Hi At 1.5 GHz something like a 50 to 100 pf NPO is probably the best pick for a blocking cap.
Why? It does a fine job at the intended frequency. It acts as a high pass down lower where lightning energy is a bit higher …. Bob > On Apr 30, 2020, at 9:25 AM, Ben Hall <[email protected]> wrote: > > On 4/30/2020 7:33 AM, Bob kb8tq wrote: >> Pretty much all the Mini Circuits splitters will pass DC. > > Hi Bob and all, > > That's absolutely correct. Something you might consider is what I did - I > got a pair of Mini-Circuits ZC6PD-1900W's cheap on the e-place. > Frequency-wise and loss-wise, not perfect, but good enough for me. Problem > was, like you note, all the ports are DC-pass, and I wanted only output port > 1 to be supplying DC to the antenna. > > So I opened mine up, carefully cut the trace going to outputs 2 and up, and > bridged them with, IIRC, a 0.01uF ceramic capacitor to block DC. > > Before and after plots on the VNA at work showed very little increase in loss > after the mod compared to before the mod. > > Just some food for thought. :) > > thanks much and 73, > ben, kd5byb > > > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
