HELP!!!! TRS-80 Mod III M/B NEEDED!!!!

From: jpero_at_pop.cgocable.net <(jpero_at_pop.cgocable.net)>
Date: Tue Dec 29 13:22:59 1998

> Date: Tue, 29 Dec 1998 21:53:03 +0000 (GMT)
> Reply-to: classiccmp_at_u.washington.edu
> From: ard_at_p850ug1.demon.co.uk (Tony Duell)
> To: "Discussion re-collecting of classic computers" <classiccmp_at_u.washington.edu>
> Subject: Re: HELP!!!! TRS-80 Mod III M/B NEEDED!!!!

> Odd... I've repaired dozens of TRS-80s (Model 1, Model 3, Model 4, CoCos)
> and never had any trouble soldering on the PCBs. Unlike some PCBs I could
> name...

Well, those PCB's are ones that lifts and burns very easily even with
highly care and a lowest temperature possble solder iron station.

The broad traces are wrinkled and bubbled, light green in colour and
coating is easily comes off.

> I hate it when people do that! I'd much rather _repair_ the original PSU
> and keep my machine factory-original than have a machine that the service
> manual no longer applies to. It really annoys me to get a second-hand
> machine with some fault, pull out the service docs, open the case and
> find that they do not apply.

Some switcher PSUs are tandy's make too, I have 4 of them, saw the
service techanical manual on everything including that monster
tranformer.

> What 'Monster Transformer'? Every Model 3 that I've ever seen uses a
> couple of little Astec SMPSUs (and yes, I have worked on 110V-only
> units). Never seen a mains-frequency transformer in one

That transformer is under the floppy, and is about tad under 25"
cubic size. Saw them in few III's. Those III's are very popular in
high school they're by bunches.

> The screening was _optional_ (!). It was added to meet some FCC rule, and
> early units, and units sold outside the US don't have it. Neither my
> Model 3 nor Model 4 have ever had a screen over the CPU board. The tech
> manual mentions this somewhere.

So, add screen forward on. No more blown boards and smelly house.
:-)

> 12" monitor, actually.
Okay.

> -tony
>
 
email: jpero_at_cgocable.net
Pero, Jason D.
Received on Tue Dec 29 1998 - 13:22:59 GMT