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Hello Allen,
If you're after an "In circuit Transistor Tester" in general, might I
suggest you try Silicon Chip magazine in Australia.
Their September 1993 issue has a project for that very thing.
If you live in Australia you can purchase the issue and have it delivered.
If not, you can buy the...
Hello eagle1109,
You'll probably find that the capacitor in question is not shorted.
It seems to be in the same circuit as the shorted diode. Check the capacitor
out of circuit or lift out one leg, then measure it.
That diode might be the only culprit that's preventing the unit from working...
Hello eagle1109,
I have to agree with betwixt in regards to the chopper transformer being faulty.
You need to check the two small electrolytic's in the primary of the power supply for
high ESR or lowered capacitance.
Also measure any high value resistors in the primary, that perhaps are used for...
Hello Cap_J,
I'm unsure of the material the resistor on the left is made of, but those
types are commonly the fusible ones. Designed not to flame up. Just go
open circuit instead.
Regards,
Relayer
You can if you're trying to neutralize alkaline contaminants.
The vinegar is temporarily used to neutralize and clean up any alkaline on the exposed metal.
It's not on long enough for it to start eating anything away.
Regards,
Relayer
Smart arse.
From a reputable pinball machine repairer in the States.
Joe's Classic Video Games. Look it up. He's been in the business for years.
By the way, I doubt very much you've ever repaired a thing in your life. You're all "theory" and
nothing else.
Relayer
Hello neazoi,
There would be nothing wrong with Q502 (BU407), as you would be measuring R507 (4.7Ω) resistor in the circuit.
This is measuring between the base and emitter.
I also doubt that there would be anything wrong with T501. It is possible you could have shorted turns, but unlikely.
Try...
Hello Bob,
I would highly recommend you use some white viniger soaked into a used toothbrush to neutralize the acid from the backup battery spill. Then clean it with isopropyl alcohol to remove the rest of the viniger.
Use Kynar wire for your trace replacements. If you're in Australia, you can...
Hello Abbeykutty,
Check this link:
https://www.service-manual.net/?download=66535-yamaha-psr-e433-psr-i455-service-manual
Don't expect this to be free of charge. Most manuals these days you have to pay for.
Regards,
Relayer
Hello specmaster.
Check the following link for the Function Generator:
https://www.elenco.com/wp-content/uploads/2017/10/FG-600K_REV-G-2.pdf
I hope it helps.
Regards,
Relayer
Hello Paul98,
Here are equivalents for the following:
2SC1162:
2SC2877
2SD1380
2SD1818
2SA715:
2SA1217
2SB1009
2SB1217
All of the above have similar characteristics, and some equivalents have better ratings
than the originals.
I hope the above helps.
Regards,
Relayer
Hello rosaage,
Setting your multimeter on low ohms, measure between D141 cathode to ground,
same for D142 and D143.
Did you try measuring TS152 for opens or shorts?
Please let us know how you get on.
Regards,
Relayer
Try removing each capacitor in turn to determine if any have short circuited.
If removing the caps makes no difference, then it's definitely something else.
Possibly the power to theIC/s, if they use the 3.3 volts as Vcc.
Regards,
Relayer
The 12 and 13 are the waveform numbers.
Waveform 12 is the critical one. It's the horizontal out signal. You should be able to match up the waveform
with the one shown on that rail (12). I have to admit, details are not the best, but the basic shape and amplitude
you should be able to see...
That's strange that you couldn't find those diodes.
Could you please let me know what is the exact part number of the horizontal output transistor.
You need to physically look at the part.
I have to agree. Unless you can obtain a cross-hatch test pattern, I'd leave those rings alone.
At this...
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