[Lowfer] An interesting discovery today;;;

[jrusgrove at comcast.net]

Andy

A variable voltage power supply is convenient for adjusting the output power. The difference between 
750 mW and 1 W is only a little over a dB...but down at the visual noise floor with Argo, 1 dB can 
make the difference between barely there and thick white lines.

Jay


----- Original Message ----- 
From: "Andy - KU4XR" <ku4xr at yahoo.com>
To: <lowfer at mailman.qth.net>
Sent: Sunday, December 21, 2008 7:01 PM
Subject: [Lowfer] An interesting discovery today;;;


> MERRY CHRISTMAS all:
>
> I removed quite a few turns, and rewound the ant. end of my
> variometer today. Tuning is smooth, and quite sharp at resonance.
> I checked my PA current ( 40 mA ) and PA volts ( 18.74 ), and if
> my math is correct, I,m only generating about 750 mW in the PA.
> Assuming ?? 90 percent efficiency, that would come to around
> 675 mW into the filter. I have NO IDEA what's actually getting
> into the ether. I think it was Jay who asked me if I was getting
> the full 1 watt input; calculations show that I'm not. I think I
> need to build me a 24+ volt power supply for a little extra umph.
> What's amazed me is the reports I've received have been at the
> lower power level. I wonder how much difference the extra 1/4 watt
> would make ??
>
> Andy - KU4XR - EM75xr - Friendsville, TN.
> LOWfer Beacon " XR " @ 184.322 KHz ( QRSS-60 )
> Coordinates:  N:  35* 43' 54" - W:  84* 3' 16"
> http://www.myspace.com/beaconxr
>
>
>
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