开云体育

On Sunday, October 15, 2023, 21:04, Harvey White <madyn@...> wrote:

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
> <>
>
> 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 Monday, October 16, 2023, 11:06, Dave_G0WBX via groups.io <g8kbvdave@...> wrote:

You can of course, still use a SIne wave signal, set for (say) 40 or 50MHz.

(A 20MHz BandWidth limit should noticeably reduce it's amplitude,

compared to "Full" bandwidth mode.)

By comparison, a signal of (say) 10MHz Sine, should hardly change at all

when the BW Limit is used.

If both frequencies, do not show a change in level, when you toggle the

BW Limit, then the 'scope is stuck in one or the other mode..

I can do a similar check here and send pictures if needed.

Regards.

Dave B

(Ex Tektronix UK, back in the day.)

--

Created on and sent from a Unix like PC running and using free and open source software: