[TenTec] Ig drift on amps

Dr. Gerald N. Johnson geraldj at storm.weather.net
Sun Feb 8 23:14:32 EST 2009

On Sun, 2009-02-08 at 21:36 -0600, Bob McGraw - K4TAX wrote:
> The output of the amp is indeed a Pi-L network.  These work great and have 
> been in BC transmitters very successfully for years.  I wish more companies 
> would use Pi-L networks in their amps. Better attenuation of harmonics, 
> lower currents in the coils and components and a better match.  All at the 
> cost of increased costs.
> I can't imagine any amp today being able to handle a 300 ohm load on its 
> output at rated power.  That's an SWR of 6:1.

He was talking about the design impedance at the junction of the Pi and
the L. Higher than the load Z, lower than the plate Z. 300 to 600 ohms
are common values for that mid point in the output network. Higher takes
more L section coil and a higher loaded Q but allows smaller load
> 73
> Bob, K4TAX

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