Nad 705 repair

My other 705 got here! Came with a missing plug and a pair of speaker cables.

Popped it open to clean it up on my professional cleaning station. Our trash bin.

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All clean.

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Serviced by ohm on the 15th of the 6th 1999 aparently. *Edit* That's a nine drawn over a 6 so 15-6-1999. how confuse being in the year 1999 with 1996...

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All setup and lookin' pretty.

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And I re terminated the speaker cables which are much nicer thicker gauge than what I had before.

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FM is definitely dead, just static like the seller said, the FM muting doesn't seem to be working either. AM works though.
 
Ok guys heres what I got for the tuner in the working 705. IC403 is missing voltages on pins 17 and 18. IC 401 is missing voltage on pin 4. IC 404 has 7v on pin 17 4.5v, on pins 18 and 19, pin 20 has 5v and pin 21 has 1.7v
 
Well, I've been doing a lot of work to the second 705, Replacing some bad caps, touching up solder joints and removing as much dried up glue as I could.

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Glad your are getting work done on the 705. Hope the tuner fix is something easy.

I'm certainly enjoying it. I think the other Nad is a parts unit at this point as I've been robbing all the nice parts from it to make the other perfect. I'm dumbfounded with the tuner to be honest, I've found multiple voltages out of whack but all the components that feed them seem fine, nothing shorted or bad so far. Not giving up yet though, just been a little busy the last few days.
 
Can you do the VCO adjustment . Set the tuner to 87.5Mhz. Adjust L402 till the voltage is 3.0-3.1vdc between TP7 and TP4(gnd). Then check the same points with the tuner set to 108Mhz. The voltage to be 22vdc-25vdc.
 
Can you do the VCO adjustment . Set the tuner to 87.5Mhz. Adjust L402 till the voltage is 3.0-3.1vdc between TP7 and TP4(gnd). Then check the same points with the tuner set to 108Mhz. The voltage to be 22vdc-25vdc.

Nope, it's stuck at 31.5v. across the whole band
 
Can you do the VCO adjustment . Set the tuner to 87.5Mhz. Adjust L402 till the voltage is 3.0-3.1vdc between TP7 and TP4(gnd). Then check the same points with the tuner set to 108Mhz. The voltage to be 22vdc-25vdc.

I've replaced C446, C450 and C445. R451, R452, R453, R454 and R456 all test fine. Same with Q409 and Q410
 
Wonder if the first RF Amp is just at full gain. Since the voltage should vary between 3-22vdc. Have you checked the power supply voltage?
 
Wonder if the first RF Amp is just at full gain. Since the voltage should vary between 3-22vdc. Have you checked the power supply voltage?

All they should be, +35v, +5V, +12v, ground, -15v, Adjusting L402 had little to no effect.
 
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