Took Apart My TS1000 - I Have Questions

[DrVenkman]

I would definitely replace the 7805 if you are going to use it a lot. It makes a huge difference.

Yep. I already did the same with my ZX81. I used a Traco TSR 1-2450. It’s a tight (very tight!) fit against the corner of the case top, but it fits, if only barely. If I were to buy more of these specifically for this application, I’d probably get the 90 degree angle version (TSRN 1-2450A), but it’s about twice as much per unit, which doesn’t make a lot of sense to me. There’s gotta be something in the data sheet to explain it, but I’m not going to go looking for it right now.

An example of a crazy drunk chip is here

Mark

Wow. That’s a pretty poor job of board-stuffing.

[Lardo Boffin]

I use MuRata regulators (I get mine from here http://retroleum.co.uk/spectrum-repairs-mods) as they are generally around £5 and fit well.

[DrVenkman]

So I finished the composite board for the TS1000 today and - after realizing I’d installed the BC548 backwards (D’oh!), I get a nice sharp image. Unfortunately, and unlike my ZX81, I’m getting jailbars. Drat. Where’s the most likely source of noise on this style of board? I have plenty of .1uF ceramics on hand I can use as decoupling caps to help reduce the video noise.