How to disconnect the dome wires on a Hammond CV preamp

[glensound]

I am pulling the preamp from my CV out for service and I don't quite know how to disconnect the wires from the metal dome tube. There are two large black wires going into this metal housing and I don't want to damage them. Please let me know, if you have done this before on a CV preamp.

[enor]

They are screwed in place. Each wire has a screw that holds its shield to the "dome", as you call it, and another screw holding the wire to its terminal on the phenolic circuit board. Pop off the lid and take out the tube for access (there are drilled holes in the "dome" for you to put the screwdriver thru).

[David Anderson]

Also, you only have to loosen the screws on the cable ground fittings to remove the cables. You do not have to remove the screws completely. The metal fittings should slide out once the screws are loosened. As enor says, you have to remove the 6J7 tube first.

Take note (and preferably photos) of how all wiring is arranged prior to disconnection.

Don't feel bad about asking. This is not an obvious procedure if you haven't done it before.

[glensound]

Thanks! I have pulled the preamp out without damaging anything. One thing that puzzles me is the small screw on the right side of the dome that I removed to do what I thought was holding the top to the bottom. After pulling the preamp, I cannot see any hole where this screw was located. Any ideas? What am I missing here?

[enor]

Thanks! I have pulled the preamp out without damaging anything. One thing that puzzles me is the small screw on the right side of the dome that I removed to do what I thought was holding the top to the bottom. After pulling the preamp, I cannot see any hole where this screw was located. Any ideas? What am I missing here?

There's a bunch of screws that hold capacitor clamps inside the preamp. Are you talking about one of those screws?

[glensound]

No, This was a screw that I thought was holding the dome tube cover on the right side towards the back (the cover that you pop off to pull/replace the tube). It was on the skrit part of the top dome cover. Not that important in the long run since the dome seems to fit snug.

[enor]

There's no such screw on the -V amp in my AV; and I don't recall having one on my previous CV either...

[glensound]

I finally got my CV preamp back from the shop...

Can someone please verify for me that the 2 wires inside the large black wires to the dome are screwed together on the card inside the dome? I think they originate at the vibrato scanner.