[Amps] Plate Choke Resonances

[Jim Brown]

On Sat, 30 Jan 2010 12:55:43 -0500, Carl wrote:


>----- Original Message ----- 
>From: "Bill, W6WRT" <dezrat1242 at yahoo.com>
>To: <Amps at contesting.com>
>Sent: Friday, January 29, 2010 11:56 PM
>Subject: Re: [Amps] Plate Choke Resonances


>> ORIGINAL MESSAGE:
>> 
>> On Fri, 29 Jan 2010 10:13:37 -0800, "Jim Brown"
>> <jim at audiosystemsgroup.com> wrote:
>> 
>>>
>>>The principal resonance is a parallel resonance with 
>>>its own stray capacitance. You should not have to short 
>>>anything to see this. 
>> 
>> REPLY:
>> 
>> The purpose of shorting is to find SERIES resonances with the grid dip
>> meter. You need to check for both parallel and series (i.e. with and
>> without the short). 
>> 
>> 73, Bill W6WRT

>Oh how true Bill! I was waiting for someone to catch that big error (-;

My comment was not an ERROR, but an observation. Of course you short it 
to look for series resonances. Yes, you must look both ways. And I repeat 
my recommendation to measure the impedance vs. frequency. 

73,

Jim K9YC