Dead psu where to start diagnosing?

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rubber_jonnie
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Re: Dead psu where to start diagnosing?

Post by rubber_jonnie »

Groppo91 wrote: Sat Mar 30, 2024 11:51 am
rubber_jonnie wrote: Sat Mar 30, 2024 10:37 am

It's certainly possible that the schematics don't show it as fusible, but it definitely is and it's fusible for a reason. I used a Bourns in one of mine.

No the item marked TDK is a transformer, the transistors are the items connected to the heatsinks and are better tested removed from the board, but shouldn't be mixed up. I would say that if you're not sure about what the components are, then you probably shouldn't be working on PSUs, they can bite you badly.

I don't mean this in a mean way by the way, but having been bitten by various PSUs over the years, my advice is usually if you're not sure, don't touch them. It's your choice of course, but I always err on the side of safety first.
Thankyou, I did electronics as part of my qualification but was back in 2010 so have a small understanding and feel happy testing it/ replacing part. One of the transistors has been swapped as part of the recap process so will test the remaining one when I get a moment.
I always like to be sure people are prepared to work on PSUs as they can be a bit of a pain :)
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Groppo91
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Re: Dead psu where to start diagnosing?

Post by Groppo91 »

Update on the PSU,

I have put that one aside for now and stripped out my other one which had cracked board and decided to fit a pico psu using the original switch. I now have a working psu to test the 3 Atari computers that I picked up. So far managed to boot 2 from the new psu yet to try the last one. So that is an stfm and an ste which boot fine. The mouse I have didnt seem to work with the usb adapter I found an old school mouse that has a switch for amiga and st which has broken parts but works enough to test the ataris. One floppy drive seems to be faulty, the keyboards I think one is faulty as the alt arrows did nothing. The other one moves the cursor but seems to lock up.

I have purchased the diagnostic cart from the store to hopefully check everything a bit further, not sure how to use it yet but look forward to the arrival. My next purchase will be some device to allow me to run software/games from usb/hdd not sure what my options are in this space so any recommendations would be great.
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exxos
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Re: Dead psu where to start diagnosing?

Post by exxos »

https://bbansolutions.co.uk/ is a hard drive I can recommend. Atari world seems a bit flooded with all sorts of drives lately though. But I can vouch for bban as I did a lot of testing personally. It's one of the cheapest as well.
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
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Re: Dead psu where to start diagnosing?

Post by Groppo91 »

exxos wrote: Fri Apr 12, 2024 2:38 pm https://bbansolutions.co.uk/ is a hard drive I can recommend. Atari world seems a bit flooded with all sorts of drives lately though. But I can vouch for bban as I did a lot of testing personally. It's one of the cheapest as well.
Ah thankyou, wished I saw that before placing my order earlier. I am new to it all so documentation is a big thing for me to learn. I see the user manual is still in draft mode for that one. I take it the device replaces the floppy drive?
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Re: Dead psu where to start diagnosing?

Post by exxos »

Groppo91 wrote: Fri Apr 12, 2024 3:50 pm Ah thankyou, wished I saw that before placing my order earlier. I am new to it all so documentation is a big thing for me to learn. I see the user manual is still in draft mode for that one. I take it the device replaces the floppy drive?
It plugs into the Hard drive port on the back of the ST. You need the floppy to copy files to it. Unless your buy a better driver like HD11 to allow files to be copied to the SD card directly.
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
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Re: Dead psu where to start diagnosing?

Post by Groppo91 »

exxos wrote: Fri Apr 12, 2024 3:55 pm
Groppo91 wrote: Fri Apr 12, 2024 3:50 pm Ah thankyou, wished I saw that before placing my order earlier. I am new to it all so documentation is a big thing for me to learn. I see the user manual is still in draft mode for that one. I take it the device replaces the floppy drive?
It plugs into the Hard drive port on the back of the ST. You need the floppy to copy files to it. Unless your buy a better driver like HD11 to allow files to be copied to the SD card directly.
Oh cool I see what is the benefit to hdd over something like a floppy emulator?
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Re: Dead psu where to start diagnosing?

Post by exxos »

Groppo91 wrote: Fri Apr 12, 2024 4:11 pm Oh cool I see what is the benefit to hdd over something like a floppy emulator?
Not something I can personally answer. I don't use a floppy emulator. Comparing a hard drive to a floppy emulator is really down to personal preference and usage. It's one of those things like trying to compare petrol and diesel engines to me. Maybe someone else can list the pros and cons but I don't believe anyone ever has.
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
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