Here is a substitute for a part made from unobtanium. The power switch used in the Heathkit SB220 was made by a company called "McGill".
Was.
Not made any more.
A bummer if yours goes bad. For years we would fabricate a metal plate to mount in its place, with a 1/2-in hole to mount a conventional 20-Amp toggle switch. Not refined, but functional.
Stumbled across a batch of McGill switches that almost fit. Rating is the same, 20 Amps at 277 Volts AC. But the mounting ears don't match.
Rather than try to bend the straight mount ears to match the original, we use a threaded spacer to mount the new one.
Oh,and the plastic rocker is half the width of the original.
The mounting hole centers also don't match, but the Whitney punch and a template make quick work of that.
The spacer we had on hand is threaded, and requires a flat washer between it and the inside of the front panel. Prevents the sloped shoulder of the flat-head screw from jamming the spacer's thread.
I'm just fanatical enough about lockwashers to recognize that they are missing from a lot of Heathkit amplifiers. Besides, they get lost when you take them loose. To replace this switch you have to remove the three big knobs, the half-inch nut on the band selector bushing and a 6-32 screw at each corner. This is my solution to missing lockwashers.
Once it's in place, moving the wires from the old switch to the new one should be done one wire at a time. Then again, if you got this far you would probably already know to do it that way.
Yes, it will look a bit lame when you're done, but it's a lot less work that taking the old switch apart and trying to rebuild it.
You have probably already guessed that this is a fleabay sale item in the making. It will get posted there for sale once we have enough of them modified and packaged ready to ship.
Time will tell.
73
Was.
Not made any more.
A bummer if yours goes bad. For years we would fabricate a metal plate to mount in its place, with a 1/2-in hole to mount a conventional 20-Amp toggle switch. Not refined, but functional.
Stumbled across a batch of McGill switches that almost fit. Rating is the same, 20 Amps at 277 Volts AC. But the mounting ears don't match.
Rather than try to bend the straight mount ears to match the original, we use a threaded spacer to mount the new one.
Oh,and the plastic rocker is half the width of the original.
The mounting hole centers also don't match, but the Whitney punch and a template make quick work of that.
The spacer we had on hand is threaded, and requires a flat washer between it and the inside of the front panel. Prevents the sloped shoulder of the flat-head screw from jamming the spacer's thread.
I'm just fanatical enough about lockwashers to recognize that they are missing from a lot of Heathkit amplifiers. Besides, they get lost when you take them loose. To replace this switch you have to remove the three big knobs, the half-inch nut on the band selector bushing and a 6-32 screw at each corner. This is my solution to missing lockwashers.
Once it's in place, moving the wires from the old switch to the new one should be done one wire at a time. Then again, if you got this far you would probably already know to do it that way.
Yes, it will look a bit lame when you're done, but it's a lot less work that taking the old switch apart and trying to rebuild it.
You have probably already guessed that this is a fleabay sale item in the making. It will get posted there for sale once we have enough of them modified and packaged ready to ship.
Time will tell.
73
