You may want to take a look at the SoftRock V6 schematic, by using a purely digital clock generation circuitry, it's free to move around in frequency without changing any components on the Quadrature clock generator. All you would change is the input band-filter. Now if you have an old pre-selector unit, they usually have 100KHz to 30Mhz in six bands and use that as your front end filter and DDS for the source of your clock, you can move around all over creation without changing any components on the hardware.
The schematics to the V6 is available at the link below. < http://www.qrpradio.com/pub/Ham/SDR/SoftRocks/ > At 01:09 PM 4/15/2006, [EMAIL PROTECTED] wrote: >Ian: > > The receiver circuit that I have been looking at will allow > general coverage receive and the bandwidth of the channel should > reach 100 kHz. >The original circuit is run by a vfo and uses direct conversion at >the antenna. The vfo is phase shifted by a two winding toroid core >transformer. And the mixers are IC types with mini transformers and >diodes on the chip. > > Except for a frequency synthesizer you have a vfo in this case > and there definately is the ablity to tune from vlf to 30 > MHz. Band coil changes have to be made and the phase splitting > transformer might require a change to another version of itself for > portions of the HF band but may not neccessarily need changed > depending upon the core used. Below is a link where the circuit > file can be downloaded if it is still available. > >http://www.nitehawk.com/rasmit/quad_mixers.zip > >Dan > > >_____________________________________________________________________ >Call Anyone, Anytime, Anywhere in the World - FREE! >Free Internet calling from NetZero Voice >Visit http://www.netzerovoice.com today! > > > > > >Yahoo! Groups Links > > > > Cecil Bayona KD5NWA www.qrpradio.com "Windows the worlds most successful software virus" 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/
