[Amps] parasitic suppressor for six meters

Bill Turner dezrat at outlook.com
Sun Jul 15 10:20:59 EDT 2018


------------ ORIGINAL MESSAGE ------------(may be snipped)

On Thu, 12 Jul 2018 16:24:39 -0600, you wrote:

> I'm thinking
>about replacing the two burned resistors with a single 22 ohm 5 Watt metal
>film resistor, and trimming the inductor to a single turn. Does this seem a
>reasonable change? Does the tube require any parasitic suppressor at all?
>
>73,
>
>Jim W8ZR

REPLY:

Many amps have parasitic suppressors but actually don't heed them at
all, especially if the leads from anode to RF choke and tune cap are
very short. I would try the amp without the suppressor, bringing up
the plate voltage slowly in class AB mode and see if you get lucky. I
have built several amps using an 8877 on HF ( not VHF) without a
suppressor and all were perfectly stable.

I suspect many commercial manufacturers put in a suppressor "just in
case" or because customers want to see one there. 

73, Bill W6WRT


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