German Translation Needed: Bias Setting for Denon PMA-520

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DreadPirate

DreadPirate

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Joined 2006
#1
This is the bias setting procedure on the PMA-520 (see link below). It's in German and I've been able to make out a good deal of it, but if someone could annotate my procedure below so that I don't miss the finer points, would be appreciated:

Initially set the following:

Power- OFF
Volume- Minimum
Loudspeakers- Discconnected (A and B)
All other settings at midpoint

1.- Don't understand this.
2 thru 4.- Turn Power ON. Measure at TP1/TP3 with voltmeter. At 10 seconds: .5mV +/-.2mV. At 5 minutes: 3mV +/-.5mV. At 15 minutes: 5mV +/-.5mV. Adjust VR403 (L) and VR404 (R) for these values.
5. Inject a 1KHz/100mV signal into the tuner input and turn Volume to maximum.
6. (For PMA-520) Measure at TP2/TP4 with voltmeter. Adjust VR405(L) and VR406(R) to 20mV +/-3mV.

Imageshack - pma720germanprocedure.jpg

The image does not read well on the screen, you will have to download and open in a viewer. Right click the image and use the "Save As" command to save it to your computer. Sorry.
 
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#3
1.- Don't understand this.
2 thru 4.- Turn Power ON. Measure at TP1/TP3 with voltmeter. At 10 seconds: .5mV +/-.2mV. At 5 minutes: 3mV +/-.5mV. At 15 minutes: 5mV +/-.5mV. Adjust VR403 (L) and VR404 (R) for these values.
5. Inject a 1KHz/100mV signal into the tuner input and turn Volume to maximum.
6. (For PMA-520) Measure at TP2/TP4 with voltmeter. Adjust VR405(L) and VR406(R) to 20mV +/-3mV.
Click to expand...

Turn Power ON. Wait 10 sec. Measure at TP1/TP3 with voltmeter. Adjust to .5mV +/-.2mV using VR403 and 404. Wait 5 minutes and adjust to 3mV +/-.5mV. Wait 15 minutes and adjust to 5mV +/-.5mV.

Inject a 1KHz/100mV signal into the tuner input and turn Volume to maximum.
Measure at TP2/TP4 with voltmeter. Adjust VR405(L) and VR406(R) to 20mV +/-3mV.
For 10 min. keep adjusting VR405 and 406 to keep 20mV +/-3mV.

Pretty basic bias adjustment 😉
 
#5
BIAS CURRENT

-Setup
1. Install device in a normal position and protect from direct draft of A/C or fans.Carry out adjustment at a room temperature between 15°C and 30°C.

2. Set control elements to the following:
POWER BUTTON -> OFF or STANDBY
VOLUME CONTROL -> CCW [counter clockwise] until stop
SPEAKER TERMINALS -> open (connect neither speakers nor load resistors or similar)

-Adjustment:
1. Open top cover, then [put a] DC voltmeter on the measuring points of PCB number 1U-1608-1 (EQ.- and amplifier module).
2. Plug in power plug and switch power button to "ON". Within 10 seconds turn up VR403 (left channel) and VR404 (right channel) so much, that the voltmeter shows 0,5 mV +-0,2 mV.
3. Warm up for 5 minutes, then adjust VR403 and VR404 so thet the voltmeter shows 0,3 mV +- 0,5 mV.
4. After 15 minutes of warming up, adjust VR403 and VR404 so thet the voltmeter shows 0,5 mV +- 0,5 mV.
5. Apply a signal of 1 kHz and 1V RMS and turn up volume to maximum.
6. Now the voltmeter should show a slightly higher value (max. about 10 mV), now adjust the trimpots VR405 (left channel) and VR406 (right channel) so that the voltmeter shows 20 mV +-3 mV.
7. After another 2 minutes, adjust VR405 and VR406 to 35 mV +-3 mV (PMA-720) respectively 20 mV +-3 mV (PMA-520).
8. After 10 minutes of warm-up, adjust VR405 and VR406 to 40 mV +-3 mV (PMA-720) respectively 20 mV +-3 mV (PMA-520).
Click to expand...

I hope I got it all right.
 
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#6
The 100mv signal to set the bias, is that typically vpp or vrms? I'm using a meter without rms capability to measure the output of a cd player playing a 1kHz tone and using the volume control to vary the output. This is my signal generator. If vrms, then I need to read 282mv on my meter.
 
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