Re: [Amps] placement of RF choke bypass cap.

["pc5m, Carel" <pc5m@xs4all.nl>]

Did a small experiment:

See www.pc5m.com/skineffect1.jpg

- Groundplane with BNC connector and wire on top to ground
- Connect sweep RF generator and spectrumanalzer parallel at BNC
- At half wave resonant freq I would expect a short (and a dip in swept
measurement)

1. Just the wire, total length 33 cm (12"):  resonance/dip measured at 380
MHz 
2. Put a full circular metal disk in between (r= 5cm [2"]): resonance/dip
measured at 260MHz
(lowest point of disc about 1 inch above groundplane)

I think this will proof that RF does NOT go through the metal .....

Gl, Carel.

n.b. 
33 cm =  1/2 wave at 440MHz (measured 380 due to velocity factor of 0.8)
33 cm + 10 cm = 43cm = 1/2 wave at 350 MHz. 340 * 0.8 = 280 MHz


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