havols
Well-Known Member
Hi Audiokarma Members
I wrote from Manaus, Brazil.
I have here a Pioneer sx 828, in great condition.
Here in Manaus, Brazil, is hard to find some technician to do a good service on this vintages amps.
So, I've learned a lot with a help of audiokarma friends, and myself have did maintenance of my integrated and tube receiver and amplifier.
In this sx 828:
Except the 2 main caps, I replace all others eletrolitic caps, and a little transistors by AF-UNIT and HEAD-AMP-UNIT.
In the main amp Unit, i just replace the eletrolitics caps.
I regulated the bias Voltage
BIAS 11-17 PIN: 18mV
BIAS 12-18 PIN: 21 mV
When i power on the receiver, it sounds fine for about 4 minutes, the Bias voltage increase to 29mV, and stabilizes in this value.., and after some minutes, the relay click ON (no sound), and after a time, the sound return.... and the relay click on again, no sound... and sound return...
2 Main Caps are original. Follow the voltages on power supply
PIN = Voltage on SCHEME = Voltage by this sx828
2 = 12V = 12.2V
4 = 4.5V = 4.3V
5 = 32V = 30.9V
6 = 31V = 32.4V
7 = 35V = 34.6V
14 = 44V = 45.5V
15 = -44V = -45.4V
17 = -45V = -46.1V
The voltage on Wall is 117V (120V on receiver)
If anyone can help me, i will appreciate.
Best regards
I wrote from Manaus, Brazil.
I have here a Pioneer sx 828, in great condition.
Here in Manaus, Brazil, is hard to find some technician to do a good service on this vintages amps.
So, I've learned a lot with a help of audiokarma friends, and myself have did maintenance of my integrated and tube receiver and amplifier.
In this sx 828:
Except the 2 main caps, I replace all others eletrolitic caps, and a little transistors by AF-UNIT and HEAD-AMP-UNIT.
In the main amp Unit, i just replace the eletrolitics caps.
I regulated the bias Voltage
BIAS 11-17 PIN: 18mV
BIAS 12-18 PIN: 21 mV
When i power on the receiver, it sounds fine for about 4 minutes, the Bias voltage increase to 29mV, and stabilizes in this value.., and after some minutes, the relay click ON (no sound), and after a time, the sound return.... and the relay click on again, no sound... and sound return...
2 Main Caps are original. Follow the voltages on power supply
PIN = Voltage on SCHEME = Voltage by this sx828
2 = 12V = 12.2V
4 = 4.5V = 4.3V
5 = 32V = 30.9V
6 = 31V = 32.4V
7 = 35V = 34.6V
14 = 44V = 45.5V
15 = -44V = -45.4V
17 = -45V = -46.1V
The voltage on Wall is 117V (120V on receiver)
If anyone can help me, i will appreciate.
Best regards