[hpsdr] Entry point

[ct1izu]

----- Original Message ----- 
From: "AI2Q" <ai2q at roadrunner.com>

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> Having successfully built a G3XJP STAR (Software Transmitter and 
> Receiver),
> which is now my main multi-band rig (along with a 600W homebrew MOSFET
> amplifier), I'm interested in the HPSDR project. My question is, what is 
> the
> best route to entry in either (a) the TAPR or (b) the pending UK design?
> Where does a newbie start?



Well you will definatley by a skilled hardware man to have done the Star 
Transceiver. The CURRENT  minimum with your skills
will require the Atlas back plane, Magister and  Mercury  from TAPR and 
Penelope from Gerd DJ8AY g.loch at nt-electronics.de

Pen has about a half watt tx out so you can replicate the Star tx  fron the 
2N3866 on the Magic Roundabout  onwards. For RX the Star low level
BPF's are excellent but I would suggest you modify another LPF to high pass 
configuration and put this ahead of the Merc RX input and if necessary
use the final AMP LPF on TX/RX to form a wide HPF/LPF set.

In practice here even with my 1100 foot Rhombic I find the HPF alone  in the 
front end provides sufficent atenuation. Grey line is about the only time I 
might see some
overload on the Rx ADC and this is easily cured by moving up an octave on 
the filters.

I guess its too much to hope you might be a software person. The Star DSP 
just begs to be mated with the HPSDR hardware for those hams who want
a stand alone radio but I guess it will never happen.

If you can wait Hermes may be the cheaper option, the intergration will 
certainly give give some cost savings.

Mail me off list if you need further clarification on any points.

Shel CT1IZU



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