[GreenKeys] Model 15 chassis voltage?

[George B. Hutchison]

GreenKeyers - - -

R.F. interference can be a serious business, but having your 
pacemaker fried in your chest is ALSO serious business.

As pointed out earlier in this thread, the old teletype filters are 
just that, old.

I believe that the Teletype theory of RF interference treatment was 
done in a "one size fits all" mind set, and thus every keyboard had 
filters, every base likewise.

It must be considered that early equipment, particularly WW II 
vintage stuff, had the possibility of being powered by everything 
from diesel gen sets, waterwheels in remote country settings, or 
maybe even a donkey running in circles with a tough jungle vine 
threaded through a pulley affixed to an ancient washing machine 
motor wired as a generator. The line filters on teletype stuff, 
particularly with governed motors, had a big chore to do.

I have one outlet set in my shop that is fed from the breaker to 
both a non-GFCI outlet and a GFCI in the same box.  An old radio 
will trip a GFCI as you plug it in, and since all of the test gear 
on my bench is powered through that GFCI, the second outlet was 
imperative, and even then it is not unusual for everything to be 
running well until you clip your scope ground to the device you wish 
to look at. The sudden silence accompanying the click of the 
tripping GFCI is very loud!

The isolation transformer is very good, but can be costly.

Mr. Angus hits it just right. New, smaller components is the ticket.

Sadly, he actually got his last line somewhat wrong. It should read:

ABSOLUTELY NO WAY WOULD I RUN ANY EQUIPMENT UNGROUNDED!!! (Caps)

W7TTY