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Eico HF-81 rebuild: follow-up

Replacing the on/off switch is easy if you install a new switch on the rear panel. The AC switch mounted on the back of the pot is problematic and can result in noise added into the audio signal. Technically, having an AC source so close to your signal processors is not an ideal situation. Since this amp is one for your collection you can easily relocate the power switch to the back panel. Get a slide switch which mounts in the convenience AC outlet. (These AC outlets can be disabled if you don't use them as they are also a source of AC hum. Also they are dangerous and not up to electric code since the prongs from a power cord can easily short out on the chassis if the plastic body is broken).
In some of my vintage amps relocating the on/off switch and removing the AC outlets reduced the noise floor in the amps.
 
my on/off switch has ALREADY been relocated to the unneeded "TAPE" speed switch on the front panel

I'm wondering now just how to REMOVE the old on/off switch that is still stuck piggybacked to the back of my treble pot... I think that it's mechanically interfering with the range of treble pot rotation (something must have broken inside, and it no longer even clicks on/off)

can I somehow pry it off of the rear treble pot?.. do I have to cut something first?

if could have the assembly out in my hand I could probably figure this out, but I don't want to damage the treble pot(s) during removal

I am hoping to avoid having to completely de-solder the entire assembly and remove it from from my amp... lots of extra work!

hoping to be able to remove the power switch with the treble assembly in place

thanks everyone!
 
You have nothing to lose removing the pot and trying to pry the switch section with a screwdriver maybe. Be sure to have an available replacement though. If I remember well, there is a center lug or tap on this one.

Good luck!
 
RE: "Be sure to have an available replacement though....."

don't have a spare one now, and not likely to ever find one of these in good working order
 
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ssouci said:
RE: "Be sure to have an available replacement though....."

don't have a spare one now, and not likely to ever find one of these in good working order
Click to expand...
You can get an Alps of the 500k or 250k variety, also Noble, which work and sound better than the old worn out VC. It is amazing how much smoother those work than the originals. You might have to cut the shaft to get it to the same length as the original VC. I mean if you are going to take out the original you might as well replace it since there is no guarantee that what you do will fix it. And for all the hassle of desoldering and resoldering or putting in new wiring, you might as well replace it.
 
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