[hpsdr] Tiny preselector from HEROS - Some ideas.......

Henry Vredegoor henry.vredegoor at gmail.com
Sun Apr 19 08:21:13 PDT 2009


Hi Phil, Franz, All,

Good to hear that an I2C interface is now available and controlling this
preselector from one of the HPSDR boards could be made possible.

Another thing I think that would be nice too (to make this preselector more
"High Performance" ;-)  ), would be to see some graphic indication in the
spectrum display of the selected/resulting actual preselector passband.
(Calculated from the frequency, selected inductance/capacitance?)

I also think that the inherently manual variable aspect of a preselector
(shifting the passband of the preselector over the RF spectrum) would be
nice to be maintained.

This requires however that the main action of the software to take place in
the PC (in PowerSDR) and that the HPSDR board FPGA software only serves as a
"dumb" I2C controller.

I have however no idea if this is possible to implement and how complicated
this would be.

Any thoughts?

73,
Henry.



-----Original Message-----
From: hpsdr-bounces at lists.hpsdr.org [mailto:hpsdr-bounces at lists.hpsdr.org]
On Behalf Of Franz Hegener
Sent: zondag 19 april 2009 10:30
To: hpsdr at hpsdr.org
Subject: [hpsdr] Tiny preselector from HEROS


Hi Phil,
 
i have ordered the tiny preselector from HEROS too. 
In Germany we are some people who will try the tiny preselector with the
HPSDR.
 
Is it possible to provide us with the needed software for the I2C interface
option from Heros to use this nice combo?
This would be a perfect solution until Alex is available.
 
I read you feedback with the following possibilities:
 
1. Add support to PowerSDR for it's USB port
2. Modify the PIC code to read the Command & Control data from the Atlas bus

and select the correct relays depending on what frequency HPSDR is set to.
3. Replace the USB board with one fitted with an SPI or I2C open 
drain/collector driver chip(s) and send the required signals from Ozy or 
Mercury. This is basically how the relays on Alex are switched.
4. Use the 7 open collector outputs on Penny to control the band select 
relays plus 8 open collector drivers connected to J20 on Ozy.
5. Connect open collector/drain drivers to spare Atlas bus lines and add 
suitable  code to  Ozy to drive them.
 
 
Point 3. Is the best way in my eyes. 
 
73 Franz  DG1FHA
 
 


 1240154473.0


More information about the Hpsdr mailing list