exxos's Atari, Amiga & retro forum

@rubber_jonnie I did remember that test from my days at college but I've used this as an excuse to get myself one of those cheap Chinese multi-testee that does transistors, mosfets etc.

PhilC wrote: 16 Jan 2025 19:14 @rubber_jonnie I did remember that test from my days at college but I've used this as an excuse to get myself one of those cheap Chinese multi-testee that does transistors, mosfets etc.

TBH I use both as the multimeter is better for parts in circuit.

rubber_jonnie wrote: 16 Jan 2025 21:17

PhilC wrote: 16 Jan 2025 19:14 @rubber_jonnie I did remember that test from my days at college but I've used this as an excuse to get myself one of those cheap Chinese multi-testee that does transistors, mosfets etc.

TBH I use both as the multimeter is better for parts in circuit.

I've got a couple of Flukes and other good quality DMMs thanks to using them at work, been using one of them a lot lately, especially with that monitor.

PhilC wrote: 16 Jan 2025 21:43

rubber_jonnie wrote: 16 Jan 2025 21:17

TBH I use both as the multimeter is better for parts in circuit.

I've got a couple of Flukes and other good quality DMMs thanks to using them at work, been using one of them a lot lately, especially with that monitor.

Good stuff :)

Getting more used to working on CRTs, but my brain is always shouting 'safety first'!!

Well the multi tester arrived and has been useful so far checking the transistors and mosfets on the Reuters monitor.

That and I worked out that the pot marked as set 11v is not talking about setting the wiper to 11v but the output from the PSU pin to 11v. This has helped no end as I now know where to start looking on the HV board as the moment it's powered up with that plug connected it drops the 11v down to 3.5v. Time to go hunting for dodgy components on that part of the circuit then.

So for the monitor I've ordered a Darlington transistor that provides the pulses for the HV.

Then something a little different, I got myself a non working E-MU Proteus/2 from on eBay and have been fixing it.

It needed a PSU recap and a new backlight in the display as it was very hard to see. Unfortunately a standard 16x02 HD44708 didn't want to work as the replacement, so I stole the backlight out of it and fitted it to the original screen. You can't say you can't read it now 8-)

:lol:

Nice find Phil! Despite the bright display!

Im loving how the topics recently have been pivoting over to HI FI audio gear and synths.

mrbombermillzy wrote: 19 Jan 2025 17:57 Nice find Phil! Despite the bright display!

Im loving how the topics recently have been pivoting over to HI FI audio gear and synths.

It makes even more sense when you see the Proteus PCB, powered by a 68000.

In reality, the skills you learn fixing computers transfers pretty well to older synths and sound modules.

fun fact: the Proteus/2 was used to make the X-Files theme tune, that whistle but at the beginning is an instrument called Whistlin Joe.

I ordered a couple more transistors for the Reuters monitor as I was not convinced that the PSU board was working as it should. So I've just fitted them and we now have HV going to the CRT and a picture of sorts.
This is connected to a Been, so it's sort of working with the groups of text in the right place, just got to ungarble it now, time to twiddle some pots :lol: