My 5e3 wiring thread... Need all the help I can get

[cdc3jj]

So my cab in almost done, and my kit from ceriatone is here. Board is finished, everything else is up to me. Is there a trick to attaching the board to the chassis? Is it easier to install pots, switches and sockets before soldering? And is there somewhere that explains all the wires off the PT? I got merc trannies and the color scheme looks different from nik's (ceriatone) layout. Here's where I am thus far...

Staining the cab tomorrow. Salvaged the grill cloth from a 70's hammond organ.

Thanks in advance.

[tube.tone]

What is your PT model?
Usualy, red leads go to pin 4 and 5, yellow leads go to pin 2 and 8. Green and yellow and red and yellow go together to ground. Green leads go to the pilot light and then to filaments. Black leads, one is the to conect to the outlet phase and the other one is the neutral.

I hope this helps.

[tubeswell]

Originally Posted by tube.tone

Usualy, red leads go to pin 4 and 5,

I think you mean 4 and 6 don't you?

[tube.tone]

Originally Posted by tubeswell

I think you mean 4 and 6 don't you?

Yes, Thanks tubeswell! Red leads go to 4 and 6.

Also, The transformer may have several taps on the primary in different colors. You'll have to select the correct for your wall voltage.

[Ricky D.]

I built a Mission 5E3 kit, which is that much experience... Anyway, here's a few things that could make it easier.

Use the brass plate as an assembly fixture. Mount your pots and jacks on the plate. You can then wire them on your bench instead of inside the chassis. Then take off the nuts and gently mount the whole subassembly in the chassis in one shot.

Mount all the tube sockets and transformers in the chassis first. If your kit didn't make provision for mounting the board, figure that out before you go any farther. If it was mine, and I discovered at this point that I had to drill holes in the chassis, I would first do the layout (mark the holes), then disassemble the chassis. This would be to ensure that all of the metal chips get cleaned out.

Anyway, wire the heaters on the tube sockets first. The heaters need to be twisted together as much as possible. Some people float the heater wires an inch or so above the sockets, which looks trick. On advice, I brought mine down to the chassis, then across to the lip at the edge of the chassis opening. Tucked under the lip, they are absolutely out of the way as things get more crowded around the sockets.

Check your wiring on the board several times before mounting it in the chassis. Double super extra check the wiring under the board, you don't want to have to pull the board to fix a blunder.

Good luck, and don't be shy about asking questions. We love this stuff.

[cdc3jj]

Thanks for the tip on the brass plate... I have a weber PT and a merc OT. Got the first few tube connections wired and had another little project come up. I'm going to wire the trannies in tonight and place the board. I might go ahead with the board wiring or I might wait. Depends on how my attention span holds out.

[tubeswell]

If you are still at the stage of being about to wire the PT in, then you might want to add a 1000V 1A diode in series with each side of the HT winding and the respective rectifier anode(s), with the banded end (cathode) of each diode pointing towards the respective rectifier anode. (Schematic attached)

This protects the PT HT winding if your rectifier tube shorts, by preventing Hi-voltage AC destroying your filter caps (if the rectifier shorts) and thence shorting the HT to ground. They won't affect the operation of the rectifier tube at all, and in fact act as a back-up SS rectifier if the rectifier tube shorts (albeit that your B+ voltage will be higher if this happens). R.G. Keen mentions this in his immortal amp mod series of articles. It is cheap to do and worthwhile.

[Groovey Records]

Not that we are not willing to help but doesn't ceriatone offer step by step instruction like Allen or Metropolus ??

They offer email tech help colored diagram and metro has their own forums

I never did a ceriatone kit because I support made in america companies but surely they offer some guidance?