[Amps] Doorknob quality

[Evert Bakker (PA2KW)]

Hello Jim en Colin,

Thanks for info.

It will be an extra capacitor switched in parallel with the variable plate
capacitor (so within the tuning circuit)
I "cooked" already two of these (different) doorknobs in just a few minutes.


I guess Colin is right, it must be the high currents.

I have no idea what the currents are, and often they are not stated on the
websites which makes selecting the proper device difficult.

I looked at
http://www.surplussales.com/capacitors/Trans_Coup_Caps/cap_trans.html
And saw the TDK and Murata capacitors are labeled as high current.

Any suggestion before making an "investment"?

73's, Evert PA2KW  


-----Original Message-----
From: Jim W7RY [mailto:w7ry at arrl.net] 
Sent: Sunday, February 22, 2009 02:14
To: evert at pa2kw.com; amps at contesting.com
Subject: Re: [Amps] Doorknob quality

Are these for tune or loading padders? If not what function will they serve?


73
Jim W7RY

----- Original Message ----- 
From: "Evert Bakker (PA2KW)" <evert at pa2kw.com>
To: <amps at contesting.com>
Sent: Saturday, February 21, 2009 4:22 PM
Subject: [Amps] Doorknob quality


> Hello,
>
>
>
> When using doorknob capacitors for RF tuning circuits, is there something
> special I should aware off?
>
> (special quality, specific "family")
>
>
>
> I'm looking for on a 300pF/30kV in my 160 mtr amplifier
>
>
>
> Thanks
>
>
>
> 73's, Evert PA2KW
>
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>


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