Gladen XL no Bias
Hi there,
years ago i bought a broken Gladen amp. I tooked it to a guy, i thought he know what he does. It came back with horrible solderpoints and its not working.
Rails +- 45V, at the TLs at pre-amp i have +- 9V.
Output transistors get no bias. Across drive-transistors (AH-16/BH-16) B->E 0,5V.
I stuck a bit. Any schematics or something? Audio Systems 280.2 and 300.2 are very similar to this.
Thanks
Hi there,
years ago i bought a broken Gladen amp. I tooked it to a guy, i thought he know what he does. It came back with horrible solderpoints and its not working.
Rails +- 45V, at the TLs at pre-amp i have +- 9V.
Output transistors get no bias. Across drive-transistors (AH-16/BH-16) B->E 0,5V.
I stuck a bit. Any schematics or something? Audio Systems 280.2 and 300.2 are very similar to this.
Thanks
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Found this schematic in another Gladen thread.
Measured the voltages against GND.
Measured the voltages against GND.
Attachments
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Most of these GT Trading amps use the same basic protection circuit. Attached are two diagrams that may help f you don't have anything closer.
Hi Perry, thanks for your reply.
I found the problem seconds ago.
I build the shown circuit in a digital electronic circuit simulator.
That show me which voltages i have to measure.
Zener ZD82 + ZD83 both broken. I only have 7,5V Zeners here, but in this short test the amp run. Now i can order the right parts.
Have you ever seen a PSU with two PWM-IC´s?
Thank you very much
I found the problem seconds ago.
I build the shown circuit in a digital electronic circuit simulator.
That show me which voltages i have to measure.
Zener ZD82 + ZD83 both broken. I only have 7,5V Zeners here, but in this short test the amp run. Now i can order the right parts.
Have you ever seen a PSU with two PWM-IC´s?
Thank you very much
Yes but that doesn't apply to this amp, does it?
If it's for a different amp, start a new thread.
If it's for a different amp, start a new thread.