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Yeah it's kinda tricky to do it with analog board installed, what I did is measure voltage, pull analog board out, make very small adjustment, install analog board, measure voltage again, repeat a few times and you can get the voltage spot on. For glued pp1 i just replace them with precision...

Agree with what @jonschultz said before regarding B2 voltage. Also first thing you need to do before adjusting geometry is to adjust the trimmer PP1 near the crt power supply and make sure you get 8.3V/24V/84V on secondary outputs, you can use test points labeled TP1/TP2/TP3. Usually when you do...

Have you reflowed all solder joints yet? That will rule out connection issues. if so then I guess you have the same bad transformer as I do. From my previous research, the transformer probably has a loose or cracked core which creates harmonics in the audible range, making the sizzling sound...

Ah yes I had the same issue on my LC520 (shares the same chassis as LC550/575 other than the caddy CD drive). Got the machine in non-working state and after recap it boots up but has the same buzzing/sizzling sound as yours, but much louder. Found the source to be the switching mosfet and...

I assume you are repairing the analog board of se30 right? Check -12v output of psu and on logic board. if there's no -12V you won't get any sound as the opamp used for audio amplification requires -12V. For analog board A, trace Vsync signal with an oscilloscope, make sure it reaches TDA1770...

Horizontal width is controlled by the width coil, not potentiometer. I assume you are talking about the vertical height of the image, in that case clean the height adjustment potentiometer with contact cleaner, make sure it's not damaged and is actually turning, you should see the wiper arm...

If you've already checked voltage and clock signal on Egret, then it could be a dead EGRET chip. iirc on classic ii Egret chip is surrounded by several electrolytic capacitors and it's prong to electrolyte corrosion. You can try to swap the Egret chip into another working board or compatible Mac...

Stumbled across this reset issue on an SE FDHD and made a post a while ago, it will get stuck at checkerboard pattern on powering up for ~10s, then it chimes and boots up as normal. Turns out I put a much larger capacitor at C36 by mistake when recapping, used 47uf instead of 1uf. My theory is...

Not on a se30 but I got this problem on a color classic, alternating white and dark lines are constantly moving from top of the screen to the bottom. Check the video and if you look closely you can see them crossing the bottom edge of left window at the beginning and around 3-4s. Hard to capture...

Just to add my 2 cents, I managed to fix a few conner and quantum drives with melted rubber bumper on the magnet, just wrap a few layers of Kapton tape around them and that's it. Tried to clean the goo once but made a huge mess, so never gonna try that again... For those quantum drives with...

Have you tried the headphone output? Is the sound clear on both channels? If so the opamp that drives the internal speaker or the speaker itself might be faulty. If only one channel is clear then one of the sony sound chips isn't working, otherwise either both sony chips or ASC at UE10 is...

Should be easy to add a few extra pads and use jumper wires to reconfigure secondary winding connections to achieve 60V, 68V and 84V +B. Sense lines can also be made reconfigurable with jumpers. Also on HDMI output, the main issue with those cheap VGA-HDMI adapters is they only accept 31KHz...

Try to remove the ram expansion board and boot with 1MB onboard ram only, then run a memory test with snooper, see if it reports any error, although from my experience ram failure is always reported on boot up.

Good job. In your schematic you marked DL1 as BZX84-C8V2 which is a 8.2V zener diode. I also checked the schematic made by @jonschultz which marked DL1 as BZX84-B36, a 36V zener diode. Which one did you use to get it working? Also seems XC1186B does have xray protection, DL3 is fed by a sensing...

That's normal, unlike main power supply that has feedback control on the secondary, ctr power supply is regulated only on the primary side, it will fluctuate quite a bit as load changes. IIRC on standby +B is about 70-80V, so your reading is ok. Don't think xc1186b has x-ray or +B protection...

If HOT is not shorted and CRT PSU does not enter protection mode after it tried to start initially, then the fault might not be in the horizontal output stage. Did you check the main power supply and see if it works well under load? And +5V standby voltage? Also check POWER_SAVER signal coming...

Did you check your ram sticks in another mac? Or put known good rams in it? Pretty sure it's a ram issue, I had an se showing the exact screen (sad mac with alternating texts) due to a bad ram stick. Apparently ram chips can go bad after sitting in storage for a long time. Sockets can also...

Nope, without adjustment the picture is slightly compressed horizontally, vertical size remains the same. Makes sense as vertical/horizontal size is set to 512x384. To adjust aspect ratio to 560x384 I have to shrink vertical size since horizontal size is already at its maximum, so I will end up...

I do have a 520 logic board installed in a cc chassis, and I can confirm you can switch resolution to 560x384 in monitor settings: And switching to 560x384 does work, the screen shifts a bit to the left and compresses horizontally. However, the first time I tried to switch to 560x384 crashed...

I think those are jumper pads to bypass headphone detection in the 3.5mm jack: If you short them sound should be routed to the opamp for speaker output even a headphone is plugged in. Do you have sound from headphone jack? If so double check the opamp circuit, also clean the headphone jack...