Crystal-Set Performance Comparison
- Whenever someone writes up a description of a crystal set they tend to represent it as "the greatest thing since sliced bread." However, there is a vast difference in the performance of different circuit topologies. My intention here is to show a comparison of some representative crystal sets so the prospective builder can make a wise choice.
This is "City Mouse" territory. I'm in Jersey City, New Jersey about 4 miles west of Downtown Manhattan. There are a lot of stations within 10 miles. DX listening is just about impossible here as my sets can't summon up enough selectivity to hear between the locals..
Day-time reception. Antenna is 50-ft wire just above the roof, at about 25 feet.
R = good reception.
R+ = extra loud
R- and R-- = weak or splattered by stronger stations.
WNYC is 10KW and only 2.5 miles away. Plus, their directional array is pointed directly at my house.
Philmore Super Radio Crystal Set
This is a typical cheap commercial crystal set. It heard 4 stations, only one really well. It would be severely challenged out in the country. This is the sort of radio that gives crystal sets a bad reputation. Don't waste you time on something like this.
Aeriola Junior Clone
My version of the Westinghouse crystal set from about 1921. The engineers knew enough to tap the detector down on the variable inductor, and provided a coupling cap to support long antennas,
AA5
Built from the wreckage of an "All-American Five" tube radio to show members of our antique radio club what they could do with parts from their junkbox.
My Living-Room Set
This is yet annother version my Pretty Good Crystal Set using a ferrite core inductor and an audio transformer to drive inexpensive esarbuds.
This is the sort of radio I recommend for beginners. It performs well, and the original PGXS with an air-core coil can be easily expanded tp a double-tuned set for high performance.
Here's a PGXS recently built by one of our club members:
From Jefferson, ME (Half-Way Down East) about 325 miles from NYC he logged: 880 WCBS, 1130 WBBR, and 1010 WINS in NYC, 1520 WWKB Buffalo NY, 180 WTIC Hartford CT, and 1210 WPHT in southern NJ. He was using a Nathaniel Baldwin headset.
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My Reference Set
This was the original prototype for my HP-002 High-Performance Crystal Set.
The numbers in the REF column are the DC voltages measured across the 100K diode-load resistor, and represent comparative signal strengths. I easily logged 19 day-time stations. Sound-power 'phone were used.
Here's a log from a few years back when I was still a "Country Mouse."
My radios were designed with reproducibility in mind. There are no really exotic components, with the possible exception of the audio transformers.
Here's my presentation on Building Homebrew Radios.