F6EHJ wrote: > Including all the hardware control (including DDS LO) imposes the LO (and > the DDS) and the associated circuits I suppose, which reduce dramatically > the opportunity to have its own hardware and exact duplication will be the > only way to succeed.
I think that the proposal of Tom Holden is a very sensible one, and I probably will write the hardware-controlling part of the program in two sections. The first will call an external DLL using a published interface, not tied to the specific hardware used. The DLL itself will then translate the requests into the specific commands needed for the hardware on hand. In this way everybody who would like to use a different hardware could rewrite just the DLL for his specific needs. > Considering the transmit section a simple12 kHz I/Q output would be fine > and enough. It could be generated with a secondary sound card to avoid > sophisticated switching, in this case a single RX/TX command will be needed. I don't know which sophisticated switching you are referring to, but if you mean an output sampling speed during Tx time different from that used during Rx time, switching the sampling speed of a sound card is quite easy, so a separate card in the PC is not needed. If instead you mean switching the line-out of the card from the speakers (while receiving), to the I/Q up-mixer (while transmitting), then a simple relay will do, driven by the PTT signal, which the program could activate by using just a pin of the parallel port. BTW, I have reports that say that some of my programs work correctly with external USB sound cards, so this could be a solution for those who have obsolete chip sets in their laptops (e.g. not capable of 96 kHz sampling). 73 Alberto I2PHD ------------------------ Yahoo! Groups Sponsor --------------------~--> Get fast access to your favorite Yahoo! Groups. Make Yahoo! your home page http://us.click.yahoo.com/dpRU5A/wUILAA/yQLSAA/ELTolB/TM --------------------------------------------------------------------~-> Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/soft_radio/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
