[Amps] National R-175 Choke

[RFlabnotes at aol.com]

Recently someone posted a request for help on analyzing this famous plate 
choke for possible resonances, but I can't find the original post (I don't 
keep old mail for long). This morning, I found one of these things hiding in 
a box of parts that had slipped below the radar. I pulled it out and did a 
quick sweep with the Vector Z meter, so if whoever that was will contact me, 
I can email you all of the resonance data.

They made both an R-175 and an R-175A - I don't know which we have, but it is 
pristine so whatever you have, you can compare it with my physical 
measurments to verify.

73
Eric K8LV