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Akai GX625 heads

I have a Akai GX625 and I need to replace the heads. Does anyone know where I can get them, how much they cost and how to install them?

NAD 312 (for my NAD 302) adjustments

Hello everyone. First I wanted to check if voltages and idle currents are correct and I got the following:

1. Offset voltage across E401 and ground was 0 volt left channel. Looked
ok so I did not bother to turn R411. The same for right channel E402,
0 volt with ground.
2. Idle current. My board didn’t show a LK 39 link but there was J436
wire jumper across R455 left channel. I disconnect the wire and
measure voltage across R455. Volts reading kept on changing between
0.02-0.04 volts. For right channel voltage across R456 also kept on
changing 0.02-0.04 volts also. Not sure if this is ok.
3. My original problem with right channel is still there. It works one
day and does not work the next. I think this is in the main section
because preamp both channels are working.
4. I am now using my NAD as a preamp only. Music is still good with my
DIY amp kit.
5. Thanks a lot!

PS. My board is 302 but 312 diagram is exact including the power supply and pre amp sections. The difference I found was in the values of transistors Q411-Q418 left and right channels. And of course J436, 437 for LK39 and LK1.

Errant's picture


This deck is actually an Akai GX-635D and is a 6 head auto reverse model. It plays in 2 directions. There is also a Dolby version. The Akai GX-625 is a 3 head model without auto reverse so you have to change the reels over to play side B.