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40-180 Questions
#1

I began my first restoration project a few weeks ago and have recapped it, replaced most of the resistors and completely rewired it. I brought the input voltage up slowly with just the 84 tube and was happy to see I hadn't done anything catastrophically wrong!

With all the tubes in place all filaments are glowing nicely, B+ seems a little high at 205V and a few random checks at plates and screens seem reasonable.

I am getting dead silence from the speaker however. The field coil is good at 1105 ohms and I am confident the field coil is wired correctly at the + side of C58 and C61. I also double checked the audio transformer primary wiring against the schematic and it's good. There are no other transformer wires and no sign of any other wires that may have been cut. I think I'm missing a secondary winding wire.

The speaker voice coil wiring makes no sense to me. I rewired it exactly how I found it. The chassis however was in suspect condition when I started. For example, there was no connection at the 84 cathode! One voice coil wire is connected to the audio transformer ground strap and the other is wired straight to ground.

Assuming I need a new audio transformer, I also need the correct connections for the speaker voice coil.

Can anyone point me in the right direction for a replacement transformer and the correct wiring?

Thanks much.

Gary


Messages In This Thread
40-180 Questions - by GaryM - 07-22-2012, 03:07 PM
RE: 40-180 Questions - by 7estatdef - 07-22-2012, 06:36 PM
RE: 40-180 Questions - by GaryM - 07-22-2012, 07:34 PM
RE: 40-180 Questions - by 7estatdef - 07-22-2012, 08:35 PM
RE: 40-180 Questions - by GaryM - 07-22-2012, 10:34 PM
RE: 40-180 Questions - by gary rabbitt - 08-01-2012, 09:34 PM



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