Search This Blog

UHF Tools

[1] My Links


Wilkinson Coupler Calculator : Click

Noise Figure Measures -- 10 Tips from Keysight  Click

70 cm  Amateur Satellite List  Click

N6CA Website  Click

RF Tools [ Calculators ] Click

7 ways to create a quadrature 90 deg phase shift. Marki Tech Notes  Click

Shortcut to  Matjaž, S53MV links  Click

Generation of Low Phase Noise Microwave signals by dieter Scherer, 1981 [HP archive] Click

Coilcraft Inductor Chart [ 1008CS series (2520 metric) Ceramic Chip Inductors ] Click

... or these Coilcraft caps In size 0603  -- really great parts

Blank Smith Chart in pdf


[2] RF Bypass Capacitors for UHF

I swept some caps to identify what to use for RF bypass in my UHF circuits. Turns out, some of my stocked caps suffered poor attenuation at their series resonant frequency  (SRF). So I ordered some replacements. Any size above 0805 probably = a bad choice for UHF bypass. Above 1 GHz, then size 0603 seems prudent. I can't see, nor easily work with size 0402 and 0201 very well with my current lab gear.

Recall, we often build filter networks such as a pi networks made from arranged C-R-C or C-L-C parts, so choosing a cap with a SRF above your target ultra high frequency often proves wise.

The sweeps below show the SRF for various capacitors in my collection. Use as a rough guide --- it's better to sweep any particular caps from your lab to ensure their SRF and suitability.