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Will Cheyney

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  1. Will Cheyney

    Macintosh SE/30 screen "shimmering" issue

    Fab, good to know @jessenator!
  2. Will Cheyney

    Macintosh SE/30 screen "shimmering" issue

    Thanks @blusnowkitty. No luck though. I've tried disconnecting the HDD power and booting from a Floppy EMU and the issue is still present.
  3. Will Cheyney

    FDHD dead motor

    Does the read head motor try and move at all anymore? It can be removed/replaced independently but it would probably be easier to find a whole replacement drive than just the motor.
  4. Hi all. Looking for some technical advice from you all. I have a Macintosh SE/30 that has a very minor issue with the display. It appears that when the machine is seeking data from the HD, a very faint horizontal shimmering line effect moves up and down the screen. So faint that I can't even record it to show you. There is no "worming", distortion or burn in on the display otherwise. I doubt the majority of people would even notice it but I'm curious as to whether anyone knows what a potential issue may be. The logic board has been recapped and I'm planning on doing the Sony PSU tomorrow incase it's a voltage regulation thing (testing the voltage on the floppy port shows small fluctuations). Any ideas? Thanks!
  5. Hello @MindWalker I recently fixed a 120V Macintosh that I had been given who's previous owner had plugged it into a European 240V outlet. It went bang. I managed to fix it so perhaps the failed components that were on my effected board will be the same! Firstly, the fuse had blow so I dropped in a replacement 2.5A glass cartridge fuse. After asking around and doing some testing with my multimeter I found that CR23, CR25, R47 and R49 had failed. I replaced CR23 and CR25 with new 1N4007 rectifier diodes and R47 and R49 with 1/4W 1.5 Ohm carbon film resistors. And that was it! It worked again - being sure to use a step-down voltage converter though! I recapped the entire board for good measure as well. Luckily all the components are readily available and inexpensive. Good luck. Let me know how you get on.
  6. Will Cheyney

    HELP: 120V Macintosh Plus analog board blowing F1 fuse

    @Joe This is a HUGE help. Thank you. The black mark on the top of LF1 isn't related to it being burnt. It's some kind of marking that appears on this component. The highlighted resistor is just black in colour. In fact, no component is burnt/scorched. No funny smells either. I'll give the rest of your trouble shooting a go and report back. @JDW Thank you for your reply too. I've checked the voltage output of the converter and it's right on the money. It's also at 60Hz and has a rating of 100w. No no issue there.
  7. Will Cheyney

    HELP: 120V Macintosh Plus analog board blowing F1 fuse

    I’m hoping someone with past experience in a similar issue may be able to make some suggestions ☺️
  8. Will Cheyney

    HELP: 120V Macintosh Plus analog board blowing F1 fuse

    @LaPorta that’s what I’m doing and it’s causing the fuse to blow every time. I’m using a 240V to 120V step down voltage converter (with an adequate wattage rating).
  9. Will Cheyney

    HELP: 120V Macintosh Plus analog board blowing F1 fuse

    @jjclay Being based in the UK I’m used to the international boards - this is the first time I’ve come across a US 120V board. They’re are a number of differences in the layout and components. I replaced the fuse with an exact match to the original (and what is stated on the board). 2.5A 250V. The voltage converter I’m using is brand new and the 120V output checked out just now. All the resistors you mentioned I check all gave the same reading on the multimeter so I assume we can rule those out. I did a good job with the soldering and reflowed the usual places that can suffer from dry/cracked joints. This is all helpful though - I’m learning! Pictures of the front and back of the board attached.
  10. Will Cheyney

    HELP: 120V Macintosh Plus analog board blowing F1 fuse

    Thank you! @jjclay The analog board I have is the 630-0102- J dated 1986. I replaced the RIFA paper caps at C33 and C37 but the larger cap at C38 was already a red poly cap so decided to leave it as was. I didn’t get any magic smoke just a flash of the fuse blowing. I understood that these board can’t be converted to 240V?
  11. I'm trying to rescue a US 120V Macintosh Plus that was gifted to me. The previous owner accidentally connected it to a 240V UK mains power supply without a step-down transformer. Whoops! The original 2.5A 250V fuse had clearly blown so replaced it at the same time as doing a complete recap. When I did the "smoke test" just now (and this time I made sure to the use the correct step-down voltage converter), the fuse blew again so something somewhere isn't right. Would anybody be able to help me diagnose what the issue could be? Just as a side note, the logic board works fine in another Plus so luckily that wasn't fried by the original mishap. Thanks for any help in advance Will
  12. @tokyoracer I should have mentioned, I live in the U.K. so that’s why something blew on the board when it was plugged directly into our mains 240V supply. As far as I know, it doesn’t boot any more when using the correct 240 to 120 step down converter. I haven’t been able to examine it for myself yet but wanted to get a head start on searching for a replacement if needs be. This led me to the idea of whether it’s possible to convert from one voltage spec to another - even if it meant replacing a few components on the board.
  13. Looking for some advice from the Macintosh community collective mind. Some one has kindly offered me a Macintosh Plus that is a US 120V spec. They recently got it out of storage and forgot to use a step down voltage converter when connecting it up. Unsurprisingly the machine no longer powers on. Firstly, I haven’t attempted a repair like this before and was wondering what the extent of the component damage could potentially be. And secondly, could the analog board be permanently converted to International spec (220-240V) to negate the use of a voltage converter in the future? Thanks!
  14. Will Cheyney

    Macintosh Classic I Analog Board replacement capacitor list

    Yes please - sounds ideal! ☺️ Thank you.
  15. Hi folks. Can anyone point me in the direction of an exhaustive list of the the capacitors found on a Macintosh Classic I analog board? I’m surprised I haven’t been able to find a resource anywhere online that lists all capacitors found within the compact Mac’s... unless there is and I just haven’t found it! Many thanks.
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