See "Test Model.png" attached. I was using an actual SDR receiver here to tune in and look at my Huff & Puff VFO Stabilizer and noted that the signal was very stable and did not move about on the spectum display. Neither was there any sidebands nor did it produce extra spurs on the display other than those the receiver's DDS produced. Hence no added spurs were seen from the H&P.
I was able to better see what could produce sidebands when I made changes to the circuit and I was also able to see when I was acheiving incremental tuning of some very fine degree. In contrast to circuit changes that resulted in the H&P making tuning locks in steps. I will then stay on the trail of the incremental tuning since I see now what it can really do. And I can see when I make a circuit change that results in unwanted sidebands. The USB receiver then enables me to see what ideas result in fine tuning capability and now I can progress along without being blind. The frequency counter and oscilloscope could not tell me these things and so now I am set to further this and hopefully will have a simplified and more traditional circuit for use here over the winter. Currently the VFO running in the range of 455 to 1455 kHz seems to be itself stable by virtue of its low frequency range and can then be used as it is without a frequency division scheme since the stabilizer appears to be doing a very good job to correct drift without visible spurs or side bands. I can thus simplify the circuit as I was doing here today and then explore it all and give you some useful data on its actual performance. In the next two weeks here I will be doing the study and then you can take over with the circuit and use it. I have a FET VFO you can use with it for use from 100 kHz to 150 MHz which uses a single 450 pF variable capacitor and makes band changes by coil switching only. I do not know how far my present H&P circuit is able to work in terms of up frequency into the HF region but you may want to explore and develop that yourselves. In the enclosed circuit diagram I use a 10 uF cap on the Q output of the 74HC74 which you may diminish or omit. Do not worry if this capacitor distorts the wave form of the signal output. It still works regardless of the wave shape. It makes the circuit more incremental from my experience here. Let me know if any of you find that it is so on your end? If not then scrap the 10 uF cap. Dan _____________________________________________________________________ PrivatePhone - FREE telephone number & voicemail. A number so private, you can make it public. http://www.privatephone.com [Non-text portions of this message have been removed] Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/soft_radio/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/soft_radio/join (Yahoo! ID required) <*> To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] <*> 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/
