yamaha cr1000 no sound

If the relay clicks and lamps illuminate at least the 12v regulated supply is at least partially working.
 
There is a + and - 50 volt supply and a + and - 12 volt supply.As well as the B+ and B - unregulated 50 volt power supply. Need to verify if they are working properly or not. I see at least 8 fusible resistors in that part of the power supply.
 
Does the AM/FM tuner show any meter movement or have any illuminated red LED's ?
 
Did you verify that your stand-alone pre-amp and/or power amp were working ? As well as your source ?
 
Around the edge of the power supply board may be some labeled lugs or test points. We need to find the +50 , -50 ,+12 and -12 measurement points.
 
Don't short any pins together or to chassis ground. Bad Juju..
 
Checked all pins voltages on power circuit board as follows 49v, -49v, 10v, 10v. -11v, 11v, -49v, -26v, -50v, 33v., -12v
 
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A recap
- No sound through both spkrs, low hiss through spkrs & headphone
- relay clicks, approx 2mVdc at speaker posts
- Mic volume switch produces popping through the speakers
- no sound with operating the CR as either a PRE or power amp
- voltage/supplies 49v, -49v, 10v, 10v. -11v, 11v, -49v, -26v, -50v, 33v., -12v

Suggest, with CR powered off/unplugged
Set coupler switch set to OFF
measure resistance from Left MAIN-IN RCA (inside) to IN pin on left power amp board
measure resistance from Right MAIN-IN RCA (inside) to IN pin on right power amp board
Set coupler switch set to ON
measure resistance from Left PRE-OUT RCA (inside) to IN pin on left power amp board
measure resistance from Right PRE-OUT RCA (inside) to IN pin on right power amp board

In all cases expect maybe 1 ohm

Both pre/power/both channels affected, psu looks OK, that coupler switch can be a pita.
 
this is when i would do a wet finger test . not recommended if you are are not sure how it works though .
 
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