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Wish list, and other stuff


Tommy Henderson
 

I am measuring about -118 dBm +/-2 here on Rx which is about right for an NE602 input device.  I do like the audio gain turned up.  I am also measuring output power at about 3.5W which is close enough.  I have not tried to tweak the coils, but believe it should not make too much difference.  Nice 3dB bandwidth on AF, as good as the DSWII.
Should be a winner in the field this summer, easy to operate controls on top.


Tommy WD5AGO


Dave Benson
 

Tommy-

Thanks for the measurement!  I'm no longer set up to measure MDS- I don't have a capable set of attenuators any more.

-118 dBm sounds about right.  The receiver input is losing 6-7 dB because the pick-off point for the W7EL T-R switch is at the PA drains- a 10-ohm impedance. Without adding complexity, the receiver input could have been taken right at the antenna. More gain- but image rejection would suffer badly. The design uses high-side injection and the lowpass filter rolloff for an image rejection of ~70 dB.

73- Dave, K1SWL

On Fri, Apr 20, 2018 at 7:53 AM, <wd5ago@...> wrote:
I am measuring about -118 dBm +/-2 here on Rx which is about right for an NE602 input device.  I do like the audio gain turned up.  I am also measuring output power at about 3.5W which is close enough.  I have not tried to tweak the coils, but believe it should not make too much difference.  Nice 3dB bandwidth on AF, as good as the DSWII.
Should be a winner in the field this summer, easy to operate controls on top.


Tommy WD5AGO