[Amps] 6 meter 8877 amplifier

[Jim W7RY]

You're right Bill. But it's poorly written./
73
Jim W7RY


2. You do not need an input matching circuit. The 8877 input impedance is 
very
close to 50 ohms anyway. If you insist on a perfect match, the antenna tuner 
in
your transceiver can do the job.

3. You do however, need a parallel resonant tank in the input circuit to 
provide
the 'flywheel' effect. I used a Q of five. This requires a 9-position switch 
for
the input and a means of tuning each band. I used individual toroids and 
mica
compression trimmers. Do not try to 'tap' a toroid. Use 9 individual 
toroids.




-----Original Message----- 
From: Bill Turner
Sent: Wednesday, December 12, 2012 9:52 PM
To: Jim W7RY
Cc: Amps
Subject: Re: [Amps] 6 meter 8877 amplifier

ORIGINAL MESSAGE:
On Wed, 12 Dec 2012 21:32:10 -0800, W7RYwrote:

>What a huge misconception! We have discussed this since the cows started to
>come home! You NEED a tuned input.
>
>
>73
>Jim W7RY

REPLY:
I'm afraid the misconception is on your part, Jim. I NEVER said you
don't need a tuned input circuit. I said you don't need an IMPEDANCE
MATCHING circuit for the 8877. You do need a parallel resonant tank
circuit in the input for the "flywheel" effect, but that has nothing
to do with impedance matching.

Please read my ENTIRE post again.

73, Bill W6WRT