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Re: R205 100 ohm resistor in SR98 starting to get hot and smell
Posted: 16 Nov 2018 12:35
by Icky
exxos wrote: 16 Nov 2018 12:34
Icky wrote: 16 Nov 2018 12:19
DONE - Recapped and re-metal filmed
:bravo:
Thanks - that was a fun easy relaxing Atari morning whilst waiting for half a dozen other jobs to finish :)
Re: R205 100 ohm resistor in SR98 starting to get hot and smell
Posted: 16 Nov 2018 12:50
by PhilC
It is funny how we can find some jobs stressful but others relaxing, even if they are more complicated.
My missus thinks I'm nuts fixing computers to relax.
Re: R205 100 ohm resistor in SR98 starting to get hot and smell
Posted: 18 Jan 2020 00:32
by atari030
G'day, I've been reading, reading and more reading a bit about PSU's lately. And this thread popped up a few times. Couple of quick questions, if a modern floppy is used on an old PSU, can that cause issues? I'm starting to think it would cause some 12v drama and it might explain a few odd things I've been seeing with Mega PSU's and the like.
I am about to rebuild an STe PSU with the same hot resistor dramas.
Re: R205 100 ohm resistor in SR98 starting to get hot and smell
Posted: 18 Jan 2020 01:07
by exxos
12v isn't used on modern drives, only really old brick style type stuff. I would suggest you check out here
https://www.exxosforum.co.uk/forum/viewforum.php?f=17
Re: R205 100 ohm resistor in SR98 starting to get hot and smell
Posted: 18 Jan 2020 10:41
by atari030
I did read some posts where you mentioned dummy loads on the Mongrel boards due to a lack of 12v on the floppy. I couldn't see that in your mandatory fixes though. I'll keep looking. Would that cause a PSU not to kick over?
I'm going to dump a 5w resistor in R205 on my STe PSU. The current 3w one is in burnt fingers territory. I might place D203 under the board as there is heaps of room to clear it from the PSU plate.
Re: R205 100 ohm resistor in SR98 starting to get hot and smell
Posted: 18 Jan 2020 10:52
by exxos
atari030 wrote: 18 Jan 2020 10:41
I did read some posts where you mentioned dummy loads on the Mongrel boards due to a lack of 12v on the floppy.
I think you must be confusing 3 subjects there... dummy loads are for testing the PSU. Resistors on the PSU are to load it while nothing is connected else it would probably explode otherwise. Mongrel 12V I was talking about trying to not use 12V at all, or a small step up converter from 5V.
Re: R205 100 ohm resistor in SR98 starting to get hot and smell
Posted: 18 Jan 2020 11:30
by atari030
No, I understand that. If you use a standard STe (or FM) PSU with low or no 12v load, what would be the impact of that?
R205 I'm just doing while I recap the PSU as its roasting.
Re: R205 100 ohm resistor in SR98 starting to get hot and smell
Posted: 18 Jan 2020 13:42
by exxos
atari030 wrote: 18 Jan 2020 11:30 If you use a standard STe (or FM) PSU with low or no 12v load, what would be the impact of tha
No, it won't matter.