Re: 2247A Channel 1 issue
I just checked R101 and R102 on a bare 2246 mainboard and they
both measured 8.2k ohms in circuit.
If the resistance is correct on your scope, then something is
drawing enough current to drop 0.7 volts across R101.
Nothing in that simple circuit looks like a suspect to me, no
nasty 10uF to 47uF tantalums, etc.
tom jobe...
?
?
?
toggle quoted message
Show quoted text
----- Original Message -----
Sent: Thursday, September 20, 2012 1:20
PM
Subject: [TekScopes] Re: 2247A Channel 1
issue
?
Thanks again for the responce. I think we are getting
there.
Using cahannel 2 as the "working reference"
pin 12
(channel 2) on u506 goes from the +2.5 to +1.4 when a 10x probe is
connected.
pin (15 channel 1) on U506 goes from +.9 to +.6 with the
probe connected.
Checking R102 for channel 2 it has +2.5
R101,
(channel 1), shows +2.5 in but only +1.8 out.
What are your thoughts?
Is it simply a bad resistor or would one of the cap, C111 cause the voltage
drop?
Thanks again, KT
--- In TekScopes@..., "Tom
Jobe" wrote:
>
> For the record, I slid the
cover back on a very dead 2246 and checked pin 12 and pin 15 of U506, they
both had +2.49 volts with no probes attached.
> This scope does not have
any lights on the front, and none of the buttons work, so I could not see the
reading I would get at ground, or with a 1X or a 10X probe.
> tom
jobe...
>
>
>
>
>
> ----- Original
Message -----
> From: lldskjfoi
> To: TekScopes@...
> Sent: Thursday, September 20, 2012 8:28 AM
> Subject:
[TekScopes] Re: 2247A Channel 1 issue
>
>
>
>
Thanks, thanks the info I was looking for. I started getting into the
schematic last night I saw the path to U506. Will start checking it
out.
>
> Also notice just letting the scope run with the probe
attached the attenuation factor jumps back and forth- correct / incorrect.
Does not change with no probe attached so it is getting an intermitant
signal.
>
> KT
>
> --- In TekScopes@..., "Tom
Jobe" wrote:
> >
> > Maybe start by looking
at the #1 "Vertical Inputs" schematic to see the simple circuit which starts
at the junction of R101, C101 and R105 for channel 1.
> > That
junction point is connected to the readout ring behind the BNC connector, so
you could test for continuity and shorting to ground, etc.
> > If you
compared both ends of R101 and R105 (Chan 1) with those of R102 and R106 (Chan
2) you might see if the readout voltage is getting that far.
> > If
that looked okay, you could go to U506 and see if it arrives at pins 12 and 15
as you would expect.
> > With the scope on its back, you have
excellent access to all of these resistors and U506 (16 pin DIP), with the
blue outer cover slid back the width of your hand.
> > From reading
the service manual, it appears that the readout signal gets changed to a
digital signal at U506, but is a simple voltage up to U506.
> > tom
jobe...
> >
> >
> >
> >
> >
----- Original Message -----
> > From: lldskjfoi
> > To:
TekScopes@...
> > Sent: Wednesday, September 19, 2012 9:08 PM
> >
Subject: [TekScopes] Re: 2247A Channel 1 issue
> >
> >
> >
> > Some more checking shows channel 1 is not getting
the code signal from the probe. Any idea on this circuit?
> >
> > KT
> >
> > --- In TekScopes@...,
"lldskjfoi" wrote:
> > >
> > >
Hello everyone.
> > >
> > > Initial test show an
issue with channel 1.
> > >
> > > Any direction on
where to start?
> > >
> > > Channel 2 displays inputs
correctly from the FG.
> > >
> > > Channel 1 displays
10 times the amplitude for the same signal.
> > >
> >
> Example a 1 volt sine wave on channel 2 displays on the voltmeter
function correctly at ~1v and 2 divisions at .5v / div.
> > >
> > > The same signal on channel one reads as ~10v. When set to
5v / div it fills two div.
> > >
> > > Thanks,
KT
> > >
> >
>
|
Re: tektronix 177 test fixture pin spacing
?
Thanks Dennis,
That was a great laser printing tip!
tom jobe...
?
?
----- Original Message -----
Sent: Thursday, September 20, 2012 1:41
PM
Subject: RE: [TekScopes] tektronix 177
test fixture pin spacing
?
WATCH OUT FOR
PAPER SHRINKAGE ON A LASERJET PRINTER! This can drive you nuts until you
realize what is happening.
The heat from a
Laserjet fuser roller causes the paper to shrink 2% to 3% as it is being
printed. This is due to the moisture content of the paper which the fuser
bakes out of the paper. To get truly accurate drawings from a laser printer
you have to pass the sheet of paper through the fuser 2 times before printing
your drawing on it.
To do this I use
any word processor to print a blank sheet of paper. Then I reinsert the sheet
into the manual paper tray and print a blank page on it a second time. After
passing through the fuser two times the sheet won¡¯t shrink
anymore.
Then, and only
then you can feed it into the manual tray and print your drawing on it. Now it
will be dimensionally accurate.
InkJet printers
do not have this problem. A drawing prints out perfectly each time on an
inkjet.
Dennis
From: Glydeck, Sent: Tuesday, September 18, 2012
1:41 PM
Gang,
I¡¯ve taken Tom¡¯s dimensions and converted them
to a scale PDF. ?I then printed the 1:1 drawing on a laser printer, cut
it out, and dropped it on top of a 177 test fixture to test the accuracy of
the drawing. ?Using two consecutive images as different Photoshop layers
I was able to set the opacity of the paper cut out to see how it compares to
the actual location of the holes on the test fixture. ?I uploaded a
series of pictures to TekScopes.
?
<>?
?
The
full scale PDF was uploaded to TekScopeArc2. ?If you print it out be sure
to set ¡®Scale¡¯ to none.
?
?
George
On Sep 18, 2012, at 8:16 AM, Glydeck <glydeck@...> wrote:
?
Perfect! Just what is needed. I'll share a full scale PDF
later today.
Better living through chemistry? ;-)
Mark
On 09/17/2012
08:45 PM, Rob wrote:
>
>
> Dang Tom, you do better
freehand then I can in AutoCAD¡. good thing I
> remain in
chemicals...
>
> *From:* TekScopes@...
[mailto:TekScopes@...]
> *On Behalf Of *Tom Jobe
> *Sent:* Monday, September 17,
2012 6:21 PM
> *To:* TekScopes@...
>
*Subject:* Re: [TekScopes] tektronix 177 test fixture pin spacing [1
> Attachment]
>
> *[Attachment(s) <#TopText> from
Tom Jobe included below]*
>
>
> George,
>
>
In case my explanation didn't make sense, here is a quick sketch of
> the dimensions of the 577/177 test fixture
layout.
>
> Everything is in inches.
>
> tom
|
Re: San Diego 7934 and goodies
The 7934 is an uncommon scope because it came out late in the 7000 lifecycle
(1987) For some odd reason it was not listed in the 1988 catalog but it
reappeared in the 1989 and 1990 catalogs. In most respects it is a higher
bandwidth 7834 which was discontinued after 1985.
The 7834 was a 400 MHz scope but the 7934 is the fastest storage scope Tek
made at 500MHz.
Dennis
toggle quoted message
Show quoted text
-----Original Message----- From: Stefan Trethan, Sent: Wednesday, September 19, 2012 11:58 AM Does a vertical amp anything useful together with a 7D20 in a 4-bay mainframe? Not that the 7D20 in a 7934 makes all that much sense to start with..... Looks like a bit of a mix, but should be a good deal if you can use only some of the items. I really wonder if the curve tracer those fixtures go with is anywhere nearby. The current probe(s) would also be interesting. ST On Wed, Sep 19, 2012 at 8:09 PM, sipespresso <sipespresso@...> wrote: I have no affiliation with the seller. I emailed them an confirmed that they are asking for $160.
-Kurt
|
Re: tektronix 177 test fixture pin spacing
WATCH OUT FOR PAPER SHRINKAGE ON A LASERJET PRINTER! This can drive you nuts until you realize what is happening. ? The heat from a Laserjet fuser roller causes the paper to shrink 2% to 3% as it is being printed. This is due to the moisture content of the paper which the fuser bakes out of the paper. To get truly accurate drawings from a laser printer you have to pass the sheet of paper through the fuser 2 times before printing your drawing on it. ? To do this I use any word processor to print a blank sheet of paper. Then I reinsert the sheet into the manual paper tray and print a blank page on it a second time. After passing through the fuser two times the sheet won¡¯t shrink anymore. ? Then, and only then you can feed it into the manual tray and print your drawing on it. Now it will be dimensionally accurate. ? InkJet printers do not have this problem. A drawing prints out perfectly each time on an inkjet. ? Dennis ? From: Glydeck, Sent: Tuesday, September 18, 2012 1:41 PM
Gang,
I¡¯ve taken Tom¡¯s dimensions and converted them to a scale PDF. ?I then printed the 1:1 drawing on a laser printer, cut it out, and dropped it on top of a 177 test fixture to test the accuracy of the drawing. ?Using two consecutive images as different Photoshop layers I was able to set the opacity of the paper cut out to see how it compares to the actual location of the holes on the test fixture. ?I uploaded a series of pictures to TekScopes.
?
<>?
?
The full scale PDF was uploaded to TekScopeArc2. ?If you print it out be sure to set ¡®Scale¡¯ to none.
?
?
George
On Sep 18, 2012, at 8:16 AM, Glydeck <glydeck@...> wrote:
? Perfect! Just what is needed. I'll share a full scale PDF later today. Better living through chemistry? ;-)
Mark
On 09/17/2012 08:45 PM, Rob wrote:
>
>
> Dang Tom, you do better freehand then I can in AutoCAD¡. good thing I
> remain in chemicals...
>
> *From:* TekScopes@... [mailto:TekScopes@...]
> *On Behalf Of *Tom Jobe
> *Sent:* Monday, September 17, 2012 6:21 PM
> *To:* TekScopes@...
> *Subject:* Re: [TekScopes] tektronix 177 test fixture pin spacing [1
> Attachment]
>
> *[Attachment(s) <#TopText> from Tom Jobe included below]*
>
>
> George,
>
> In case my explanation didn't make sense, here is a quick sketch of
> the dimensions of the 577/177 test fixture layout.
>
> Everything is in inches.
>
> tom
|
Re: 2247A Channel 1 issue
Thanks again for the responce. I think we are getting there.
Using cahannel 2 as the "working reference"
pin 12 (channel 2) on u506 goes from the +2.5 to +1.4 when a 10x probe is connected.
pin (15 channel 1) on U506 goes from +.9 to +.6 with the probe connected.
Checking R102 for channel 2 it has +2.5
R101, (channel 1), shows +2.5 in but only +1.8 out.
What are your thoughts? Is it simply a bad resistor or would one of the cap, C111 cause the voltage drop?
Thanks again, KT
toggle quoted message
Show quoted text
--- In TekScopes@..., "Tom Jobe" <tomjobe@...> wrote:
For the record, I slid the cover back on a very dead 2246 and checked pin 12 and pin 15 of U506, they both had +2.49 volts with no probes attached.
This scope does not have any lights on the front, and none of the buttons work, so I could not see the reading I would get at ground, or with a 1X or a 10X probe.
tom jobe...
----- Original Message -----
From: lldskjfoi
To: TekScopes@...
Sent: Thursday, September 20, 2012 8:28 AM
Subject: [TekScopes] Re: 2247A Channel 1 issue
Thanks, thanks the info I was looking for. I started getting into the schematic last night I saw the path to U506. Will start checking it out.
Also notice just letting the scope run with the probe attached the attenuation factor jumps back and forth- correct / incorrect. Does not change with no probe attached so it is getting an intermitant signal.
KT
--- In TekScopes@..., "Tom Jobe" <tomjobe@> wrote:
>
> Maybe start by looking at the #1 "Vertical Inputs" schematic to see the simple circuit which starts at the junction of R101, C101 and R105 for channel 1.
> That junction point is connected to the readout ring behind the BNC connector, so you could test for continuity and shorting to ground, etc.
> If you compared both ends of R101 and R105 (Chan 1) with those of R102 and R106 (Chan 2) you might see if the readout voltage is getting that far.
> If that looked okay, you could go to U506 and see if it arrives at pins 12 and 15 as you would expect.
> With the scope on its back, you have excellent access to all of these resistors and U506 (16 pin DIP), with the blue outer cover slid back the width of your hand.
> From reading the service manual, it appears that the readout signal gets changed to a digital signal at U506, but is a simple voltage up to U506.
> tom jobe...
>
>
>
>
> ----- Original Message -----
> From: lldskjfoi
> To: TekScopes@...
> Sent: Wednesday, September 19, 2012 9:08 PM
> Subject: [TekScopes] Re: 2247A Channel 1 issue
>
>
>
> Some more checking shows channel 1 is not getting the code signal from the probe. Any idea on this circuit?
>
> KT
>
> --- In TekScopes@..., "lldskjfoi" <k.templin@> wrote:
> >
> > Hello everyone.
> >
> > Initial test show an issue with channel 1.
> >
> > Any direction on where to start?
> >
> > Channel 2 displays inputs correctly from the FG.
> >
> > Channel 1 displays 10 times the amplitude for the same signal.
> >
> > Example a 1 volt sine wave on channel 2 displays on the voltmeter function correctly at ~1v and 2 divisions at .5v / div.
> >
> > The same signal on channel one reads as ~10v. When set to 5v / div it fills two div.
> >
> > Thanks, KT
> >
>
|
Re: 2247A Channel 1 issue
For the record, I slid the cover back on a very dead 2246 and
checked pin 12 and pin 15 of U506, they both had +2.49 volts with no probes
attached.
This scope does not have any lights on the front, and none of
the buttons work, so I could not see?the reading I would get at ground, or
with a 1X or?a 10X probe.
tom jobe...
?
?
?
?
?
toggle quoted message
Show quoted text
----- Original Message -----
Sent: Thursday, September 20, 2012 8:28
AM
Subject: [TekScopes] Re: 2247A Channel 1
issue
?
Thanks, thanks the info I was looking for. I started getting into the
schematic last night I saw the path to U506. Will start checking it
out.
Also notice just letting the scope run with the probe attached the
attenuation factor jumps back and forth- correct / incorrect. Does not change
with no probe attached so it is getting an intermitant
signal.
KT
--- In TekScopes@..., "Tom
Jobe" wrote:
>
> Maybe start by looking at the
#1 "Vertical Inputs" schematic to see the simple circuit which starts at the
junction of R101, C101 and R105 for channel 1.
> That junction point is
connected to the readout ring behind the BNC connector, so you could test for
continuity and shorting to ground, etc.
> If you compared both ends of
R101 and R105 (Chan 1) with those of R102 and R106 (Chan 2) you might see if
the readout voltage is getting that far.
> If that looked okay, you
could go to U506 and see if it arrives at pins 12 and 15 as you would
expect.
> With the scope on its back, you have excellent access to all
of these resistors and U506 (16 pin DIP), with the blue outer cover slid back
the width of your hand.
> From reading the service manual, it appears
that the readout signal gets changed to a digital signal at U506, but is a
simple voltage up to U506.
> tom jobe...
>
>
>
>
> ----- Original Message -----
> From: lldskjfoi
> To: TekScopes@...
> Sent: Wednesday, September 19, 2012 9:08 PM
> Subject:
[TekScopes] Re: 2247A Channel 1 issue
>
>
>
> Some
more checking shows channel 1 is not getting the code signal from the probe.
Any idea on this circuit?
>
> KT
>
> --- In TekScopes@...,
"lldskjfoi" wrote:
> >
> > Hello
everyone.
> >
> > Initial test show an issue with channel
1.
> >
> > Any direction on where to start?
> >
> > Channel 2 displays inputs correctly from the FG.
> >
> > Channel 1 displays 10 times the amplitude for the same
signal.
> >
> > Example a 1 volt sine wave on channel 2
displays on the voltmeter function correctly at ~1v and 2 divisions at .5v /
div.
> >
> > The same signal on channel one reads as ~10v.
When set to 5v / div it fills two div.
> >
> > Thanks,
KT
> >
>
|
I2C / SPI Bus Analysis with TDS754C?
Does anyone know if there is a software product that works with a TDS scope for digital bus analysis? I know you can purchase little boxes that do this, but I wanted to make sure before I buy yet another gadget.
Thanks
|
Re: HP Agilent YIG 5086-7096 Mixer 5086-7059
Because of the overtly stated issue of how you bypassed import/export regulations --
WHAT COUNTRY ARE YOU IN?
This is an important question, because if we provide any information or
assistance, it may constitute a crime on our respective homelands. ?In fact, our mere knowledge that you smuggled out what may be a controlled technology may constitute a crime if we don't report it ... at least for Americans, where this particular instance ?technology smuggling apparently began.
73 Jim N6OTQ
From: Asadullah
To: TekScopes@...
Sent: Thursday, September 20, 2012 1:55 AM
Subject: [TekScopes] HP Agilent YIG 5086-7096 Mixer 5086-7059
Hi everybody, A group of my students who
are working on a broa band swept oscillator purchased a YIG oscillator on my advice. (Ebay) I am unable to find the pinout of the YIG. It cannot be used. The unit is cosmetically sound and probably ( I hope) working Its part number is 5086-7096.? When purchased, it came attached by a hard coax to, what is stated on the label, to be a mixer with part number 5086-7059. All my search has to date yeilded no result. Could somebody help, please. This is really important as the students have no access to any option. They cannot import something else as I collected it from the USA myself, by passing import regulations etc. I will be extremely thankful for any information leading to its successful use. Also the mixer assembly which is probably useful too. Thank you for the help. Azzy ------------------------------------ Yahoo! Groups Links <*> To visit your group on the web, go
to: ? ? <*> Your email settings: ? ? Individual Email | Traditional <*> To change settings online go to: ? ? ? ? (Yahoo! ID required) <*> To change settings via email: ? ? TekScopes-digest@... ? ? TekScopes-fullfeatured@...<*> To unsubscribe from this group, send an email to: ? ? TekScopes-unsubscribe@...<*> Your use of Yahoo! Groups is subject to: ? ?
|
Re: 2247A Channel 1 issue
Thanks, thanks the info I was looking for. I started getting into the schematic last night I saw the path to U506. Will start checking it out.
Also notice just letting the scope run with the probe attached the attenuation factor jumps back and forth- correct / incorrect. Does not change with no probe attached so it is getting an intermitant signal.
KT
toggle quoted message
Show quoted text
--- In TekScopes@..., "Tom Jobe" <tomjobe@...> wrote:
Maybe start by looking at the #1 "Vertical Inputs" schematic to see the simple circuit which starts at the junction of R101, C101 and R105 for channel 1.
That junction point is connected to the readout ring behind the BNC connector, so you could test for continuity and shorting to ground, etc.
If you compared both ends of R101 and R105 (Chan 1) with those of R102 and R106 (Chan 2) you might see if the readout voltage is getting that far.
If that looked okay, you could go to U506 and see if it arrives at pins 12 and 15 as you would expect.
With the scope on its back, you have excellent access to all of these resistors and U506 (16 pin DIP), with the blue outer cover slid back the width of your hand.
From reading the service manual, it appears that the readout signal gets changed to a digital signal at U506, but is a simple voltage up to U506.
tom jobe...
----- Original Message -----
From: lldskjfoi
To: TekScopes@...
Sent: Wednesday, September 19, 2012 9:08 PM
Subject: [TekScopes] Re: 2247A Channel 1 issue
Some more checking shows channel 1 is not getting the code signal from the probe. Any idea on this circuit?
KT
--- In TekScopes@..., "lldskjfoi" <k.templin@> wrote:
>
> Hello everyone.
>
> Initial test show an issue with channel 1.
>
> Any direction on where to start?
>
> Channel 2 displays inputs correctly from the FG.
>
> Channel 1 displays 10 times the amplitude for the same signal.
>
> Example a 1 volt sine wave on channel 2 displays on the voltmeter function correctly at ~1v and 2 divisions at .5v / div.
>
> The same signal on channel one reads as ~10v. When set to 5v / div it fills two div.
>
> Thanks, KT
>
|
Re: 2247A Channel 1 issue
Maybe start by looking at the #1 "Vertical Inputs" schematic
to see the simple circuit which starts at the junction of R101, C101 and
R105?for channel 1.
That junction point is connected to the readout ring behind
the BNC connector, so you could test for continuity and shorting to ground,
etc.
If you compared both ends of? R101 and R105 (Chan
1)?with those of R102 and R106 (Chan 2) you might see if the readout
voltage is getting that far.
If that looked okay, you could go to U506 and see if it
arrives at pins 12 and 15 as you would expect.
With the scope on its back, you have excellent access to all
of these resistors and U506 (16 pin DIP), with the blue outer cover?slid
back the width of your hand.
From reading the service manual, it appears that the readout
signal gets changed to a digital signal at U506, but is a simple voltage up to
U506.
tom jobe...
?
?
?
?
toggle quoted message
Show quoted text
----- Original Message -----
Sent: Wednesday, September 19, 2012 9:08
PM
Subject: [TekScopes] Re: 2247A Channel 1
issue
?
Some more checking shows channel 1 is not getting the code signal from the
probe. Any idea on this circuit?
KT
--- In TekScopes@...,
"lldskjfoi" wrote:
>
> Hello
everyone.
>
> Initial test show an issue with channel 1.
>
> Any direction on where to start?
>
> Channel 2 displays
inputs correctly from the FG.
>
> Channel 1 displays 10 times the
amplitude for the same signal.
>
> Example a 1 volt sine wave on
channel 2 displays on the voltmeter function correctly at ~1v and 2 divisions
at .5v / div.
>
> The same signal on channel one reads as ~10v.
When set to 5v / div it fills two div.
>
> Thanks,
KT
>
|
Tektronix parts and the 1410 Generator
Hi.
I have a working 1410 video signal generator, but I am thinking of scrapping it. I've pulled a few boards and of course it is loaded with great parts. I have not found any manual for this device, but I suppose there are a bunch of general purpose circuits in it.
I just got into the multiburst board and there is fancy looking socketed package
"TEK 155 0195 00"
Is this part of interest to anyone? I've searched the net for it and just three sites list it, one as a hybrid shaper circuit.
Studying this multiburst board makes me want to understand this instrument. Unfortunately there is no free documentation available. Any help or advice greatly appreciated. This one was made in 1985 and has all bays filled.
- Tim
|
Re: 2247A Channel 1 issue
Hi,
you should check, that there is no short on the "sensor" ring of the
input which shows
the 10X signal. Normally the sensor, when open tells 1:1 probe and
for probes
with 10:1 a.s.o. it is conncted via a resistor to ground !!!
Herbert
Am 20-09-2012 14:54, schrieb lldskjfoi:
toggle quoted message
Show quoted text
?
They on 10x non swtichable.
KT
--- In TekScopes@...,
Pat-W9ZO wrote:
>
>
> I know it is probably silly to ask, but are you sure
that the switch on
> one probe isn't set for the x10 setting ?
> PatM
>
============================================================
> lldskjfoi wrote the following on 9/19/2012 9:59 PM:
> >
> > Hello everyone.
> >
> > Initial test show an issue with channel 1.
> >
> > Any direction on where to start?
> >
> > Channel 2 displays inputs correctly from the FG.
> >
> > Channel 1 displays 10 times the amplitude for
the same signal.
> >
> > Example a 1 volt sine wave on channel 2 displays
on the voltmeter
> > function correctly at ~1v and 2 divisions at .5v
/ div.
> >
> > The same signal on channel one reads as ~10v.
When set to 5v / div it
> > fills two div.
> >
> > Thanks, KT
> >
> >
> .
>
|
Re: 2247A Channel 1 issue
They on 10x non swtichable.
KT
toggle quoted message
Show quoted text
--- In TekScopes@..., Pat-W9ZO <malfam2@...> wrote:
I know it is probably silly to ask, but are you sure that the switch on
one probe isn't set for the x10 setting ?
PatM
============================================================
lldskjfoi wrote the following on 9/19/2012 9:59 PM:
Hello everyone.
Initial test show an issue with channel 1.
Any direction on where to start?
Channel 2 displays inputs correctly from the FG.
Channel 1 displays 10 times the amplitude for the same signal.
Example a 1 volt sine wave on channel 2 displays on the voltmeter
function correctly at ~1v and 2 divisions at .5v / div.
The same signal on channel one reads as ~10v. When set to 5v / div it
fills two div.
Thanks, KT
.
|
Which Torx Size must I buy to refurberish someTM5000 Series Relais
Hi to All,
Which Torx Size must I buy to put into the very very small Torx Screws, used for the fixation of the 148-0128-03 Relais in e.g. a FG5010? Thank you in advance.
Greetings,
Egge Siert
|
Re: 2247A Channel 1 issue
I know it is probably silly to ask, but are you sure that the
switch on one probe isn't set for the? x10 setting ?
PatM
============================================================
lldskjfoi wrote the following on 9/19/2012 9:59 PM:
?
Hello everyone.
Initial test show an issue with channel 1.
Any direction on where to start?
Channel 2 displays inputs correctly from the FG.
Channel 1 displays 10 times the amplitude for the same
signal.
Example a 1 volt sine wave on channel 2 displays on the
voltmeter function correctly at ~1v and 2 divisions at .5v
/ div.
The same signal on channel one reads as ~10v. When set to
5v / div it fills two div.
Thanks, KT
.
|
Re: New to group - Just acquired a R7844
The funny part of the story is the pawn shop owner said he fired the employee who took the scope in for pawn when the owner did not come back to pay off the pawn and pick it up. He was convinced that he could never sell it and that was why it was not on the sales floor.
I guess its better to be lucky than good as they say! I have figured out how to use now and I love it.
toggle quoted message
Show quoted text
--- In TekScopes@..., "k4mt" <k4mt@...> wrote:
Hi All:
I just found a working R7844 with 7A26, 7A24, and two 7B85 plugins. I was in a pawn shop and saw it on a shelf in the back room. I asked the owner and he said it had been sitting there for 5 years and he did not know what it was. He brought it down and I powered it up. Nice bright traces and ran a wire to calibrator output and all channels worked.
The best news is he wanted it off his shelf and asked me for an offer. Just for laughs I offered him $40.00 and he couldn't say yes quick enough. (guess I should have offered $20.00).
I have used scopes my whole life but not one like this. Am still trying to learn how to use it as I have no users manual. Was able to use it this weekend to troubleshoot my Ham radio PLL with a 60 Mhz output that my old scope could hardly see. What a great piece of test gear!
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TEK 1401A Spectrum Analyzer
Hi Everybody!
I recently bought a tek 1401A from Ebay (sans the tiny scope that goes with it. Alas.). It lacks the battery/charger module but otherwise seems to be complete except for a missing fine frequency pot and multiturn knob.
It seems to have been much molested. I have already seen some transistors which have been stuck in the wrong way around. The power supply is dead but I managed to fix it. (Dead main chopper transistor, shorted 6.4 V zener shorted 22u cap in the +10V section )
If anyone has the same S/A and is working on it (or not|) I would like to join up with him and share my experience of the repair job.
I have collection of old Tek stuff and want to restore it to as close to original as posible.
Azzy
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HP Agilent YIG 5086-7096 Mixer 5086-7059
Hi everybody,
A group of my students who are working on a broa band swept oscillator purchased a YIG oscillator on my advice. (Ebay)
I am unable to find the pinout of the YIG. It cannot be used. The unit is cosmetically sound and probably ( I hope) working
Its part number is 5086-7096. When purchased, it came attached by a hard coax to, what is stated on the label, to be a mixer with part number 5086-7059.
All my search has to date yeilded no result. Could somebody help, please.
This is really important as the students have no access to any option. They cannot import something else as I collected it from the USA myself, by passing import regulations etc.
I will be extremely thankful for any information leading to its successful use. Also the mixer assembly which is probably useful too.
Thank you for the help.
Azzy
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504, RM504, and other stuff in Boston
I have no affiliation with the seller.
-Kurt
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correcting 5v supply on a 5110
I have this lovely collection of broken scopes. On one the 5v supply is off. If I understand the regulator circuits correctly this voltage is referenced to the other voltages, which are correct.
If the 5v is off (4.8v) should I be looking for shorted caps, drifted resistors and failed semis around the 5v regulator or is there some obvious thing I'm missing?
thanks again,
Jamie
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Patrick