Source for DEC TC01 (and similar) bulbs?

[Michael Thompson]

>
>
> From: Josh Dersch <derschjo at gmail.com>
> Subject: Source for DEC TC01 (and similar) bulbs?
>
> The Search Scope loop diagnostic shows block numbers going by in both
> directions so a lot of the drive and controller are working, but there's
> some glitchiness in bits 2, 5, 8, and 11 of the data so I need to trace
> that down; I hope it's not the tape head.
>
> - Josh
>

 So what do bits 2, 5, 8, & 11 have in common? All bits come from the same
track on the tape head, and share some of the path to the Data Buffer.

If you wrote this tape on this system, I would try reading a tape that was
written on another machine to make sure that the problem didn't originate
with writing.

Check for a bad connection where the tape head cable connects to the G851
module in the TU55, where the G851 plugs into the TU55 backplane, and where
the data cable plugs into the TU55 backplane, and possibly the K2 relay on
the G851.

In the TC01 you could swap the G888 module in slot C22, the S205 module in
slot D05, the S205 module in slot E06, the S603 module in slot C02, or the
R123 module in slot E08, with another one to see if the glitch moves to
another bit.

-- 
Michael Thompson