Trouble matching SA605 input at 434 MHz
I am having trouble matching to the input of a SA605 at 434 MHz.
If I apply a sig gen directly to pin 1 via a 1n cap I get around - 95Bm
sensitivity. I then add my match and the sensitivity drops more than
10dB. I am expecting 10dB increase in sensitivity when input is matched
correctly.
First I tried matching to 800R as per input impedance listed in the
Philips APP note. I then noticed most applications matched to 1k5.
My current circuit is C-Tap (33pF to ground and series 5p6 to inductor).
18.5nH inductor (Q = 100) across input pins 1 and 2.
10n decoupling cap from pin 2 to ground.
Any help much appreciated.
Regards
David
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