Oscilloscope question

[Philip Pemberton]

In message <m1DK1qR-000IxxC at p850ug1>
          ard at p850ug1.demon.co.uk (Tony Duell) wrote:

> 465, 466, 468, etc. Smaller, portable. I think the 468 is a storage 
> 'scope, one of that series is, anyway. No plug-ins. Transistorised. 

The 466 and 468 are both storage scopes - the 466 is electrostatic (analogue)
storage, the 468 is digital storage. I've got a 466 here - it's a lovely
scope and parts are still available from various people (Deane Kidd for one).
I should know - I've just had to buy a new knob for the horizontal position
control on my 466 after slipping while adjusting the handle... the scope flew
forward and the knob got cracked. I didn't notice the crack until the knob
shattered completely :(

If you're after the custom chips, Sphere Research (<http://www.sphere.bc.ca>)
have got stocks of some of them.

The only part that IIRC is difficult to get for 466 scopes is the motor for
the cooling fan. I suppose you could replace the motor/impeller assembly with
a 120mm axial blower though.

> The manuals have really gone down for more recent 'scopes. You don't even 
> get a schematic now...

Ah, but the 466 manual has pull-out schematics and parts lists for every
single major module (basically every single PCB). I try and avoid recent
hardware due to the lack of schematics and service data, although the same
applies (to a lesser degree) to older equipment. I'm after a maintenance
manual for a Solartron 7150 - I've got the operator's manual but I want the
schematics for reference (in case I end up fixing it at some point). I also
want to know which chip(s) to pull and read out in an EPROM burner. Firmware
ROMs don't last forever :)

Speaking of which, the Tek 466 manual also includes a hex dump of the 6301
(?) PROM that runs the storage subsystem. Tek even included a state
transition diagram...

Later.
-- 
Phil.                              | Acorn Risc PC600 Mk3, SA202, 64MB, 6GB,
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