I'm in the process of recapping a Falcon PSU with exxos' kit (hoping to tame a ~300 mV ripple on the +12V rail) and after replacing all the caps, I've noticed that my rectifier doesn't look anything like the one in the photo on exxos' PSU page, and also there's a resistor missing from right next to it (R4). (I imagine it's simply not supposed to be there, and this is just a slightly different revision of the PSU. I am also missing R18 in the upper right.)
I am reasonably comfortable with electronics, but not nearly the level of a lot of you guys, so I figured I'd better ask here before continuing. Does anyone recognise this revision of the Falcon PSU, and am I good to continue here and replace the rectifier with the new one from exxos' kit?
Thanks!
Recapping Falcon PSU - My rectifier is different
Re: Recapping Falcon PSU - My rectifier is different
The bridge rectifier is the original square one and is correct. The one Exxos supplies is slightly different but has 4 legs so you need to make sure you align the positive and negative legs:
R4 and R18 was missing from my Falcon PSU and they look the same. Recap worked fine.
R4 and R18 was missing from my Falcon PSU and they look the same. Recap worked fine.
Atari Falcon 030 | Atari 1040 STE | Atari 1040 STFM | Atari 1040 STF | Kryoflux & Supercard Pro Flux boards
Creator of the Atari ST Review magazine archive: https://www.chillichai.com/atari-st-review
Creator of the Atari ST Review magazine archive: https://www.chillichai.com/atari-st-review
Re: Recapping Falcon PSU - My rectifier is different
Yep, no worries on the legs. Thanks for filling me on the other details. I shall continue the project.kodak80 wrote: ↑Wed Sep 19, 2018 11:39 am The bridge rectifier is the original square one and is correct. The one Exxos supplies is slightly different but has 4 legs so you need to make sure you align the positive and negative legs:
R4 and R18 was missing from my Falcon PSU and they look the same. Recap worked fine.
Re: Recapping Falcon PSU - My rectifier is different
Oh silly me. If I'd just looked at the beginning of the Falcon section on the PSU page, I would have seen a picture that matches mine. Good job, me.
Re: Recapping Falcon PSU - My rectifier is different
The differences on the resistor are 110V vs 240V configs.. some better images in this section.
https://www.exxosforum.co.uk/forum/viewforum.php?f=59
https://www.exxosforum.co.uk/forum/viewforum.php?f=59
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.
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.
Re: Recapping Falcon PSU - My rectifier is different
...and it's done.
+12V ripple before...
...and after...
50 mV/div in both cases.
+12V ripple before...
...and after...
50 mV/div in both cases.
Re: Recapping Falcon PSU - My rectifier is different
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.
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: Recapping Falcon PSU - My rectifier is different
Both times just using the load resistors supplied by exxos. "5V uses 2.2R (loads 5V rail with 2.2amps) and 12V uses 10R (loads 12V rail with 1.2amps)"Atarian Computing wrote: ↑Wed Sep 19, 2018 2:45 pm Cool, so from 250mVpp to 100mVpp? What kind of load are you running here?