If not, very carefully measure pin 3 and pin 6 of the power IC against the chassis 0V.
If any voltage is there, the power IC is highly suspect.
If any voltage is there, the power IC is highly suspect.
Great news, i've replaced the 4 rectifier diodes with 1N5402 because i could get those the quickest along with 1N5408 but haven't tried those yet. It's working again so far. After clicking the power button, the lights show up and after a short time the relay clicks in. So i'm hoping everything is ok! 👍😀
I also replaced my multimeter as i didn't fully trust the old one.
So now that the device is open, it might be a good idea to upgrade some components. Any recommendations on wich parts to upgrade?
I also replaced my multimeter as i didn't fully trust the old one.
So now that the device is open, it might be a good idea to upgrade some components. Any recommendations on wich parts to upgrade?
Check the capacitors...and replace the ones around the diode bridge, though it is mentioned above that they were specially made for Technics. But it says 5-71, possibly meaning May 1971, so quite aged.
Your new meter has capacitance function, use it.
And did you actually hear sound through your speakers?
Your new meter has capacitance function, use it.
And did you actually hear sound through your speakers?
So you replace too light rated 3A diodes that failed for new 3A ones as you could get them fastest. Aha. Sometimes I don't understand 2022 logic at all. Nor do I want to for that matter.
Instead of hoping you could use the new DMM (and/or the old one thereby eliminating emotions that it wouldn't be OK) to measure the rails and DC offset on the outputs. That is why those DMMs exist, to check and verify stuff instead of believing/hoping/assuming. Given that it is in capacitance mode on the picture I take you are simply trolling. Don't say you know it has capacitance mode but you did not measure the caps. Even worse is to say you haven't measured anything with the new DMM 🙂
OK, I try to apply the same logic regarding upgrading components. You could upgrade the diodes to 5A types 😀 Another suggestion is to upgrade only the filter caps to larger values so you can then use the new DMM to test the diodes.
BTW that goo in post #63 is a cause of failure in many devices as it becomes conductive. Just a tip. Or hope that it will be OK, that is also possible.
Instead of hoping you could use the new DMM (and/or the old one thereby eliminating emotions that it wouldn't be OK) to measure the rails and DC offset on the outputs. That is why those DMMs exist, to check and verify stuff instead of believing/hoping/assuming. Given that it is in capacitance mode on the picture I take you are simply trolling. Don't say you know it has capacitance mode but you did not measure the caps. Even worse is to say you haven't measured anything with the new DMM 🙂
OK, I try to apply the same logic regarding upgrading components. You could upgrade the diodes to 5A types 😀 Another suggestion is to upgrade only the filter caps to larger values so you can then use the new DMM to test the diodes.
BTW that goo in post #63 is a cause of failure in many devices as it becomes conductive. Just a tip. Or hope that it will be OK, that is also possible.
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Since the SE-A series of amps was build in the 90s I don't think Matsushita would use capacitors made in the 70s.
But that it's just me.
With the P600D (6 Amps 200V) at £0.24 each it makes me wonder...
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Any progress yet? By now you should enjoy the music playing!
Once again, do not over complicate things.
About the 3 A diodes, you can upgrade them to 5A.
It is not a class A amplifier, so the average current draw is not that high, and I do not think that
the Panasonic engineers were that stupid...
Once again, do not over complicate things.
About the 3 A diodes, you can upgrade them to 5A.
It is not a class A amplifier, so the average current draw is not that high, and I do not think that
the Panasonic engineers were that stupid...
It's "Revoxis" amp not mine and according to him it's working but he replaced the diodes with same rating ones (3A).
The reason was i had to know if it was worth it. Instead of bringing it in for repair.
I'm not trolling? I find that a bit strange to be accused from. I came here to figure out what was wrong. In doing so i didn't trust my old meter, and bought a new one. The new one has a capacitance mode, wich i'm using.
As i said before i don't have a whole lot of time.
I checked the large filter caps with the Capacitance mode and it says 9.79mf/9790uf and the other said 9.58mf/9580uf
That is inside limits, so leave them alone.
Impressive, for such old caps, provided your meter is accurate.
Is it working now?
How does it SOUND?
Impressive, for such old caps, provided your meter is accurate.
Is it working now?
How does it SOUND?
I have a some questions regarding the rectifiers, 968driver said to use 1N5408 Wich are 3A but much higher voltage, and others said to use 5A, Why the higher Voltage and Ampere?
Why are these better over the P600B (or 1N5402) ?
The only 5A i can find that i can buy here are STTH5L06
Another i can find is 6A GI758-E3/54
Why are these better over the P600B (or 1N5402) ?
The only 5A i can find that i can buy here are STTH5L06
Another i can find is 6A GI758-E3/54
Fantastic!
I haven't had time to test it yet, i'm waiting on new lights. I noticed the left side of the VU meter lights broke. If i can find some time tomorrow ill test it out.
Put an extra protection circuit, close matched to protect it from surges.
NTC in series, and MOV across AC supply work, there are more complex solutions.
For 240 V, use a 275V MOV, about 8 - 10 mm diameter.
For 110 V, use a 134-140V MOV, same size.
It will clamp the input, protect your system, I think it will be enough for your beautiful system, put it in the junction box that supplies the rack.
NTC in series, and MOV across AC supply work, there are more complex solutions.
For 240 V, use a 275V MOV, about 8 - 10 mm diameter.
For 110 V, use a 134-140V MOV, same size.
It will clamp the input, protect your system, I think it will be enough for your beautiful system, put it in the junction box that supplies the rack.
Use flat top warm white LED from a strip, and a drop resistor as meter lights.
If the supply is 12V, there are cutting marks on strips, 3 LED then resistor. Cut and use.
A little dose of smooth abrasive paper will make the light a bit more diffused.
If the supply is 12V, there are cutting marks on strips, 3 LED then resistor. Cut and use.
A little dose of smooth abrasive paper will make the light a bit more diffused.