When I built the first prototype of the iPhone DC receiver, I just reached into my junk box and used a polyvaricon capacitor for the main tuning control. It was marked PL 051. I was really pleasantly suprised at the stability of the Variable Ceramic Oscillator circuit. I could tune the entire 40 meter band with complete stability -- Juliano levels of stability.
Has anyone else noticed variations like this in the stabilty of polyvaricons?
The dial in this version is an Archer device that has been kicking around in my junkbox for more than 20 years. I think it was given to me by my old friend Pericles HI8P -- this adds a tremendous amount of soul to this new machine). The box is an old Bud aluminum chassis. Man, this thing sounds great. I will try to post a video soon.
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I have a varicon(whether poly?) as used in SONY ICF-sw-11that was made in Japan (not China)and when i had minor issues with it and removed for cleaning up,
ReplyDeleteit has proved to be made from PTFE
I was happy.
The logic "not all polyvaricons are same"Stands well.
73s
sarma
vu3zmv
Bill
ReplyDeleteI noticed that nice looking HP8640 signal generator on the bench, but I seldom see sensitivity results for your receiver designs. How xbout it? While you're at it, how about some RF overload data for the mixer we've been discussing off line?
Joe
W3JDR