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Author Topic: "New" 1920's Crystal Set Build Started  (Read 133 times)

Offline NQC

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"New" 1920's Crystal Set Build Started
« on: May 31, 2021, 2331 UTC »
Hey All,
 
I recently picked up a beautiful 1920's variable cap mounted in a heavy oak side sloped enclosure. The cap , dial and panel look almost like new.

The downside was that it  only topped out at 250 Pf , not really high enough for any of    my "serious" uses. The  inductor for the bottom of B'cast  is 400 uH (!) of #28 rectangular five point spiderweb.It looks more like a SAILBOAT than a spider's web :). Space was extremely tight. It's  wound   on a small sheet of vanished writing pad  thin  cardboard. Basically I "tried" to violate EVERY rule of good crystal set building (re L/C ratio, coil shape,  coil form material ,  var cap insulation being  bakelite, etc, etc).

I may try a few outboard tricks to "sort of" help it, but don't expect too much other than locals here.

But it WILL be a NICE piece of "eye candy" with nickel binding posts, cotton wire, etc ,etc. Everything is being  done with  1920's material and look.

My bedside shelving is small and already mostly packed up with gear , but this rig will be small   and should fit .  I'm thinking of a  fun little single dial radio for the local  big guns on an indoor short wire, which is fine.

Years ago I smelted my own "home brew" lead  sulphide material by melting lead and rapidly working in  raw sulfur. It  instantly burst into flames and had to be blown out like a big birthday candle.The  resulting material was black and ugly- NOT pretty and  sparkly like   the silver bearing "steel" galena " that I've also  used   . But BOY, was it HOT- very sensitive and easy to set . Maybe I try  whipping up another   batch  in a small metal cup  for use on this set.

K
« Last Edit: May 31, 2021, 2350 UTC by NQC »
Station main receiver : Bed springs to  blue razor blade detector to 2000 ohm cans to steam  radiator. Grid FN 42