[hpsdr] Pure Signal with Transverters

[Clyde Washburn]

I am pleased to report that Pure Signal can work very nicely on transverter bands as well, if you provide a suitable Tx mixer path
back to the IF frequency.

 

I my case I started with a custom 2m & 432 transverter, which used a +23dBm-class mixer for receive, driven at +25dBm.  Since the LO
amplifier is capable of +28dBm , I was able to increase the drive to it by 3dB, and then drive two +23dBm-class mixers at +25dBm
each.  The added Tx channel is driven from a Bird VHF/UHF sampler in the common feedline to my log-periodic 2m/432 antennas, and
applied to the mixer thru an attenuator adjusted for ~-17dBm output from the mixer, thru a 30MHz LPF (10m IF) to the Tx receiver
input.  There are 1KW FET amps following the tranvserter on both bands ahead of the sampler.

 

Operation is exactly as expected on the lower bands, and suppression of IM to the -55 to -60dB below PEP level was readily obtained.
Clearly future transverter designs need to be full duplex and handle large enough signals to be useful for predistortion!

 

__________________

Clyde Washburn, K2UE

k2ue at rochester.rr.com <mailto:k2ue at rochester.rr.com> 

82 Lasalle Pkwy

Victor, NY 14564-9610

585-317-7006

 

 

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