ken scharf wrote:
HERE'S the link http://www.io.com/~nielw/3tubrcvr/3tubrcvr.htm
Oh, nearly forgot....
With a little head scratching, you can replace the 6K8 with a 6u8, 6ea8,
6x8 (etc) triode/pentode. Use the pentode as the mixer and the triode
as the oscillator. In many cases the inter-electrode capacitance inside
the tube will provide enough coupling from the oscillator to the mixer,
but you might need to use a gimick capacitor (twisted wires) from the
pentode grid to the oscillator plate. Other tricks are to connect the
pentode screen to the oscillator plate, or in the case of the 6x8, the
pentode grid 3 to the oscillator grid.

The 6c8 may be replaced by ANY dual triode (such as 12au7, 12at7, 12ax7,
6sn7,6sl7, etc....)

I think we may be in business, here. Went through my selection of
tubes, and there's a 6X8 and a 12AX7A among them. Three other tubes
looked like they had promise - two 12AV6 and a 6BU6.

After I'm done with this post, I'm going to Google Images to see if I
do indeed have 2000 ohm headphones. I want to make sure, because
elsewhere I found a crystal shortwave radio that uses them as well.
That might serve my needs better, although it won't have those cool
glow in the dark tubes.


Ralph