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Luxman R-117 Turn On Thump, trying to figure out problem

mbz said:
With the unit powered off I assume Pin 6 was 0Vdc, C758 is only 1uf so nothing to discharge (D760 orientation appears incorrect). Also assume Pin 6 immediately jumps to 9.15Vdc, ie wanted delay of 2seconds not observed.

Plz confirm immediate jump from 0V to 9.15Vdc, no 1-2second delay

I'm stumped, the amp appears to work as designed, had a look for service bulletins... Appears that a delay at power on needs to be added for the speaker select relays, possibly adding a cap on pin 6 (with a bleed resistor??), possibly better would be to cut traces (see yellow below) and take audio feed from pins 3&5, this is above my pay grade maybe one of the techs can propose a solution.

Fig below tries to illustrate problem.
Green line, Usual audio out from power amp through protect relay RY655
Red line passes audio to speaker select relay
Blue line is power for speaker select relays, through zener to spkr switches then onto Q651,2, appears to be no delay
Yellow line, possible solution??? take audio from after the speaker protect relay which includes a power on delay C655
Click to expand...
Damn, I do not know. But the 9.1V is immediate. The first time I did it, I had the speaker A switch off. It did not happen. It's almost like there is a signal that is being sent to the speaker a switch? I just can't figure it out. Maybe I am overacting to this noise.

Here is the ultimate question though. For people that have a R-117. How long after turn on do you hear and witness, the speaker output the relays clicking on? I do not believe it is at power on from what i have read. So something is outta whack somewhere.
 
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33713 said:
Damn, I do not know. But the 9.1V is immediate. The first time I did it, I had the speaker A switch off. It did not happen. It's almost like there is a signal that is being sent to the speaker a switch? I just can't figure it out. Maybe I am overacting to this noise.

Here is the ultimate question though. For people that have a R-117. How long after turn on do you hear and witness, the speaker output the relays clicking on? I do not believe it is at power on from what i have read. So something is outta whack somewhere.
Click to expand...

When you power on it clicks immediately then after about 6-8 seconds it clicks again and the volume knob light comes on and its ready to go. Thats without A or B speaker buttons on.
 
LHorn said:
When you power on it clicks immediately then after about 6-8 seconds it clicks again and the volume knob light comes on and its ready to go. Thats without A or B speaker buttons on.
Click to expand...
The unit has a standby state for power up using remote control. Basic health check is performed and if ok main power is supplied to entire amp, this will be the immediate relay (RY701) click at power on. The 6-8second delay should be for the protection circuit, mute timing or maybe waiting for dc offset to subside.

The test needed is to power up with either/both A, B Speaker buttons on. Warning this may produce a loud pop so suggest disconnect speakers and connect a multimeter between red and black speaker posts, either L or R channel, set MM to 20Vdc scale, expect to see a flash of numbers at power on.
 
mbz said:
The unit has a standby state for power up using remote control. Basic health check is performed and if ok main power is supplied to entire amp, this will be the immediate relay (RY701) click at power on. The 6-8second delay should be for the protection circuit, mute timing or maybe waiting for dc offset to subside.

The test needed is to power up with either/both A, B Speaker buttons on. Warning this may produce a loud pop so suggest disconnect speakers and connect a multimeter between red and black speaker posts, either L or R channel, set MM to 20Vdc scale, expect to see a flash of numbers at power on.
Click to expand...

Yes the way I understood it is when you first hit the power button is when the four 10000uf caps charge up (hence dimming of house lights) and system checks.

What is the purpose of RY655 then? It looks like its tied to the speaker outputs as well.
 
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LHorn said:
What is the purpose of RY655 then? It looks like its tied to the speaker outputs as well.
Click to expand...
RY655 is the main speaker protection relay, controlled by IC651 (TA7317P) and thermo sensors TH501,02.
Located between amp outputs and speaker selectors.

Would appreciate if you could run this test on your unit, appears the OP unit is operating normally (or I've missed something)
mbz said:
The test needed is to power up with either/both A, B Speaker buttons on. Warning this may produce a loud pop so suggest disconnect speakers and connect a multimeter between red and black speaker posts, either L or R channel, set MM to 20Vdc scale, expect to see a flash of numbers at power on.
Click to expand...
 
mbz said:
RY655 is the main speaker protection relay, controlled by IC651 (TA7317P) and thermo sensors TH501,02.
Located between amp outputs and speaker selectors.

Would appreciate if you could run this test on your unit, appears the OP unit is operating normally (or I've missed something)
Click to expand...

Ah OK...good to know about RY655...thanks.

I tried that test...left channel then right channel of speaker A...volume all the way down....MM set to 20Vdc...and nothing happened with first click of power on and nothing second click of unit ready status...never showed any voltage flicker at all.

Neither of my 117's ever thumped at power up....they did very slightly on power off but just a soft thump.
 
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