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  1. But I rather prefer to use a small ATX + PNP222, see below. I removed the ATX PSU from it's original case otherwise it did not fit into the Apple's one. I rotated 90 degrees the fan to let the case support to pass through, yes I realize it's not very efficient, but I'm glad if someone has better ideas. Respect to the previous project here I could pass the 220V to the CTR plug. What is not solved, but I could, is to add a relay to interrupt the 220V to the CRT as in the Apple original PSU.
  2. It was a successful project, see attached pics. The PNP2222 is behind the picoATX, it serve the purpose of "inverting" the SP logic. What is not solved, but I could, is to add a relay to interrupt the 220V to the CRT as in the Apple original PSU.
  3. thanks @PowerMac_G4 pal for the encouragement, I'll definitely try ... Yes, I recapped some already with success, except for a PowerMac 6200. Nice list of yours ... PF
  4. Larry Pina's book does not help. For all the symptoms when the SE is silent with a black screen he is mentioning to check against for the Analog Board, but in my case it can not be, so even if the board looks tidy and neat I will go for the replacement of the capacitors. May the force be with me PF
  5. you are right @tjjq44, I was expected to apply an Apple upgrade, but I was wrong. I'll not mangle with my Mac II. Thanks for sharing you POW best PF
  6. HI all, I'm in process of repairing a Mac SE that does boot, it does not play chimes, the CRT quickly flashes a pattern of with squares and then it rests in peace blank and silent. I did the following: I added a new battery I checked the diodes, all just fine All the caps looks tidy with no sign or leakage. I put the motherboard in the chassis of a working SE, same outcome I put other know to work RAM, same outcome I replaced the ROM with another set from a known working SE, same outcome for a sort of regression test, I put back the
  7. Hi @Rjp663, unfortunately not. The voltages are all a couple of volts below the optimal value, despite my many attempts. The PP1 trim does not affect the voltage, as I reported in more detail above. I have replaced almost everything, I'm now considering to replace it with a ATX + DC regulator and inject the currents in the AB as @mogs did. best PF
  8. Me too, just to say thank you all!! This is a very precious forum and thread The 220V AC to 12VDC is a 120W transformer for LED strips. The picoATX is 90W. In the original setting the PSU could turn the CRT as well. In my case it is collected directly to the 220C in (not shown in the photo) Since I do not use an external cards and an internal HD I believe the power provided is enough. The PN2222A is under the picoATX.
  9. Hi @mogs, in this picture you left all the capacitors close to the speaker, but in a following one some have been removed (e.g. Cp2 CP36..) and also the inductance. Apparently IP3 has been removed as well because from the picture I can not tell, can you please list which components you removed or you left? Specifically the part on the left obscured by the cabling. What about PP1, DP14, DP3 and Dp4, cant' they be removed as well? To my understanding those are to feed to optocoupler. thanks
  10. Hi all, I wish to replace the PSUs of my Mac LC, Mac IISI with the following: LED PSU 10A (120W) providing the 12V [1] + picoATX 90W [2] .... I do not use HDs but only SCSI2SD 1) in the LC the CRT is not powered by the Mac 2( I do not connect the CRT to the PSU of the IISI. It's PSU is rated +5 , 6.8A (35W) I'm wondering about the Watts, is this a doable right? many thanks indeed [1 ]https://www.amazon.it/gp/product/B0748DGM6N/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1 [2] https://www.amazon.it/gp/product/B00
  11. Just to say that I got the VRAM ... my LC works just fine now! Thanks you all
  12. I'm also interested in a couple of mAcTX LC, are they still available? thanks all the best PF
  13. Dear all, I'm recapping the non working PSU of a LCIII. I checked the optocoupler[1] by testing pins 1,2 which correctly shows a diode. But the 4, 5, 6 does not show a NPN transistor, so I assume it's bad. I'm not able to find it or any equivalent PS2561-1/PS2501-1, NTE3041. (I am waiting for the new capacitors, so I can not test the PSU with the original PN111) Can some electronic expert advice on what can I use? thanks so much [1] https://pdf1.alldatasheet.com/datasheet-pdf/view/43321/SHARP/PC111L.html
  14. Hi all, I got two pizza box Mac IISI one M0360 S/N CK1250JRC53, the other M0350 S/N SG1427DYL13, in the cases it's written IISI. The back of the case is different because in one case the ids are engraved in plastic, in the other it's a plastic stick. http://macfaq.org/serial.html kindly tells me that the first was assembled in Ireland in 1991, the latter in Singapore, same year, but the mother boards I found inside is written "Assembled in Ireland". The serial number on the logic board is not fully readable but the last 4 chars are the same for both. The mother boards
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