Re: wooden radios & carpet tacks

---------

From: Randy (randy@cyphyn.radnet.com)
Date: Mon Nov 22 1993 - 14:39:56 EST


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
grey-brown...
 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!"
randy@192.153.4.200             DON'T  JUMP!                     -Peter Keyes
                     You might break an expensive tube!


Search QRP-L Archives

[ QRP-L Archive | ]
[ 1993 | 1994 | 1995 | 1996 | 1997 | 1998 | 1999 | 2000 ]

---------

This archive was generated by hypermail 2b29 on Fri Jun 02 2000 - 11:26:21 EDT

kd4ab@kd4ab.org