And on top of those projects add the VW beetle restoration, '59 B95 Berkeley
and Berkeley SE328.
But now spending most of my time designing kits for teaching radio and physics.
Oh, yes , day time job as well.
73
Bill wa4lav
________________________________________
From: amps-bounces@contesting.com [amps-bounces@contesting.com] On Behalf Of
Fuqua, Bill L [wlfuqu00@uky.edu]
Sent: Saturday, January 30, 2010 4:16 PM
To: Carl; ka4inm@tampabay.rr.com; amps
Subject: Re: [Amps] Tuning amplifiers
I kind of like the tuning method used by the 30S1. Perhaps a variation of that
would be useful.
That is, knowing the gain of the amplifier when properly tuned, measure the
ratio of output power to input power.
With proper drive ,even pulsed, you can fine tune to that ratio.
Does anyone make a power gain meter?
Some old designs in QST looked at the ratio of input voltage to output voltage
directly at the tube. This ratio would be correct when
the plate was properly matched to the load. I recall one that actually varied
the bias to maintain linearity on high peaks. That is sort of
a quasi-daf amplifier.
Speaking of projects I still have to get back to my 4-1000A amp and 30S1 and
Desk KW. But where does anyone find spare time
these days?
73
Bill wa4lav
________________________________________
From: amps-bounces@contesting.com [amps-bounces@contesting.com] On Behalf Of
Carl [km1h@jeremy.mv.com]
Sent: Saturday, January 30, 2010 3:58 PM
To: ka4inm@tampabay.rr.com; amps
Subject: Re: [Amps] Tuning amplifiers
With GG triodes, tetrodes, or pentodes, the grid current is the most
sensitive tuning indicator.
For grid driven tetrodes or pentodes the screen is the most sensitive tuning
indicator as well as the most easily damaged by mistuning.
Carl
KM1H
----- Original Message -----
From: "Ron Youvan" <ka4inm@tampabay.rr.com>
To: "amps" <amps@contesting.com>
Sent: Saturday, January 30, 2010 2:59 PM
Subject: [Amps] Tuning amplifiers
> Anyone:
>
> I am confused by some of the things I am reading here about tuning,
> but I have long heard triodes and tetrodes are tuned differently,
> I have never figured out why or what, could someone enlighten us and I
> assume pentodes are tuned like tetrodes, right?
> (I have been tuning tube amplifiers for over 40 years now, normally
> with a swept test signal, frequently with -20 dB of drive.)
> --
> Ron KA4INM - He who attacks the fundamentals of the American
> broadcasting industry
> attacks democracy itself. -- William S. Paley,
> chairman of CBS
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|