Tektronix 067-0542-99 Sine Wave Generator

[steven2605]

Hello all and Happy New Year!

New to the blog so I'm not sure if I'm the right place. Looking for manual for an old Tek sine wave generator (067-0542-99). Checked tekwiki and they had a schematic and a calibration bulletin. Both hard to read. Found another copy of the calibration bulletin crisp, clean and in color! But alas, the info is a bit short in that the info on parts location and test points is missing. The unit I found is super clean, original and for the most part working. Would like to avoid reverse engineering it if can find the info.

[perdrix]

The place to ask about Tek stuff is: https://groups.io/g/TekScopes.   Some of the folks there have forgotten more than I know (and I've been messing with Tek 'scopes and other stuff for 20 years) ...

David

[TERRA Operative]

Do you have a copy or link to the clean calibration bulletin?

I can upload it to Tekwiki for future reference if you do.

[factory]

Unfortunately some Tek manuals do lack detailed parts location drawings, I've had to work it out the hard way before.
The pictures here have some parts labelled, https://www.pa4tim.nl/?p=1305 of course no guarantee they were all the same over the years.

David

[steven2605]

Thanks all for the response. First up, thanks to David for the link, the picture are awesome and a great starting to identify where thing are at. I have copied the photos will post them in pdf format. The clean calibration procedure will also be posted. I tried finding the original link, but no results. I think i just got lucky. 

Since there seems to be some interest, I will keep posting my progress as get time to work on it. The parts unit I ordered just in case arrived today. The first unit (the nice clean one) checked-in very well. After warming it up, I was able to get fairly accurate signals on all ranges, except there is no output on the 100 kHz range.

[steven2605]

Top View

[steven2605]

Calibration procedure

[factory]

Thanks all for the response. First up, thanks to David for the link, the picture are awesome and a great starting to identify where thing are at. I have copied the photos will post them in pdf format. The clean calibration procedure will also be posted. I tried finding the original link, but no results. I think i just got lucky. 

Since there seems to be some interest, I will keep posting my progress as get time to work on it. The parts unit I ordered just in case arrived today. The first unit (the nice clean one) checked-in very well. After warming it up, I was able to get fairly accurate signals on all ranges, except there is no output on the 100 kHz range.

That cal procedure is for the 3B4 (as stated at the bottom of each page), it's from here. https://w140.com/tekwiki/wiki/3B4

I would be checking the multiplier switch on the 100kHz position, could be dirty switch contacts or the capacitor for that range.

David

[steven2605]

Opps!! Thanks David. Guess missed the first rule...

I did clean the usual suspects, including the range switch with DeoxIT. The working functions seemed a bit cleaner, but still no output from the 100 k range. Checked all the caps on the range switch with 4 lead LCR meter (the only one I have with no two lead option) and all checked out.  Did start checking the others the main board, but quit when could not reach some with the 4 lead kelvins. Looks like I have do disassemble the face to remove the hidden screw that hold the frame rail, a job better done with a fresh start and cup of brew. Have not had chance to compare the pictures with the component tags to try and zoom in on an area that might be the issue.

Do have a question if anyone knows. Given the era I'm not sure if is soldered with silver. 

[steven2605]

 ...silver solder. Also not sure about the adjustable cap and it's sister in parallel. The values are not given on the schematic I have.

[factory]

The ceramic tag strips use silver based plating, they recommended a tin/lead solder with a small percentage of silver, use of ordinary solder can cause damage to the plating, some have seen no problems, but repeated soldering with the incorrect mix will risk dissolving the plating.

Tek did provide a small amount of the correct solder inside some equipment, I've also acquired a small roll of the tin/lead/silver solder for working on the tag strips, before the EU ban on lead based solders for unprofessional  use.

7-45 is printed on the trimmer cap, not sure if it's the range in pF or lower without measurement, there must be a value on the parallel cap too, seems these are only switched in the 100kHz position, might be worth checking for short circuits here too.

David

[steven2605]

Just short update... Decided to check in the second unit, what I was calling a parts unit. The price was very cheap didn't expect it work be a working unit. It is bit ugly on the outside. Well even a dog get a bone sometimes. After cracking it open, I found it pretty clean inside. Much to my surprise, it functions on ranges and voltages, just needs some tweaking to bring it into spec. Not bad for $40.00 US shipped.  Will post when do more work on the first unit and plan to do some time in AutoCAD to clean up the schematic.

[factory]

Always the same, look for a parts unit then find out it's working fine, at least you can now compare between the units.

I found a trimmer cap with the same markings of 7-45, it measures in pF.

David