[ARC5] Bypass Cap Question
Mark K3MSB
mark.k3msb at gmail.com
Sun Nov 24 23:01:01 EST 2013
Hi Guys --
Getting back to work on my SCR-274N issues, namely the nasty buzz on 40M as
related in previous posts a few months ago.
I haven't had time to do much work on this since then as life has gotten in
the way. Our first son has left the nest and is in basic training at Ft
Sill in Oklahoma; this was a big "event" for Barb and I to deal with as
you probably can well imagine.
It was suggested to me that I bypass all the power leads with a 0.01 uF cap.
Now, we all know that Xc = 1 / ( 2 * PI * F * C). Since my power
supply has about 100 uF in the filter stage, the capacitive reactance to
ground will be
1 / (2 * PI * F * 100).
This is less than 1 / (2 * PI * F * 0.01) which is what the 0.01 cap will
provide.
So, what's the point in adding the 0.01 uF caps to each of the power leads,
since I derive them all from a common line (using the classic divider for
the transmitter) and there already is 100 uF between the 550V line and
ground?
73 Mark K3MSB
More information about the ARC5
mailing list