Thanks,
>? ? >? ? >? ? >? ? >? ? ? ? Walt, KA2NJF
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >? ? ? ? Sent from the all new AOL app for iOS
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >
>? ? >
>? ?
<>
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>? ? >
>
>
>
>
>
>

---------- Original Message ----------
From: "Harvey White" <madyn@...>
To: [email protected]
Subject: Re: [TekScopes2] Telethons 2445
Date: Sun, 15 Oct 2023 21:04:14 -0400

OK, then that makes all sorts of sense.? With the RF generator, if you
can put out a 10 to 20 Mhz signal, then see what happens with the
bandwidth change.? It ought to go down in amplitude with the bandwidth
limit.

Everything else was on the assumption that you had function generator
that put out square waves.? Many of them do.? Perhaps you're thinking of
an RF signal generator.? Not the same thing.

This was a quick, cobble together test.

Please search the list for specifics on this oscilloscope.? There might
be something specific to your problem.? I'm NOT the expert on these
scopes, and all I can provide are some hints to help in troubleshooting,
and even then, only so much.

Harvey



On 10/15/2023 7:22 PM, Walt KA2NJF via groups.io wrote:
> Harvey,
>
> I don’t have a function generator. My WaveTek function generator does
> Just RF. Also I don’t have a cad program on hand.
>
> I plan on taking the cover off the scope. I can then blow out the dust
> and see if I can apply some Deoxid D5 to the push buttons and switches.
>
> Then I’ll see how high of a signal it will take. I have not seen any
> magic smoke leave the unit so my hopes are high. I will let you know
> how I make out.
>
> Thanks for all your help and assistance !!
>
> Walt
>
>
> Sent from the all new AOL app for iOS
> <https://apps.apple.com/us/app/aol-news-email-weather-video/id646100661>
>
> On Sunday, October 15, 2023, 16:42, Harvey White
> <madyn@...> wrote:
>
> ????I can, but first, you realize that this is nothing more than a
> ????bandwidth
> ????check and a very crude one?? Your function generator ought to go
> ????to to
> ????10 Mhz or so.
>
> ????If it does triangle waves, you can use a triangle instead of a square
> ????(just different harmonics but still needs them).? If the triangle
> ????starts
> ????to round with 20 Mhz bandwidth in, and is reasonably sharp at 20 Mhz
> ????bandwidth out, then you've done the same thing.
>
> ????If the bandwidth is limited, then you'll see that the triangle
> ????looks a
> ????lot like a sine instead of a proper triangle.
>
> ????You don't absolutely need a schmidt trigger, I'm just being a purist.
>
> ????What PC board layout programs do you have?? They have schematic
> ????capture.? Kicad is one.? I personally use an old version of EAGLE,
> ????so I
> ????could deliver this to you as a picture without you having to do
> ????anything.
>
> ????First, though, how high a frequency can your function generator do?
>
> ????Harvey
>
>
> ????On 10/15/2023 3:20 PM, Walt KA2NJF via groups.io wrote:
> ????> Harvey,
> ????>
> ????> Can you draw that up for me. I have to be very careful since my
> ????right
> ????> hand shakes when it wants to. I do have a plug in breadboard that I
> ????> can use. The Schmidt trigger chip I will look a see if I have
> ????any. If
> ????> not then I will purchase some.
> ????>
> ????> Walt
> ????>
> ????>
> ????> Sent from the all new AOL app for iOS
> ????>
> ????<https://apps.apple.com/us/app/aol-news-email-weather-video/id646100661>
> ????>
> ????> On Sunday, October 15, 2023, 12:44, Harvey White
> ????> <madyn@...> wrote:
> ????>
> ????>? ? Can you breadboard TTL?
> ????>
> ????>? ? 1K in series, 5.0 volt P-P sine wave, diodes to VCC and GND
> ????to limit
> ????>? ? what the gate input sees, use any schmidt trigger (74LS14,
> ????etc) to
> ????>? ? produce a pulse output, then run that through a few gates (same
> ????>? ? package)
> ????>? ? to neaten it up, and you have an emergency square wave generator.
> ????>
> ????>? ? Harvey
> ????>
> ????>
> ????>? ? On 10/15/2023 12:19 PM, Walt KA2NJF via groups.io wrote:
> ????>? ? > Harvey,
> ????>? ? >
> ????>? ? > My WaveTek does not support square wave generation.
> ????>? ? >
> ????>? ? > Walt
> ????>? ? >
> ????>? ? >
> ????>? ? > Sent from the all new AOL app for iOS
> ????>? ? >
> ????>? ?
> ????<https://apps.apple.com/us/app/aol-news-email-weather-video/id646100661>
> ????>? ? >
> ????>? ? > On Saturday, October 14, 2023, 13:51, Harvey White
> ????>? ? > <madyn@...> wrote:
> ????>? ? >
> ????>? ? >? ? Ok, how fast is the wavetek signal generator?
> ????>? ? >
> ????>? ? >? ? if it's at least 2 mhz, and can put out a square wave, then
> ????>? ? try that.
> ????>? ? >? ? You're looking for significant edge rounding at any
> ????frequency
> ????>? ? from
> ????>? ? >? ? 2 Mhz
> ????>? ? >? ? on (the higher, the more rounding) in the 20 Mhz position.
> ????>? ? You need
> ????>? ? >? ? about 10x the bandwidth to reproduce a decent square wave.
> ????>? ? i.e. 2 Mhz
> ????>? ? >? ? needs 20 Mhz bandwidth because of the harmonics that
> ????make the
> ????>? ? square
> ????>? ? >? ? wave square.? That's why I suggested something around 10 to
> ????>? ? 20 Mhz.
> ????>? ? >? ? You'd be able to see the effects.? The closer to the 2 Mhz
> ????>? ? you get
> ????>? ? >? ? (and
> ????>? ? >? ? below), the less you'll see the effect of the bandwidth.
> ????>? ? >
> ????>? ? >? ? See if tek WIKI has the service manual.
> ????>? ? >
> ????>? ? >? ? If you can breadboard a TTL oscillator, that might help.
> ????Same
> ????>? ? >? ? restrictions on frequency.
> ????>? ? >
> ????>? ? >? ? Harvey
> ????>? ? >
> ????>? ? >
> ????>? ? >? ? On 10/14/2023 12:02 PM, Walt KA2NJF via groups.io wrote:
> ????>? ? >? ? > Harvey,
> ????>? ? >? ? >
> ????>? ? >? ? > The test equipment I have is:
> ????>? ? >? ? > 1. Wavetek Signal Generator
> ????>? ? >? ? > 2. HP 410C VTVM
> ????>? ? >? ? > 3. Sinometer Frequency Counter
> ????>? ? >? ? > 4. Tel 2445 Scope
> ????>? ? >? ? >
> ????>? ? >? ? > It looks like I will have to purchase some more
> ????equipment if
> ????>? ? >? ? funds let
> ????>? ? >? ? > me !!
> ????>? ? >? ? > I will remove the case and blow out the dust and look at
> ????>? ? the fan. I
> ????>? ? >? ? > will reoil it if possible.
> ????>? ? >? ? > I don’t have a service manual.
> ????>? ? >? ? >
> ????>? ? >? ? > Walt
> ????>? ? >? ? >
> ????>? ? >? ? >
> ????>? ? >? ? > Sent from the all new AOL app for iOS
> ????>? ? >? ? >
> ????>? ? >
> ????>? ?
> ????<https://apps.apple.com/us/app/aol-news-email-weather-video/id646100661>
> ????>? ? >? ? >
> ????>? ? >? ? > On Saturday, October 14, 2023, 00:34, Harvey White
> ????>? ? >? ? > <madyn@...> wrote:
> ????>? ? >? ? >
> ????>? ? >? ? >? ? I'd say anything between 10 and 20. What you're
> ????looking for
> ????>? ? >? ? is the
> ????>? ? >? ? >? ? effect of the 20 Mhz bandwidth reduction. The
> ????higher the
> ????>? ? >? ? >? ? frequency, the
> ????>? ? >? ? >? ? more obvious.
> ????>? ? >? ? >
> ????>? ? >? ? >? ? Do NOT couple a transmitter directly into the
> ????scope, use
> ????>? ? a dummy
> ????>? ? >? ? >? ? load on
> ????>? ? >? ? >? ? the transmitter, and pick up a signal with a wire loop.
> ????>? ? SA's and
> ????>? ? >? ? >? ? Scopes
> ????>? ? >? ? >? ? cannot tolerate wattage from a transformer. You
> ????could use a
> ????>? ? >? ? 5 Mhz
> ????>? ? >? ? >? ? square wave and look for the edge to see how it
> ????changes,
> ????>? ? that
> ????>? ? >? ? >? ? works, too.
> ????>? ? >? ? >
> ????>? ? >? ? >? ? Harvey
> ????>? ? >? ? >
> ????>? ? >? ? >
> ????>? ? >? ? >? ? On 10/13/2023 11:33 PM, Walt KA2NJF via groups.io
> ????wrote:
> ????>? ? >? ? >? ? > Harvey,
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >? ? > At the present time I have nothing to generate a 20
> ????>? ? MHZ signal
> ????>? ? >? ? >? ? with.
> ????>? ? >? ? >? ? > Will it work with a 20 MHZ RF signal ??
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >? ? > Walt
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >? ? > Sent from the all new AOL app for iOS
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >
> ????>? ? >
> ????>? ?
> ????<https://apps.apple.com/us/app/aol-news-email-weather-video/id646100661>
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >? ? > On Friday, October 13, 2023, 21:45, Harvey White
> ????>? ? >? ? >? ? > <madyn@...> wrote:
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? Take a 20 Mhz square wave and look at it on 20 Mhz
> ????>? ? >? ? bandwidth,
> ????>? ? >? ? >? ? then
> ????>? ? >? ? >? ? >? ? go to
> ????>? ? >? ? >? ? >? ? full bandwidth.? If that doesn't give two
> ????different
> ????>? ? >? ? results, then
> ????>? ? >? ? >? ? >? ? that
> ????>? ? >? ? >? ? >? ? tells you a lot.
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? Harvey
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? On 10/13/2023 8:07 PM, Walt KA2NJF via
> ????groups.io wrote:
> ????>? ? >? ? >? ? >? ? > Davy,
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? > I have tried recycling all the switches, push
> ????>? ? buttons, and
> ????>? ? >? ? >? ? rotary
> ????>? ? >? ? >? ? >? ? > switches with no change in the Tek 2445
> ????response. I
> ????>? ? >? ? even looked
> ????>? ? >? ? >? ? >? ? for a
> ????>? ? >? ? >? ? >? ? > master reset switch. I have tried recycling
> ????the push
> ????>? ? >? ? buttons,
> ????>? ? >? ? >? ? >? ? switchs
> ????>? ? >? ? >? ? >? ? > and rotary switches on and off for the past
> ????three
> ????>? ? or four
> ????>? ? >? ? >? ? days. The
> ????>? ? >? ? >? ? >? ? > last time I remember it working was a month
> ????or so
> ????>? ? ago.
> ????>? ? >? ? If you
> ????>? ? >? ? >? ? >? ? come up
> ????>? ? >? ? >? ? >? ? > with any more suggestions I am all ears.
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? > Thanks,
> ????>? ? >? ? >? ? >? ? > Walt, KA2NJF
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? > Sent from the all new AOL app for iOS
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >
> ????>? ? >
> ????>? ?
> ????<https://apps.apple.com/us/app/aol-news-email-weather-video/id646100661>
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? > On Friday, October 13, 2023, 17:40, Dave Casey
> ????>? ? >? ? >? ? >? ? <polara413@...>
> ????>? ? >? ? >? ? >? ? > wrote:
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? >? ? Walt -
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? >? ? Is the 20 Mhz BW Limit pushbutton (located
> ????>? ? directly
> ????>? ? >? ? >? ? above the Ch2
> ????>? ? >? ? >? ? >? ? >? ? Volts/Div knob) depressed? If it is not
> ????depressed,
> ????>? ? >? ? >? ? perhaps the
> ????>? ? >? ? >? ? >? ? >? ? switch has gotten dirty and cycling it a few
> ????>? ? times will
> ????>? ? >? ? >? ? resolve
> ????>? ? >? ? >? ? >? ? >? ? your issue?
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? >? ? Dave Casey
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? >? ? On Fri, Oct 13, 2023 at 3:25?PM Walt
> ????KA2NJF via
> ????>? ? >? ? groups.io
> ????>? ? >? ? >? ? >? ? >? ? <http://groups.io>
> ????>? ? <wmilton2359@...>
> ????>? ? >? ? >? ? wrote:
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? >? ? ? ? Hey,
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? >? ? ? ? I just joined the group and my name
> ????is Walter,
> ????>? ? >? ? >? ? KA2NJF I am 80
> ????>? ? >? ? >? ? >? ? >? ? ? ? years old. My Tektronix is in need of
> ????>? ? service. Is
> ????>? ? >? ? >? ? there any
> ????>? ? >? ? >? ? >? ? >? ? ? ? service deposit or any one in the South
> ????>? ? Jersey or
> ????>? ? >? ? >? ? South East
> ????>? ? >? ? >? ? >? ? >? ? ? ? PA who works on this piece of
> ????equipment? I
> ????>? ? can not
> ????>? ? >? ? >? ? get any
> ????>? ? >? ? >? ? >? ? >? ? ? ? frequency reading above 20 MHZ and
> ????this is a
> ????>? ? >? ? 150 MHZ
> ????>? ? >? ? >? ? scope.
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? >? ? ? ? Thanks,
> ????>? ? >? ? >? ? >? ? >? ? ? ? Walt, KA2NJF
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? >? ? ? ? Sent from the all new AOL app for iOS
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >
> ????>? ? >
> ????>? ?
> ????<https://apps.apple.com/us/app/aol-news-email-weather-video/id646100661>
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >? ? >
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >? ? >
> ????>? ? >? ? >
> ????>? ? >? ? >
> ????>? ? >? ? >
> ????>? ? >? ? >
> ????>? ? >? ? >
> ????>? ? >? ? >
> ????>? ? >
> ????>? ? >
> ????>? ? >
> ????>? ? >
> ????>? ? >
> ????>? ? >
> ????>
> ????>
> ????>
> ????>
> ????>
> ????>
>
>
>
>
>
>

-----Original Message-----
From: [email protected] <[email protected]> On Behalf Of Tom Gardner
Sent: 16 October 2023 08:11
To: [email protected]
Subject: Re: [TekScopes2] Telethons 2445

On Sunday, October 15, 2023, 16:42, Harvey White
<madyn@...>
wrote:

I can, but first, you realize that this is nothing more than a
bandwidth check and a very crude one? Your function generator ought
to go to to
10 Mhz or so.

To get philosophical for a moment, a scope is a V-vs-t instrument, so the fidelity of the time domain response is paramount. As such, frequency domain measurements are merely an indirect analogue of what's important.

Hence observing a scope's step response is, IMNSHO, the best technique.
Hence, IMNSHO, characterising a scope's performance by bandwidth is wrongheaded :)

Curiously my latest scope, a Philips PM3410, got that right. The spec printed on the front panel is 200ps, and 1.7GHz is only mentioned deep in the manual. The PM3410 is a fun device: the transistors in the signal chain are mostly BC107s with an fT of 0.2GHz. There are three 2GHz FETs in the trigger.

Alternatively, iIf frequency domain response is paramount, use a V-vs-f instrument, i.e. a spectrum analyser. (And never forget the third of the triumvirate, f-vs-t, i.e. the modulation domain :) )