From: Randy (email@example.com)
You HAVE been peeping over my shoulder!
Paper clips for connectors to a 6v lantern battery....well, in MY case,
as the jumper to connect one to the other, for 12 volts....
Stain-to-go-with-tacks... Oh my!..The boards I used , were old,
weathered, a bit warped siding-wood (?) from a torn down garage...sorta
Ya know.... they MAKE a 'stain' like that!
Actually, a well dried board ( from pine to plywood) , while still hot,
then varnish-dunked (or quickly spread it on) so to take place of any
moisture and seal out any, later...is best.
I used to snitch some of my mothers canning wax ( paraffin...large blocks)
and melt that into the wood....my gawd how much wax it would absorb.
This made it so the wood would not act as a resistor and send B+ into
a 1st grid...
Somthing like that once happened---drove me crazy as to why the tube kept
glowing red ( plate) in spite of my increasing kathode resistor values.
( This was a #42 pentode tube...was using as audio amp )
Thought the tube was sour, which meant a long walk to the local
TV and Radio store down town to get it tested...it came out as OK, and so
back home I would trudge , happy the tube was ok, and then..
I'd push it back in the board, and it would over-conduct again....
It took me 3 trips down town, before the guy asked what I was doing...
I explained, and he then realized what must be occuring:
The screen volts (+) was 'leaking ' thru the wood to the 1st grid.
Now ya can't get paraffin...so I use varnish...which is also getting hard
to get...what with all these edible latex 'paints' in vogue now...
I wonder if Wesson oil.......
-- Randy KA1UNW If you get a shock while servicing your equipment, "Works for me!" firstname.lastname@example.org DON'T JUMP! -Peter Keyes You might break an expensive tube!
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