Thanks for the information Stew. Originally I tried it at my parents QTH on 40
meters when I was teenager. Was licensed in 1950 as W1TJQ.
Ideas get lost and time goes by. In the 1920 Hugo Ginsburg ( not sure of his
last name spelling) in a book at the Belfast Library said silicon looked
promising as a rectifier. It took to early 1950/ late 1940's for it to be
re-discovered.
Thanks again.
73
Bruce-k1fz
On Fri, 23 Dec 2016 01:51:50 +0000 (UTC), GALE STEWARD via Topband wrote:
Years ago at the W3GM M/M station, Gerry had several crystal filters (50
ohm Z input & output) in the 40M RX path. As I recall, these were about 20-30
khz wide (each) and were of slightly different center frequencies so that most
of the 40M CW band could be covered.
I DO remember that they worked very well. I never saw one for 160.
73, Stew K3ND
From: K1FZ-Bruce
To: Topband
Sent: Thursday, December 22, 2016 3:41 PM
Subject: Topband: "Thinking out loud"
We know that limiting the noise pick up from more directions of an antenna we
can usually hear better. We also know if we limit the noise from a receiver IF
we can hear less noise, and better yet, if we
have a roofing filter earlier in the receiver we can eliminate even more noise
in relationship to the wanted signals.
What if we take it a step further, could we limit the band-with of the antenna
signal with a crystal lattice for 160 meters before the receiver.
Years ago I played around with a single crystal at the input of an old tube
type receiver. It was remarkable what I could hear on 40 meters, on what seemed
to be one frequency.
73
Bruce-k1fz
http://www.qsl.net/k1fz/beverage_antenna.html
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