[hpsdr] Hermes Beta boards.

[Kjell Karlsen]

Hi Phil.

First, I wonder if you have received my e-mail where I commented the  
Hermes Gamma Schematics? I have not received any reaction from Tony on  
that e-mail. It is very important that the construction of the SMPSU is  
made according to the original construction to be sure the results are the  
same. I also think we must be sure the grounding is done in a proper way  
on the rest of the board.

I listened to the last teamspeak and heard that Jeremy (I think it was)  
suggested that we give the HPSDR community all infos for the Beta PCB´s  
and all measured data on the present board so that people that want it can  
make there own Hermes with USB interface.

To make more PCB without modifying it is not a way to go. The spurious  
radiation from the TX is all to high and the modifications I made are to  
time consuming to be advisable.

I think it might be possible to modify the layout and get a working Hermes  
with quite good performance just by removing the Power layer and replace  
it with a continuous Ground Plane. The power routing can be moved to the  
other layers. All critical tracks have to be moved and by improving the  
decoupling following my advice I think the results will be much better.

If someone want to do that it might be some interest by experimenters to  
buy just PCB´s. Making a list first to see how many that are interested  
and then decide what to do might be possible. I do not think there are  
many that will do it, but you never know!

I will follow the "LAN road" myself but I can assist if someone want to  
develop the USB further.

73, Kjell

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