"Scott Dorsey" wrote in message
...
Antonio Vernucci wrote:
Can any one explain the rationale behind using both octal and loctal tubes
in
the SX-42?

Loctal tubes were really cheap on the surplus market at the time?

I believe the lone Loctal tube was a 7F8; at least this the tube used in my
SX-43. If you want to read more about this particular tube, check out the
volume on components from the MIT Radiation Laboratory series. If memory
serves, this dual triode was rated to much higher frequencies than any dual
triode that had an octal base. These tubes are still available NOS.
However, if you are willing to make an adapter or rewire the receiver, I
believe a 12AT7 can be used. Of course, if you want "museum quality", which
I think is rather foolish, use the 7F8.

73, Dr. Barry L. Ornitz WA4VZQ