开云体育

Hi Everyone,

I am in the process of reverse engineering 2 PCB:-

1, the 278x processor Serial IO PCB
2, an extension card
3, look at the s/w Bob has provided, can it be used under DOS. Lotus 123 and Lotus measure with 2 x GPIB control will be a challenge.

Bob Koller was generous enough and provide me on loan several PCB to reverse engineer.

I am starting another directory (2782 HW & SW service info) and this will contain all relevant data, schematics etc that I work through to resolve an issue with a 2782.

I would also like to reach out to anyone who may have any additional schematics or any information on the 2782/2784. I have a unit with late revision PCB, some schematics do not appear to match. For example the A29 PCB 100MHz) ref source PCB in my unit it is a 670-9461-07. The bottom side of the PCB has an alternative schematic (no ECL).


Regards
Gerald
VK3GM

Hello Dave,

I would try to allign all the 3 filters in the VR unit (Variable Resolution Module). After so many years the trimmer contact (internal) might have worsen a bit and one or more filters might not have the right shape or the amplitude might be too low. So it perhaps helps to exercise these trimmers one by one while looking at the filter shape using the calibrator signal. Please take note that the calibrator signal can be not exactly 100MHz. In the VR unit there are the 300kHz, 30kHz and the 3kHz filters. Unscrew the VR unit and try to flip it so the bottom side comes into view. Have a look at the Service Manual about this too.
The 300 Hz filter is on a smaller seperate board. The trimmers for this one are hard to reach. You need an extension board for this one. I would skip this one for the time being.

Hope to hear from you.

Jaap PA0JRK

Mine uses .050 allen screw (hex).

Bob.

Also yes, they appear to be 0.050 inch. I'll check when I get home.

Ben

No, these are smaller than that. The time base knob uses 1/16 inch. This one doesn't.

Those are typically 1/16" (0.0625") hex drive (aka Allen drive). Some are 0.050" hex drive but they're not quite as common (and it looks like the ones you're showing are 0.0625").

Barry - N4BUQ

Hi,

I have a Tektronix 314 that utilizes these tiny grey knobs for the x10 sweep mag. I want to remove this knob so I can give this scope a proper clean. My issue is I'm having a hard time finding a good tool to remove the grub screw. I've been using a torx bit, but I've noticed that it it damaged the keying over time. So I wanted to ask here what the actual key shape, type, and size is.
Photos:
/g/TekScopes/album?id=295121

Thanks,

Benjamin

Which specific model 7912?

Correction :

Where is circuit that deals with Linear BW Filtering Normalization located in the 2712? Also, how is it different from the Log BW filtering normalization circuit?

hi,

To clarify:

Looking for the Saugamo * Printed #'s / Letters * Identification sheets for these Rectangular Red "potted" or dipped Caps !
( Not their paper nor metal can Caps ; -- Nor the ones with the Colored Dots identifications on them ! )

& any Specification data sheets Or Catalogs

So, for example:
The only ID printed on these Saugamo Caps are printed in Black ink:
e.g. " CM158300J " printed in Black ink, on the red 'rubber' packaging.
this particular axial Cap is ~ 1/4" x 1/2" x 3/16" in size.

thanks !

Where is circuit that deals with Linear BW Filtering Normalization located in the 7912?

SMB would be better - more compact out front especially - but the mounting hole is typically around 3/16" D I think, while the BSM and SMA holes are around 1/4", so an easier direct drop-in fit. SMB would work if you can find some with 1/4" D shanks, or have some kind of bushings or such to adapt to the hole, but then the shank length has to be enough to handle the extra hardware thickness.

Ed

Ed-
I like that idea....I have MB stuff, but......the sma or even smb is a whole lot better......it is now on my to do list.
搁别苍é别

Years ago I started changing any and all BSM connectors I encountered (mostly on Tek S-5X sampling head family) to SMA, so future compatibility is good. I think there may be a couple of heads and other items still needing the changeover when I eventually fool around with them again, but they will definitely be done at some point. It's very easy to do if you have the right parts on hand, and you'll never have to look back (except for talking about it, like now).

Ed

I'm baaack - I think. Spent a lot of time and grief trying switch my whole list of groups in .io, with bad results. I gave up on trying any more with the old PC WinXP, but I couldn't figure out how to force the login changes and such to match the setup of my newer Win10/11 PC. Because of all this crap, it looks like I'll have to rejoin every group separately.

I already had another groups.io account using my main email a while ago, and had used it to join a few groups more recently. The bulk of the long-term groups were registered with my ancient yahoo mail account, which is a PITA to use. These were mostly from way back to the move from yahoogroups (remember that?). It was nice because I could see the whole list of groups in the main window, then pick what to look at. I only want to view from the main portal website, and no email.

Anyway, I had my other account so buggered up that I could not see the main list anymore, and further attempts to change the settings got me to some ostracized state called "bounce" email, and when I clicked the button to send an email to re-verify or whatever, it did nothing a couple dozen times in a row. So, I can't even undo whatever I did to break it. I also can't remember the account setup for the old yahoo, so have to re-figure that out to make it work somewhat for other old things that I still need. So much for that.

Tekscopes was easy to remember and look up, so this is my first try to rejoin with hopefully the new setup. If this works, then I'll do the rest, but I don't think I'll be able to remember the exact names of some, so will be asking for help to re-ID certain ones that other group members likely are in also.

So, here goes. It looks pretty good so far - tekscopes now shows up in the same list as the ones joined more recently. So, I'll just have to recall and find all the others. I tried the search function, but it doesn't seem to work very well.

Ed

Hi,

When I bought a 067-0587-01 Calibration Fixture I thought to replace the BM socket at the trigger out with a mini BNC but fortunately I located some NOS in sealed bags that where pristine. The manufacturer was Automatic metal products corp. The markings are 94375? RF 0721? 1 1. At a first glace they look like Mini BNC but the pin gender is reversed.

A picture is here:

/g/TekScopes/photo/295102/3783329?p=Name%2C%2C%2C20%2C1%2C0%2C0

Ignacio

--
Este correo electrónico ha sido analizado en busca de virus por el software antivirus de Avast.
www.avast.com

I don't have their data sheets, but I have a bunch of the capacitors you describe...as in maybe a thousand of them?

I vaguely remember hunting down enough data to read them about a decade ago. It was not too hard to find on the wonder-web.

I can describe the technique I use with those tektronix capacitors.
I concluded that with a standard soldering iron you can only create a problem here,
in the way that after excessive pushing on the PCB, the foil will separate from the PCB.
Using stronger solder iron also creates a potential danger of destroying the PCB.
Using solderwick will not give the desired results because the holes are large, and there is also solder on the other side of the PCB.
So even a good cleaning on the visible side, leads to the damage the pcb on the other side (the inaccessible one), if it is withdrawn by force.
I use a soldering iron with a power of about 60W, but in such a way that I strictly take care NOT to touch it to the pcb,
but only to the visible part of the electrolyte can.
After 5-6 seconds, this stronger soldering iron will have the power to melt the solder from the invisible side as well,
and then it is easier to pull it out with a pump.
Pre-adding low melting point solder, which someone already mentioned here,
is one of the things that will help a lot if you have it.
It is a good idea to take something for practice, some part where there is such an electrolyte or simply place such an electrolyte on a similar plate,
which is not a shame to destroy by experimenting.
Getting the can well heated without touching the pcb takes a bit of practice.

On a whim, I purchased a lot of (9) 7000 Series plugins. Quite cheap for the plugins that were in there. On my bench now I see a lot of Intel badges and calibration data from the mid 80s. In the lot were a 7A29 and a 7B15. My fastest mainframe is a 7854 so this outperforms my current abilities. But Tektronix purchases don't come with addiction warnings so I accepted the risks when I started this a few years ago. I have a lot of parts to track down for calibration (like a 7104 someday). But I'll bide my time by tying up simpler loose ends first.

I'm curious about the Wiltron VSWR Autotesters. I tracked down this data sheet It apparently came with a graticule that I would need to track down as well.

I'm gathering that the model numbers on these devices follow a specific format: ##X## Where the last two digits is the expected DUT input impedance and the middle letter is the connector type. I'm guessing that the first number is an identifier based on the series? Would I be correct in assuming the following two things:
1. If the SWR tester is rated for the bandwidth the manual calls out (in this case, the 10MHz to 1GHz), then the series won't matter and any 'XXB50' device should work?
2. That technically, with an appropriate adapter the connector doesn't contribute as much to the SWR and therefore any XX#50 Wiltron VSWR Autotester should work, so long as the bandwidth meets or exceeds requirements.

This is, step B7 in the cal and is technically just a performance verification. So I suppose I could skip it. Of course, I'm no professional and this is a hobby. But I enjoy learning the art of electronics in this way and I don't mind the tedium. It makes me appreciate it more. For the sake of the art, does anyone have insight on these devices?

The closest I've found is this device. But I can't find any data sheet on the 11 Series.

The longer I do this, the harder it becomes to track down this or that calibration device or 067- adapter. I'm beginning to consider I may have to make my own if I ever want to complete an adjustment on a lot of these devices.

I've never heard of Saugamo. Sangamo made a line of what you're
describing. Some capacitors in that case style were paper capacitors.

covers these obsoloete styles, as well as a lot of old US Army TM manuals
for electronics such as for the TS-382 test set..


On Wed, May 15, 2024 at 9:07?PM garp66 via groups.io <hrgerson=
[email protected]> wrote:

Looking for .pdf's of SAUGAMO Silver Mica dipped molded Capacitor
data sheets or Catalogs ?

-- red rubber type dipped silver mica ) capacitors, with P/N's,
specifications.
( Red rectangular capacitors with 6 small ( "o" )'s on them, ... older
unit would have had colored painted dots indicating values.

.pdf's of Saugamo Electric Co. CM15- dipped silver mica capacitors
Or any other Saugamo Series ?

example:
Some older units labelled "CM158300J" in black ink, on the red 'rubber'
'plastic'
( no colored dots, but the six ( "o"'s ) still present on the
rectangular package. )
perhaps CM15-8300
.... so guessing 8300pF @500V @ 5%

Newer Saugamo dipped capacitor Part# "designators" appear to have
additional letters, as in the following sheet:



thank you,