Re: [softrock40] si570 samples
- On 28/03/10 16:50, Eric Söderman wrote:
>Excellent and very interesting. Bob G8VOI was the lucky winner of the
> That presentation can be downloaded here:
> Very cool to see the softrock connected to the ezDSP. The antenna is
> also interesting. :-)
> Eric SA5BKE
ezDSP development kit raffle for those ordering the SR63ng kit, so hope
to hear more in the future.
I like the antenna idea as it seems to be a lighter and more supportable
structure for a large 160/80m loop than the one that I had wrecked by
I have used quite a few magnetic loops, an indoor 3 foot diameter loop
of 3/8" diameter soft copper tuned with a standard capacitor on which I
worked all over Europe on 40m and 7W max, over 7W the capacitor started
to arc over.
The next one was an octagonal loop with 1m sections (22mm copper) and
tuned with a vacuum capacitor that took the full 100W on 80m.
An octagonal one of 8x 2m sections of 28mm copper tuned with a vacuum
cap (100W) for 160/80m and worked Stateside on 80m with it, all 80m
Stateside contacts I have made was on this antenna before it crashed and
smashed the capacitor. The difficulty in supporting such a structure in
the face of 60+ MPH winds eventually told.
My latest is 8x 1.5mm of 22mm copper tuned with a vacuum cap, but it
needs feed adjustments as the SWR is ~2.8:1 on 80m, warmer days should
see that in operation. For this one I have placed the vacuum cap at the
bottom which should help it to survive strong winds.
They work and they work surprisingly well.
73 ... Sid.
> On Thu, Mar 25, 2010 at 4:06 PM, Milt Cram <w8nue@...--
> <mailto:w8nue%40arrl.net>> wrote:
>> I can assure you that there is on-going work to provide transceiver
> capability for the RXTX without using a PC. I have demonstrated SSB
> receive capability using the TI eZDSP stick for SSB demodulation and the
> Kees/John Si570 controller for VFO. Others in the Austin Texas QRP
> (AQRP) club have demonstrated a dsPIC/codec combination for SSB/CW.
> This demo also uses the Si570 controller, which is a project of a few
> members of the AQRP club. George, N2APB also made a presentation at
> MASSCON last week that combines the RXTX with the TI eZDSP stick and the
> NUE-PSK modem for PSK operation without the PC.
Sid Boyce ... Hamradio License G3VBV, Licensed Private Pilot
Emeritus IBM/Amdahl Mainframes and Sun/Fujitsu Servers Tech Support
Specialist, Cricket Coach
Microsoft Windows Free Zone - Linux used for all Computing Tasks