Hi Chris, > What about Softrock Tx? That would generate the RF.
Presumably the Softrock Tx is intended to be fed with I and Q from a PC. It should be possible to run two instances of the associated software and let one of them transmit an upper sideband while the other would transmit the lower sideband. One would just have to take the sum of the two I/Q audio signals and feed into the Softrock. It should be possible to run both instances of Softrock in the same computer and to get the summed audio from the soundcard. On systems where one can open the same device from several user applications the device will output the summed audio signal properly in I/Q format:-) 73 Leif / SM5BSZ > > Chris > G4NUX > > > On 12 Oct 2009, at 22:28, Leif Asbrink wrote: > > > Hello Jose, > > > > > I have seen no software capable of generating it so far. Actually, > > it > > > would require two sideband generators. I am not sure if a single > > sound > > > card could actuallydo it. > > It is a trivial thing to generate ISB in the PC and send it to the > > soundcard. Nobody is interested because there is not any hardware > > available to frequency shift it to RF and to amplify to a suitable > > power level. > > > > One could make a signal with about 5 kHz bandwidth available on a > > single > > audio channel. It would match an SSB transmitter with a passband from > > e.g. 300 to 5300 Hz. One could also make it available as an I/Q pair > > with > > i.e. 300 to 2500 Hz passband (stereo). That would fit a simple > > quadrature > > modulator. > > > > > ISB has not been usual among hams, but could be interesting. Once > > I read > > > a proposal for using SSTV on one sideband and audio on the other, > > > but have heard noone doing that. > > The problem is the amplifier chain. Conventional equipment does not > > have the bandwidth in SSB mode. > > > > I think we will see experimenting with ISB and other new modulation > > schemes > > when we have more digital equipment around. The HPSDR, Mercury > > +Penelope > > would allow voice+SSTV as ISB or in some suitable digital format > > and everything would be in software. > > > > I could easily transmit ISB with my Linrad transmitter, but I do not > > have any second signal besides the microphone (No SSTV.) It will not > > be interesting until there is a reasonable chance of meeting someone > > on the bands who is capable of receiving both sidebands. I am sure > > we will > > see it some day because it is an obvious thing to implement in a SDR > > transceiver:-) > > > > 73 > > > > Leif / SM5BSZ > > > > > >
