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New Tektronix Curve Tracer Adapters - Semiconductors and Vacuum Tubes


pinefloor@...
 

Hi Everyone!

I've been a proud owner of a Tek 576 for about 6 months or so now but I recently became increasingly frustrated with using minigrabbers to hook up DUTs so I decided to design some new test fixtures. I've tried to stay true to the form factor of the original Tektronix types but I'm not in a position to have plastic boxes made custom. So I've compromised with a dual layer PCB design. This leaves a bit to be desired from a safety standpoint but I figure curve tracer users should already be knowledgable about their high voltage/ current capabilities.

I currently have three types available if anybody is interested: A small signal outline, a flat/ tab/ inline type, and one for vacuum tubes with 9A/ 9AJ basing (12ax7, 6922, etc.) I have them listed on ebay here:

https://www.ebay.com/itm/264951846052
https://www.ebay.com/itm/264953083999
https://www.ebay.com/itm/264982302678

If anybody is interested, I'd be happy to sell them direct at a 10% discount.

I have a few more ideas that I'm sorting out, namely fixtures for surface mount transistors, but I'm most curious about what you all would like to see in a test fixture. Do you find the Kelvin connections particularly useful or that you have large measurement errors without them? I plan on making more tube fixtures as well but the solution by Mr. Tillman already covers just about everything you would need.

Anyways, thought I'd share with the group. Thanks to everyone for making this group so helpful and interesting!

-Chris


Jean-Paul
 

Christian bravo pour le projets. Wonderful to see a Tektronix afficanado, who appreciates curve tracers.

I did similar 577, 576 test adapters in 1980s, using two pieces of lucite 1/4" and hand wiring the Bannana plugs.....TO-3, TO-66, TO-220 and TO-247(?) also, power diode, and a very useful binding post adapter. But I didn't have your tube socket idea.

The Kelvin connection four terminal is critical for high current tests, 2 terminal will give substantial errors in the voltage at the contacts points. The two terminal limits are perhaps one amp. 576 with 177 pulsed test fixture has 1000A peak capability!

Note...The 576 and 577 plastic safety test fixture cover is easy to damage and a problem in testing large power devices or with long leads. I modified my 576 with an interlock "cheater" switch..DANGER DO NOT DO THIS... At the time I was designing and manufacturing 12 kw arc lamp power with 55 kV ignitors, so the 576 voltage was not worrying!

The 576 is still in mint condition, I got the original manuals, 177 pulsed current and SCR turn-off time adapter.

Keep up the fine work. Just the ramblings of an old retired EE

Jon


Glydeck
 

Very nice. Your adapters look first rate. — George

On Dec 21, 2020, at 5:03 PM, Jean-Paul <jonpaul@ix.netcom.com> wrote:

Christian bravo pour le projets. Wonderful to see a Tektronix afficanado, who appreciates curve tracers.

I did similar 577, 576 test adapters in 1980s, using two pieces of lucite 1/4" and hand wiring the Bannana plugs.....TO-3, TO-66, TO-220 and TO-247(?) also, power diode, and a very useful binding post adapter. But I didn't have your tube socket idea.

The Kelvin connection four terminal is critical for high current tests, 2 terminal will give substantial errors in the voltage at the contacts points. The two terminal limits are perhaps one amp. 576 with 177 pulsed test fixture has 1000A peak capability!

Note...The 576 and 577 plastic safety test fixture cover is easy to damage and a problem in testing large power devices or with long leads. I modified my 576 with an interlock "cheater" switch..DANGER DO NOT DO THIS... At the time I was designing and manufacturing 12 kw arc lamp power with 55 kV ignitors, so the 576 voltage was not worrying!

The 576 is still in mint condition, I got the original manuals, 177 pulsed current and SCR turn-off time adapter.

Keep up the fine work. Just the ramblings of an old retired EE

Jon