restoring a Silent 700 Model 765

Cameron Kaiser spectre at
Sat Mar 19 18:10:14 CDT 2022

I found my old Model 745 in storage and other than needing a print head clean
and adjusting the printer contrast, it works splendidly. It has the manual and
I've got some plugs to build it an RS-232 connector when I find some more round

This whetted my appetite for other 700s, including the (in)famous bubble memory
763/765. I was able to land a set of 765 ASRs. One of them came with Telenet
transcripts from The Source (various logins from 1978 to 1980), which was
really cool reading. I'll scan these.

However, neither of them work. Both power on, but they immediately go into
COMMAND mode and sit there, which appears to be abnormal behaviour based on
what I'm reading in the service manual (thanks, Bitsavers!). The NUM LOCK
switch works and the paper advance works, but nothing else appears to elicit a
response. One of them advances the page and acts like it's printing the command
prompt, but the other one doesn't even do that.

The service manual suggests I need to replace both the TMS 9980 and 8080
boards, which would really suck. I'm hopeful that the one that's "more active"
has a working 9980 board and I can use the 8080 board from the other one. (I
haven't even gotten to the bubble memory yet.) Anyone repaired these units or
have an idea of a repair strategy other than replace damn near everything?

303 8A


@C 301 24


------------------------------------ personal: --
  Cameron Kaiser * Floodgap Systems * * ckaiser at
-- Simplicity is the ultimate sophistication. -- da Vinci ---------------------

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