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Here she is all dressed up and ready to go !

That looks like corrosive glue. you have to clean that up and replace the parts that it was touching as they most likely are corroded badly . Athanasios

Those are for measuring the heat sink temp for the bias circuit. You have to be very careful with them as their leads brake easily right at the component . And if that happens you SOL , as they dont make them anymore. So you have to put three in series and seal them together in epoxy . I...

2SA968B>MJE15033 Nashou

Thanks for that, I went though all the points and couldn't find where the signal got lost or lower. So At wits end I began looking at the signal out of the volume control board as thats the one board I did not rebuild yet. So while looking closely at it I realized that I had the LI and LF...

All righty then lets get going!!! :D :thumbsup: nashou

Yes, I have the signal at P1,2 and on the Base of TR 901 and 902 and some other places But I can't remember now, I should have taken notes . I'll test more points when I get home. It be cool if someone would trace out the signal paths to help me visualize it. Like I said I have a hard time...

Ok hooked up a signal and the left rear channel is lower than the right rear on the scope. So I hooked up speakers and yep, way lower on left channel . I'll work on it more tomorrow, it's late here and off to bed. I'll need to trace the signal from input to output on the schematic. But Im...

Why not move the Zeners to the underside , keep them a little above the board. Then you'll have enough room for the 10uf Wima's . Athanasios

I got it !! I think I was way off on the trimpot setting for the one channel. I was not getting a reading at TR515 emitter , SO I probed the legs of TR 512 and 511 . E and B were both 0 but the C of 512 was 200mV higher than the C of 511 , So I left the probe connected to the collector of 511...

Well I discovered I did not have the 46 volts right at one of the 1 amp fuses. It was open. now it measures 49 volts ( I have 125 volt mains here ) So I installed a new fuse thinking that would solve the missing 25mV on TR515 emitter but no luck. Although the voltage went up on the C533 test...

Ok here she is all put back together . Passed the DBT and powered up on mains with no smoke :D All the B+ voltages are there the , 30,23 and 24 were all pretty close. But on the E of TR515 I am suppose to get 25mv and it should adjust via VR 501. In the SM you have to go back and forth...

I matched up transistors from the previous repair tech where they just changed one side . At Tr 511 they had a 2SA683 for a 2SA561Y I used two 2SA733's . Also TR510 had a 2SC828 for the 2SC734 that should have been there. I replaced TR509 and 510 with KSC1845's All the 2SC458's were replaced...

Change the relay. I bet its that . Had same issue with a Yamaha A-1 . Nashou

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You remove the jumpers on the back of the A7 shown here going from the pre out to main in Then I would use these splitters plugged into the Pre out on the A-7 then use a very short RCA to connect one of the right outs from the above splitter to the right Main in and the same for the...

I bought a bunch of SUPEX AL-2 tonearm lifter . Some times they come up on the bay . Nashou

Id do as Pete says , leave the original circuit as is. You mention a lamp? Never use a Dim Bulb tester on a V-fet with them installed . Athanasios

Those are MT-200 parts. Most are no longer made. I could not find a 2SD945 but there is a 2SD845 . The green one is most likely a 2SB755 . Athanasios

The A7 uses jumpers to take the pre amp signal to the amp section, so you would need a Y splitter to still send signal to the A7's amp section and the also to the Sub. The 717 most likely has the preamp to Amp section wired internally , where as no jumpers are needed. Athanasios

Got all caps replaced . Next is replacing the 2SC458LG's . I also found a few transistors that were changed out , so this was definitely repaired at some point . Most caps measured way over spec. All the 10uf caps measured 20uf + , 33uf caps measured 50uf+ , 100uf measured over 150+ . I never...

Well I looked for axials in the values I wanted and i just wasn't happy with what I found and I didn't need any another parts , so I decided to use some 470uf 50 volt caps I had and run them in parallel . So I used four of those and drilled holes in the PCB to feed the leads through and soldered...

ok this thread has me lost. Whats the point of this thread? Did the relay issue ever be resolved before going down the rabbit hole of PS noise?

Cleaned the bottom of the main board with some de greaser I use at work. Cleaned up nicely. Which also exposed the damage from the previous repair. Installed the heat sink and the KSD526's using Silpads and Shoulder washers with nuts and bolts. Yep, this is off a bit I'd say . I had...

I haven't looked at them yet , But they move nice and smooth . of all the gear I have worked on I never had a bad control pot, now trimpots are another story . Athanasios