exxos's Atari, Amiga & retro forum

Have you checked that the power jack isn't shorted? That was the case with the last broken Spectrum I bought. It's still broken though :D

edit:

I replaced TR4/5 so many times the board just couldn't take it. That was before I bought a de-soldering station though :)

HigashiJun wrote: 14 Sep 2023 08:45 The kind of situation I hate...

BTW, this is probably unrelated to your issue, but have you considered replacing the 7805 voltage regulator with a Traco Power TSR 1-2450 ? Your machine will run much cooler than ever.

I had a Traco Power regulator in my Oric ATMOS and it did wonders...

Yes, I'm considering getting some Tracos, though the 7805 is working and I do have a bag of spare 7805's and I feel that they are a little overpriced.

However, I'm more than a little peeved with myself because I made a schoolboy error, and this shows the risks of doing stuff late in the day after you got up at 05:30 and did a long day because of a long commute to the office.

Below are the pinouts of the original transistor (On the left) and the alternative (On the right):


The specs match, but the pin orientation doesn't, and because it was late and I didn't pay attention, the replacement went up in smoke. Luckily I have an 'ammo' belt of the replacements, so had another to fit, however I now have no +12v or -5v at the 4116's. Nor do I have it at the LM1889 socket either...

So I'm paying the price for pressing on when I was tired, but it happens to us all. I need to go print out the schematic for that section of the circuit and try to figure out what I may have killed.

rubber_jonnie wrote: 14 Sep 2023 10:23 So I'm paying the price for pressing on when I was tired, but it happens to us all.

Welcome to my world :P

exxos wrote: 14 Sep 2023 10:31

rubber_jonnie wrote: 14 Sep 2023 10:23 So I'm paying the price for pressing on when I was tired, but it happens to us all.

Welcome to my world :P

Thank you for your support :)

@rubber_jonnie

Yes, doing something when you're tired after a long work day always leads to mistakes...

I tend to think that work days should be forbidden by the law.

:lol:

HigashiJun wrote: 14 Sep 2023 11:12 @rubber_jonnie

Yes, doing something when you're tired after a long work day always leads to mistakes...

I tend to think that work days should be forbidden by the law.

:lol:

I quite agree!!

So a quick update on the 'RJ Breaks his Spectrum +' saga.

I took a look at the board closely and spotted this:


Can you spot the diode that isn't dioding any more?

I removed it and it fell apart:


Luckily it's a 1N4148, of which I have many, so I'll drop one in and see how we go.

And we didn't go anywhere, still no 12v or -5v.

Hope you'll find what's going on quickly and make your machine run smoothly.

HigashiJun wrote: 14 Sep 2023 12:36 Hope you'll find what's going on quickly and make your machine run smoothly.

Thanks, me too!!!

Careful @rubber_jonnie or @PhilC will be after you for taking over his job .. :fire: :fire: :fire: :hide: