Supro with 6L6's? (and grounding ?)

[Jonny toetags]

Hi guys,

My buddy bought this Supro online and went ahead and bought some new 6973 powertubes for it (thinking it was a 24)
I've never seen a Supro with 6L6's...what model is this?
He is basically looking for that Supro breakeup, but it's not happening right now with these tubes in it. What do you suggest?
Also, I have to install a grounded powercord. Can I ground this the same way I do on Fenders (minus the standby switch)?

[EFK]

Valco made quite a few models with 6L6, I'm not a fan of most of them. That there is a model 6497. Installing a grounded cord is installing a grounded cord, however on this you need to adjust some of the wiring up at the switch in the top chassis. You want the AC line going into the lower chassis, up the connecting cable, directly to the fuse, then the switch, then back down the connecting cable to the PT primary. The AC neutral should just go right to the other PT primary in the lower chassis and of the course the AC ground should be bolted to the lower chassis where it enters. As you've probably figured out, the standby position on this has nothing to do with the power but is just a mute switch that brings the power tube grids together to cut off the sound.

[Jonny toetags]

Thanks for the info EFK.
I've done the ground plug on many Fenders and a few Ampegs...but this is my first Supro.
Such an odd design with the connecting cable.
If I run into a snag, expect an email

Valco made quite a few models with 6L6, I'm not a fan of most of them. That there is a model 6497. Installing a grounded cord is installing a grounded cord, however on this you need to adjust some of the wiring up at the switch in the top chassis. You want the AC line going into the lower chassis, up the connecting cable, directly to the fuse, then the switch, then back down the connecting cable to the PT primary. The AC neutral should just go right to the other PT primary in the lower chassis and of the course the AC ground should be bolted to the lower chassis where it enters. As you've probably figured out, the standby position on this has nothing to do with the power but is just a mute switch that brings the power tube grids together to cut off the sound.

[Jonny toetags]

Couldn't I just add the new power cable where the old one is, wire the green to a ground tab and remove what I think is the 'death cap' (circled in red)?
Here are a couple pics.
Up top:


Down low:


If I really do have to bring the line in the bottom...might need a little guidance with the wiring. I'm not used to working with a 'connecting cable'.

[EFK]

Oh I see, yes, just replace what's there with the new cable. I was thinking of the older amps like the Brentwood etc. (I've been working on one lately so I have it on the brain!) where the power cable comes in through the lower chassis and the hot is run through the connecting cable up to the fuse and switch and then back down again. These are different and a better arrangement - just make sure that the proper type of fusing/switch arrangement is present, i.e. the line (hot) should run to the fuse, then the switch, and then down to the PT, and the neutral should run only to the connecting cable and thence down to the PT directly. And yes, definitely remove the polarity cap circled as it will no longer serve any purpose.