[Amps] plate bypass capacitor

[Gary Schafer]

> -----Original Message-----
> From: amps-bounces at contesting.com [mailto:amps-bounces at contesting.com] On
> Behalf Of Bill, W6WRT
> Sent: Saturday, August 08, 2009 11:30 PM
> To: amps at contesting.com
> Subject: Re: [Amps] plate bypass capacitor
> 
> ORIGINAL MESSAGE:
> 
> On Sat, 8 Aug 2009 22:59:20 -0500, "Gary Schafer"
> <garyschafer at comcast.net>
> wrote:
> 
> >
> >What happens on 160 meters and even 80 meters with a choke that is "too
> >small" for the frequency involved is that it is operated in a parallel
> >resonant mode with the plate tuning capacitor in order to provide a high
> >enough impedance.
> 
> REPLY:
> 
> A "too small" choke is indeed in parallel with the tune cap, but it had
> better
> not be *resonant* with it or fireworks will follow. The relatively low
> reactance
> of the "too small" choke is compensated by increasing the value of the
> tune
> capacitor, but that is not resonance, just the normal way opposite
> reactances in
> parallel combine in a non-resonant manner.
> 
> Resonance is where XsubL = XsubC, and that is not the case here, far from
> it.
> 
> 73, Bill W6WRT
> _______________________________________________

Bill,

"Normal way opposite reactances in parallel combine in a non-resonant
manner"? what does that mean?

Calculate 100 microhenries in parallel with a 75 pf capacitor. I think that
you will find it to be resonant at around 1.8 MHz.

Why would you think that the choke can not be operated in a parallel
resonant mode? It is no different than placing any other inductor of proper
value in its place and tuning it to resonance.

73
Gary  K4FMX