DSP508 half voltage output fix

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exxos
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DSP508 half voltage output fix

Post by exxos »

I've had a couple of the DSP508 which are only outputting half voltage (under load) ..

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It was found in both cases a bad joint on the heatsink, which is being used as part of the mains circuit it seems :roll:

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Re-soldered..

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Done! The voltage is showing higher than it should as they battery is going in my meter, but it's actually 5.02V!
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
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Re: DSP508 half voltage output fix

Post by exxos »

The very similar ASP34 suffers from bad joints on the heatsink as well...

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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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kodak80
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Re: DSP508 half voltage output fix

Post by kodak80 »

Thank you @exxos I had a PSU here that was outputting half-voltages under load. This made me check the heatsink pin soldering and I found a crack so re-soldered all heatsink pins and viola the PSU is working again and outputs normal voltages again. :cheer:

PSU solder crack - half voltage under load is the result (kodak80).jpg
PSU solder crack - half voltage under load is the result (kodak80).jpg (268.56 KiB) Viewed 1533 times
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