[hpsdr] What mic are you using with Penelope? VK6BMT

[Merv Thomas]

Hi George,

I have just finished the same kit.  Remember that without one of the 6 relay 
circuits being energised at the time you transmit and without a reasonable 
load on the output of the LPF Penelope will be working into an open load 
with possible serious consequences to Penelope.  I forgot when testing my 
kit but fortunately I was not using Penny as the RF source.

I assume that there could be a problem also if the wrong relay is 
energised - say 10m and you are actually transmitting on 160m as the VSWR 
may be too high and cause a problem for Penny. Of course this should  not 
happen if the correct control boxes are set in PowerSDR.

I am learning the hard and expensive way to be very cautious as I have had a 
lot of expense fixing/replacing boards - probably being my age does not 
help!!

I found I could improve the VSWR through the LPF board by utilising my MFJ 
SWR Analyser as the signal source into the LPF with a 50 ohm load on the 
output.  I then squeezed or widened the gaps between windings on the coils 
to achieve as low as possible SWR.

Merv  VK6BMT