Check the preamp. transistors.
Without preamp. R246 not burned : Problem is in preamplificators.
Yes it's works fine,two channels ok.
Only big noise clack on right speaker with relay when I make Amplifier power on or off.
The sound is very good,no distortion.
Only big noise clack on right speaker with relay when I make Amplifier power on or off.
The sound is very good,no distortion.
I. INITIAL ADJUSTMENT (No load connected) A. OUTPUT OFFSET VOLTAGE
1. Connect a DC Millivoltmeter to L Channel speaker output terminals.
2. Turn unit “ON” and adjust VR101 (100ohms) to get a reading on IC107 Pin 1, which must be <100mV.
3.Connect the DC Millivoltmeter to R Channel speaker output terminals and adjust VR102 (100ohms) to get a reading on IC108 Pin 1, which must be <100mV
I don't understand,need two multimeters?
One on speaker terminal and second on ic107.....
1. Connect a DC Millivoltmeter to L Channel speaker output terminals.
2. Turn unit “ON” and adjust VR101 (100ohms) to get a reading on IC107 Pin 1, which must be <100mV.
3.Connect the DC Millivoltmeter to R Channel speaker output terminals and adjust VR102 (100ohms) to get a reading on IC108 Pin 1, which must be <100mV
I don't understand,need two multimeters?
One on speaker terminal and second on ic107.....
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try to connect multimeter to output terminals (speaker connection). try to adjust OUTPUT OFFSET VOLTAGe.
what is the voltage? when speakers are not connected.
If it's too small. perhaps 1,2milivolt. Perhaps, some capacitors may be dead. 22.000uf or c154? But, this is new for me. I have a very small click when open the NAD. Is delay circuit working?
what is the voltage? when speakers are not connected.
If it's too small. perhaps 1,2milivolt. Perhaps, some capacitors may be dead. 22.000uf or c154? But, this is new for me. I have a very small click when open the NAD. Is delay circuit working?
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Offset voltage it's ok 2-3 mV.
But very big pop sound on right channel power on and off.
22000uf it is one per channel?
But very big pop sound on right channel power on and off.
22000uf it is one per channel?
you are right. I don't know up to now.
what about IDLING CURRENT? must be arount 5mv. Between TP101 and TP102? and 3&4?
what about IDLING CURRENT? must be arount 5mv. Between TP101 and TP102? and 3&4?
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Is there some dirt (leakage?) under C139 (or C140)?
Look, right and left channal's caps different?
Look, right and left channal's caps different?
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