Tek 7603 readout repair

[Martin.M]

hello friends,
I am more familiar with tube oldies, this 7603 is a new thing on my table.

There is no readout comming, I need to know how to make the measuring in the  readout board to catch the bad IC there.

!! I am pretty shure to have the readout ICs all in stock, but I don`t want to destroy a new one, so I need the test.

Here are enough scopes present to do that 

greetings
Martin

[capt bullshot]

First, I'd check if the readout is turned on at all. Maybe by watching the horizontal deflection signal in auto trigger mode, free running at a medium timebase setting. If the readout is active, the ramp signal gets interrupted by the readout, this is clearly visible.

Then check the inputs and outputs of U2126 (Timer) - this is the one controlling the whole readout system. Of course, check the power supply voltages of the readout board.  Check the readout intensity input, if it varies with the setting of the readout intensity knob. Check the setting of the readout mode switch (S2110) on the board, set it to "free run".

At the moment, and with the information you give, I'd suspect the readout doesn't get turned on or failure of the master controller chip (that would be the "Timer"), maybe the S2110 in triggered mode (the readout won't display if the scope isn't triggered)

[dave_k]

What version of the readout board do you have? There were a couple of different versions produced during the production lifetime of the 7603...

[Martin.M]

ouch 

I have opened that 7603 now and think now there is no readout board installed.
But the scope have at front the pot readout intensity, and there is no "N" or Option 1 to find outside.
Or I am to stupid to find the board, that may be possible

I have a readout borad in my spares collection, 670-1900-06
but no cables to install that in the 7603
Martin

[capt bullshot]

Maybe you're able to build your own cables, the Tektronix Peltola connectors are simple
http://w140.com/tekwiki/wiki/Peltola_connector
but if you don't have some, I don't know where to get them. I'd try to stick some coaxial cable with rigid inner conductor into the sockets without the gold piece. The others can be made of single row precision contacts like these:
https://www.reichelt.de/Buchsenleisten/BL-1X10G7-2-54/3/index.html?ACTION=3&LA=2&ARTICLE=180551&GROUPID=7435&artnr=BL+1X10G7+2%2C54&SEARCH=%252A

Do you know this one:
http://www.amplifier.cd/Test_Equipment/Tektronix/Tektronix_7000_series_mainframe/rep-und-kal-7603/Reparaturbericht%20TEKTRONIX%207603.htm
There are pictures of the location of the readout board

[guido]

I might have the cabling availble. Have a 7603R parts unit. So i would have to check if the cables have the correct length...