Hi guys
I'm missing SA501 and SA502. Are these a TVS diodes ? They were badly burnt but I could still read something like 3 stripes red green red. I highly doubt it's a 3 band resistor of 2.5KΩ. They are being used in the preamps section in between the RCA shield and the secondary ground of the transformer. I 've also found that the traces from the secondary gnd to the RCA shield have been blown up.
The amp is Philips xp480. I do not have the schematics.
Any ideas ?
I'm missing SA501 and SA502. Are these a TVS diodes ? They were badly burnt but I could still read something like 3 stripes red green red. I highly doubt it's a 3 band resistor of 2.5KΩ. They are being used in the preamps section in between the RCA shield and the secondary ground of the transformer. I 've also found that the traces from the secondary gnd to the RCA shield have been blown up.
The amp is Philips xp480. I do not have the schematics.
Any ideas ?
Attachments
Sadly no. i've even had to google what is variac. never needed one so far.
I'm not 100% sure if this is my issue, but since the blown secondary gnd trace to the TVS and the soot the in them, I thought this was it
For sure it's a pre-amp issue, nothing reach the op amps (the have the proper +/-15v) all 4 channels.
Injecting signal into the amplifier section bypassing the preamp works.
I'm not 100% sure if this is my issue, but since the blown secondary gnd trace to the TVS and the soot the in them, I thought this was it
For sure it's a pre-amp issue, nothing reach the op amps (the have the proper +/-15v) all 4 channels.
Injecting signal into the amplifier section bypassing the preamp works.
Attachments
Do you see any signal on the RCA terminals where they go into the board?
Does that signal reach the other end of the wires for the preamp signal?
As a side note, the colors for the TVS are orange on both ends and that's simply the material that the device is made of. It's the same orange as on other glass diodes. The only stripe is green and you may never know what that means.
One more note. If you come across a cheap variac, buy it. Variac + bridge rectifier and capacitor = good high voltage variable DC supply.
Does that signal reach the other end of the wires for the preamp signal?
As a side note, the colors for the TVS are orange on both ends and that's simply the material that the device is made of. It's the same orange as on other glass diodes. The only stripe is green and you may never know what that means.
One more note. If you come across a cheap variac, buy it. Variac + bridge rectifier and capacitor = good high voltage variable DC supply.
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