[Amps] (Perhaps) A plate choke too far ...

Carl km1h at jeremy.mv.com
Thu Jan 14 13:28:37 PST 2010


If you want a good laugh read thru all his "ideas"

Carl
KM1H

----- Original Message ----- 
From: "James Colville" <jimw7ry at gmail.com>
To: "Radio WC6W" <wc6w_amps at yahoo.com>
Cc: <amps at contesting.com>
Sent: Thursday, January 14, 2010 11:43 AM
Subject: Re: [Amps] (Perhaps) A plate choke too far ...


> What about this theory? See the lower part of the page.
> 
> http://www.kk5dr.com/chokes.htm
> 
> 
> 73
> Jim W7RY
> 
> 
> 
> On Thu, Jan 14, 2010 at 8:32 AM, Radio WC6W <wc6w_amps at yahoo.com> wrote:
> 
>> Hi Hardy,
>>  True... but, the DC will "kill" the core at HF.
>>
>>  Look at the bottom of page 129 on this link
>>
>> http://fair-rite.com/newfair/pdf/CUP%20Paper.pdf
>>
>>  to see the ... damage.
>>
>>  And operating on the curve would also likely introduce some distortion.
>>
>> 73 & Good morning,
>>  Marv WC6W
>>
>> http://wc6w.50webs.com/
>>
>> --- On Wed, 1/13/10, Hardy Landskov <n7rt at cox.net> wrote:
>>
>> > From: Hardy Landskov <n7rt at cox.net>
>> > Subject: Re: [Amps] (Perhaps) A plate choke too far ...
>> > To: "Radio WC6W" <wc6w_amps at yahoo.com>
>> > Date: Wednesday, January 13, 2010, 7:36 PM
>> > The whole object of an RF Choke is to
>> > kill the gain of the tube at low frequencies and DC while
>> > looking transparent at 1.8 through 30 MHz right? Mu has no
>> > meaning a DC, neither does XL.
>> > I guess I am not understanding this thread.
>> > Hardy N7RT
>> >
>> >
>> > ----- Original Message ----- From: "Radio WC6W" <wc6w_amps at yahoo.com>
>> > To: <amps at contesting.com>
>> > Sent: Wednesday, January 13, 2010 8:06 PM
>> > Subject: [Amps] (Perhaps) A plate choke too far ...
>> >
>> >
>> > >   The other day, just for fun, I swept
>> > a bunch of ol' RF chokes --  solenoid wound, pie wound,
>> > etc.  All of them exhibited nasty resonances somewhere
>> > within the HF spectrum.
>> > >
>> > >   I then wound a few experimental coils
>> > on some toroids and one on a type 43 core worked
>> > exceptionally well -- very flat response with no resonances
>> > anywhere below 50 Mhz.
>> > >
>> > >   The only gotcha with this part is
>> > that in a real world application the DC plate current would
>> > saturate the toroid, killing the mu & the uH's.
>> > >
>> > >   Now here's where this concept crosses
>> > over in the silly side...
>> > >
>> > >   The saturation problem could be
>> > overcome by running an out of phase DC current, servoed by
>> > the plate I, through a 2nd winding on the core.  This
>> > second winding would need to be RF isolated with a choke of
>> > its own but, for a single turn winding a 10uH (air core)
>> > choke would be sufficient. The required single turn current
>> > would be on the order of 10-15 amps. Sounds bad but, no real
>> > voltage is required -- 10 Amps at .1 volt is only a
>> > watt.  In a fortunate circumstance, this current might
>> > be obtained "free" in series from a DC heater supply.
>> > >
>> > >   Searchin' around the all knowing
>> > internet only uncovered a similar scheme to cancel the plate
>> > DC in an "audiophile" single ended output transformer.
>> > >
>> > >   Has anyone ever see this done?
>> > >
>> > > 73 & Good evening,
>> > >   Marv WC6W
>> > >
>> > > http://wc6w.50webs.com/
>> > >
>> > >
>> > >
>> > >
>> > > *
>> > >
>> > >
>> > >
>> > > _______________________________________________
>> > > Amps mailing list
>> > > Amps at contesting.com
>> > > http://lists.contesting.com/mailman/listinfo/amps
>> >
>> >
>>
>>
>>
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