Answering Robb's question made me think of a very mild puzzler:

Can you think of a way to connect up an octal tube socket so that no
matter what orientation a pair of crystals is put into it you'll still
have two switchable crystals (no forcing pins allowed -- only schemes
where the crystal goes into receptacle 1 & 3, 2 & 4, etc.).

And, after you exercise the dozen brain cells that it takes to answer
that question -- did anyone do it in a production radio, or publish it in
a magazine, that you know of?

--
My liberal friends think I'm a conservative kook.
My conservative friends think I'm a liberal kook.
Why am I not happy that they have found common ground?

Tim Wescott, Communications, Control, Circuits & Software
http://www.wescottdesign.com

On Wed, 30 May 2012, Tim Wescott wrote:

Answering Robb's question made me think of a very mild puzzler:

Can you think of a way to connect up an octal tube socket so that no
matter what orientation a pair of crystals is put into it you'll still
have two switchable crystals (no forcing pins allowed -- only schemes
where the crystal goes into receptacle 1 & 3, 2 & 4, etc.).

And, after you exercise the dozen brain cells that it takes to answer
that question -- did anyone do it in a production radio, or publish it in
a magazine, that you know of?

I don't know, but it seems like the sort of thing you'd find in a Hints &
Kinks in QST, or filler in CQ (they had a book issued in the fifties that
collected little bits, I can almost picture almost picture something like
this in there).

Michael VE2BVW

Hallicrafters did it on the SX-25 only they blocked out two of the holes to
make the hop-scotch wiring work. The problem you run into is the holes near
the key, so I would suggest filling them to make them unusable.

Hi OM Tim,

I have done it only for 1 FT-243 crystal, pluggable any which way in an octal socket but still getting connected.

It's built into a Quartz Crystal Tester I homebrewed.

Here's the link.

http://nandustips.blogspot.in/2012/0...al-tester.html

73

Nandu.

Hi OM Tim,

Here's my solution.

Don't think it was published earlier!

73,

Nandu.