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Attempting to recreate a Tektronix Test Card

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Zenwizard:
I am diving in to the deep end of the pool and seeing where this goes. I have a Tektronix 7854 that I would like to do a full calibration on so I can use it on the bench. But there seems to be a very illusive card that I need for the calibration. A 067-0912-00 Test card. This card allows for the 7854 to be operated without the digital sections installed in the frame. But it allows all the analog functions to work as well as channel switching and specifically the vertical amplify thermal compensation. To be adjusted. If I can get a test card or make a replacement test card I am considering a re-cap of the 7854 to make is last the long term.

I have run in to a snag. The test card uses a 74LS314 1024-Bit Random Access Memory (RAM) ic. Is there a modem version of this chip or am I dead in the water? I am very familiar with digital logic but I have never really had to use ram before so in uncharted territory at least for me.

Attached in the only data I have been able to locate for this card.

Thanks in advance for the advice.

radix:
That's a 7, not 1, so those are 74LS374, which you should have no trouble sourcing.

They're also listed in the part list as an octal D FF and you can also look up the Tektronix part number in the Tektronix Semiconductor Cross Reference when in doubt.

Zenwizard:
Well... I missed that one. I will continue to work on the card now Thanks.

Renate:
That's a pretty simple button latch.
The pullups on the right are only necessary if you want to do the "all bulbs on" test with jumper P430.
(You can test them individually by just hitting the eight buttons.)

Me? I'd probably just use an Atmel ATMega328P µC.
One chip and you're done.
(And you could make it do chasing lights too.)

Zenwizard:
Renate a micro would work however There is something else that the board does that is very critical other then test the lights. If all it did was test the lights I would not really care due to mine already being replaced with LED’s. I found soft white to be a good color for the scope.

The other function of the board Is to control the analog circuitry without the digital board in place. This allows the chassis to be run as a analog unit with out any of the processing. The test board is used only in this scope so they are super rare in the wild. It also required analog terminations for several signal lines to keep everything will behaved.

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