Are these VD1212 replacements installed correctly?

I recapped my C-4 and while in there, I'm replacing the VD1212s with a series pair of 1N4148s.

I lost track of one VD1212 on removal looking for the dot. Unfortunately, this is one of two locations that does not have the component labeled on the board. The available board views in the SM are not as legible as needed.

I did my research and checked that the outside of each VD1212, that is not marked on the board, goes through a resistor to the same buss, one on each side of the board. So I put the unknown unit in the same way wrt this buss as the other diode.

Can someone confirm that this replacement diode is in the correct orientation? The diodes are installed with the cathode to the inside, middle of the unit. It is the one on the right in the picture.

Can someone confirm that this replacement diode is in the correct orientation? The diodes are installed with the cathode to the inside, middle of the unit. It is the one on the right in the picture.

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All 4 cathodes should all point to the center of the board.

Thanks Dave,

I knew you had the answer right there as in some threads on the C4 you mention you have done quite a few of them.

All four are cathode to the center and it wasn't until late that I even found the one under the switch actuating cable. Another one was hiding under the aluminum arm on the front board. Think I have em all, nine so far. Still looking before I reassemble. Solder joints are part of this inspection.

It's been awhile since I did my C4 but there is one that looks like it can be a VD1212 but is not. If you change that one it won't work. Dave will know better which one it is. :scratch2:

The 9 double diodes I replaced were the 4 on the back board that Avionic mentioned above, the two on the headphone board, the two kind of under the middle aluminum knob extension and the one over by the ±30 adjustment pot.

All were marked as double diodes except the two to the left side of the back board shown in the picture in the first post. There were indicated by a jumper on the board but they were diodes.

I sure hope I don't swap in too much stuff and the unit works just fine when I get it back together.

When I was recapping my C4 I remember reading a thread on someone changing out one that wasn't one. 9 of them seems right but like I said it's been awhile since my recap. Dave does them all the time so he will know for sure and he probably remembers the thread on it.

Well it works, at least after I moved the balance control to allow both channels to play through a test rig.

Now to let it burn in for a while and then see about those offsets that were way off and now very touchy with a 12 turn pot. Got the 30 volt right on the money with the original single turn pot. Fancy new stuff is making offset a bit difficult. Well see what happens tonight.

The offset is still touchy, jumping all the time but I did get it dialed into about <50mV. A slight touch of the pot in either direction can make the offset jump over ±200 so I stopped when it was under fifty since the spec is under ±200. done. Listen to it for sonics tomorrow I guess. All you guys loving this preamp, hope you are right.

This unit sounds good. Sure doesn't hurt to have Steve's hi-buck cartridge feeding the MC input. Had a hum on CD on first play in the main rig but a change of interconnects fixed that just fine.

Need to install a high output cartridge in a tt to test the other two phono inputs. But the Tuner and Aux sound great as well as the Tape input for the CD changer.