Crystal Radios Of The 2004 Contest Entrants
Here is a picture of Dan's set, the "Litz Blitz". This set is in the XSS Newsletter as an article in the March, 2004 issue.
Notice the FT114-61 cores and large diameter wire. Brian uses separate cores for Lo Band/Hi band.
Steve uses a BC-221 as the basis for his BCB set. The BC-221 is a frequency meter, WWII vintage.
Mike Tuggle's record smashing DX set.
The matching unit.
I started putting the set together on January 5, 2004...way late! I used a black plastic clipboard for the front and a clear orange plastic one for the chassis plate. 1"x3" small boards are used to hold up the chassis plate. I installed the coil supports during the contest and the phone jack afterward.
This set is a modified bandpass unit, but uses two separate coil assemblies. Each assembly consists of toroids wound on FT114-61A cores for the antenna and detector coils. Each assembly has it own coupling coil, connecting the antenna and detector circuits.
Here are the specs:
Antenna: FT114A-61, 33T #18
Couping Coil:FT-82-61, 10T ant side, 5T detector side, tapped every turn (det side only) Detector: FT114A-61, 40T #18
Antenna: FT114A-61, 22T #14 Couping Coil:FT-82-61, 10T ant side, 5T detector side, tapped every turn (det side only) Detector: FT114A-61, 20T #14
The audio transformer is one of the Fair Radio 100k:100 ohm units. The headphones are Dynalec mic elements. I started with one of the ITT diodes, then settled on one with a blue stripe (characteristics unknown).