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It's the same arrangement as all of the compact Macs used, at least up until the SE/30 which is the newest one I've poked around in. With the early machines up to the Plus, the power supply and monitor were both integrated into the same PCB.

14.3182 MHz is exactly 4x the NTSC colorburst frequency, and is commonly used in devices that generate NTSC video. That does tend to suggest that this is a video card of some sort, although it's also possible that like the 3.57MHz colorburst crystals, it was a mass produced part, making it...

That won't really tell you much, since we know it isn't overcurrent causing the trip. If the Mac were drawing enough current to trip the branch circuit, the power cord would be getting hot. It has to be leakage current from hot to ground, bypassing neutral, and it's probably only a few mA, far...

I've never seen a bad transformer in a switchmode power supply, ever. I also find that usually when I start to suspect a hard to find/exotic/expensive component, the actual fault turns out to be something simple. IIRC the IIe supplies are self-oscillating converters where a resistor provides...

I've seen that happen with antique radios and I'm sure it does with other stuff too. Some idiot will take something that's complete and worth a bit, then tear it apart and try to sell the individual pieces. Usually one or two parts are in demand and sell but for much less than the complete unit...

You might try some automotive upholstery cleaner, the kind you spray on foamy then scrub with a towel and wipe off. I've cleaned similar bags by running them through a gentle cycle in my front load clothes washer with no problems, but YMMV. If you take it to a dry cleaner or fabric shop...

I have yet to hear of a single case of someone being electrocuted by the EHT in a small CRT monitor. Note that this is NOT an excuse to be careless, you *can* get hurt, but the biggest risk is tearing your hand open or falling and cracking your head on something when you jump back. *ALWAYS*...

I've been using SCA server drives, the 2.5" Seagate Savvio models are my current favorite as they're very quiet and reasonably low power despite being 10K RPM drives. The adapter PCBs to connect them to a 50 pin SCSI bus are only a few bucks and the drives are currently plentiful enough that...

I've done it, although not with anything as complex as a whole motherboard. I x-ray the PCB, use a multimeter, visual inspection, datasheets for the ICs, and a bit of intuition. It takes a lot of patience and a good eye but it's certainly possible. If you don't care about reusing the board...

I really doubt it has anything at all to do with the flyback transformer, that is on the secondary side of the power supply. Look for film capacitors between live and ground near the input power connector. No need to fear the CRT. The zap from that feels like a strong static electricity shock...

The light on the card tells you that there is power to the slot, but there are multiple power rails of different voltages, one or more could still be dead.

This is different. The filter capacitor you are referring to is the DC filter capacitor used to smooth the pulsating DC coming from the rectifier. A discharged capacitor has a very low impedance and acts much like a short circuit until it charges up, something that can take long enough to blow a...

Relax, the ground/earth connection is a secondary safety system, intended to protect the user in case of a fault condition such as an internal short between a live wire and exposed metal parts. Obviously I'm not advocating permanently disconnecting the ground pin and leaving it that way, but...

Find the SRAM chip that stores the data and measure the voltage at the power pins with the machine unplugged. You should see >3V from the battery between the power pin and ground of the IC. It's possible the IC is bad, but I would first suspect a connection or the diode that isolates the...

What sort of circuit is this on? Unless it is overloaded with other devices, I doubt that over-current is tripping it. Is the breaker a GFCI (RCD in Europe) or AFCI? Both of those are somewhat notorious for nuisance trips, especially older generations. It's not uncommon for the noise suppression...

I would definitely go over the deflection yoke connector carefully, and check the pins too, they frequently heat up and corrode, which makes them heat up even more. If that looks ok, there's a non-polar electrolytic capacitor in the horizontal deflection circuit that can fail. Since the HV...

My friend had the same cap blow up in a similar manner in his Apple II. They're wired directly across the AC line so when they do short, the failure can be pretty spectacular, but usually no other damage is done. Make sure you replace them with the correct type of capacitors, something rated for...

How about looking at the video generation circuitry used in the B&W compact Macs? Schematics are out there, it's a simple, elegant design, built from commodity parts. It would make a reasonably starting point. Another option is to use one of the various CRT controllers that were used in...

I think you'll find that the rubber bands will deteriorate in relatively short order. I had some hanging on a tack at work for about a year and when I went to use one eventually I discovered they had all dried out and fell apart in my hands. I use rubber grommets as vibration isolators. You can...

Just because something can be physically plugged in doesn't mean that it will work. The IIgs monitor uses NTSC scan rates, 15 kHz horizontal and 60Hz vertical. The lowest resolution the LC supports is around 24 kHz horizontal, it's a completely different format.