[Amps] Plate Choke Resonances

[Gary Schafer]

> -----Original Message-----
> From: amps-bounces at contesting.com [mailto:amps-bounces at contesting.com]
> On Behalf Of Bill, W6WRT
> Sent: Monday, February 01, 2010 12:08 AM
> To: 'Amps reflector'
> Subject: Re: [Amps] Plate Choke Resonances
> 
> ORIGINAL MESSAGE:
> 
> On Sun, 31 Jan 2010 23:04:26 -0500, "Gary Schafer"
> <garyschafer at comcast.net> wrote:
> 
> >
> >Maybe Bill could explain to us how there is going to be more voltage
> >appearing across the plate choke than there is across the tank circuit
> which
> >is in parallel with the choke. :>)
> 
> REPLY:
> 
> There isn't more. Where did I say there was? They are the same, but
> the tank components are far more likely to withstand the excess than
> the choke is.
> 
> 73, Bill W6WRT

My point is that you are worried about parallel resonance in the plate choke
and damage to it because of that. I am pointing out that the voltage across
the choke will be held in check by the tank circuit no matter if the choke
is parallel resonant or not.

Your example of disconnecting the antenna and driving the amp full power is
an extreme one. Many things would probably arc in that instance including
the plate tune capacitor and probably the bandswitch. The arcing of the
plate tune capacitor in some amps protects the bandswitch from arcing in
those situations along with other components. The plate choke being parallel
resonant or not will usually not be a deciding factor.

73
Gary  K4FMX