Good point.. i have done that before: http://img94.imageshack.us/img94/2592/spikes2.jpg
spike is still there although less noticeable. On Sat, Dec 17, 2011 at 10:22 AM, George Allen <[email protected]>wrote: > Suggest that you remove the external clock input to the F5K, use the > internal reference and see if you still have the problem. Obviously, you > will be off by a different amount; but, with a warm F5K, the frequency > should be stable. > > George > K2CM > > ________________________________________ > From: [email protected] [[email protected]] > on behalf of Bill Dailey [[email protected]] > Sent: Saturday, December 17, 2011 11:11 AM > To: Jerry Flanders > Cc: Flex Edge > Subject: Re: [FlexEdge] Odd happenings every 9 minutes > > By the way... this glitch is nearly instantaneous... it look like it > happens for several seconds just because the FFT is responding to the large > jump... it is likely more than 50mhz.. that is just how the FFT smooths > it. I would presume there is something odd going on with image rejection > or something. > > On Sat, Dec 17, 2011 at 9:57 AM, Jerry Flanders <[email protected] > >wrote: > > > Might this result from the satellites coming in/out of view and the GPSDO > > switching among them? Maybe try it without the GPSDO. > > > > I am surprised you are within 100 microHz on your measurement - my 5000a > > synthesizer seems to _always_ be 20 -60mHz off. > > > > Jerry W4UK > > > > > > At 10:40 AM 12/17/2011, Bill Dailey wrote: > > > >> I don't know who to contact on this so I will put it here and leave it > up > >> for grabs. I have been dealing with this and trying to trouble shoot it > >> for a couple of months. Fairly complex setup: > >> > >> Flex-5000a PowerSDR version 2.2.3 (I havent checked other versions), > >> windows 7, i7 speed demon computer > >> IF offset 0 hz, dds offset 0 > >> Stanford Research DS345 Signal generator > >> Both disciplined to a Jackson Labs Fury GPSDO 10Mhz reference > >> Sending audio via VAC - all sample rates verified to 48khz > >> I am sending audio to fldigi (have verified with spectrum lab also, > >> identical results) > >> > >> Excellent frequency resolution.. right on where I would expect (within > >> about 0.1mhz) ...BUT..... > >> > >> Every 9 minutes there is some odd abberancy that occurs with either > >> powerSDR (probably), the radio or VAC that shifts the measurement by +50 > >> mhz. image of graph: http://img703.imageshack.us/** > >> img703/9382/spikesbf.jpg< > http://img703.imageshack.us/img703/9382/spikesbf.jpg> > >> I have tried various buffers and cant seem to affect the timing or the > >> magnitude of the shift. I used to get noise that would surge like this > >> with past powersdr versions so I am virtually certain this is a software > >> issue. > >> > >> Anyone have any suggestions of what may be causing this behavior? > >> > >> Doc > >> KX0O > >> > > > > > > > -- > Doc > > Bill Dailey > KXØO > _______________________________________________ > Flexedge mailing list > [email protected] > http://mail.flex-radio.biz/mailman/listinfo/flexedge_flex-radio.biz > This is the FlexRadio Systems e-mail Reflector called FlexEdge. It is > used for posting topics related to SDR software development and > experimentalist who are using beta versions of the software. > -- Doc Bill Dailey KXØO _______________________________________________ Flexedge mailing list [email protected] http://mail.flex-radio.biz/mailman/listinfo/flexedge_flex-radio.biz This is the FlexRadio Systems e-mail Reflector called FlexEdge. It is used for posting topics related to SDR software development and experimentalist who are using beta versions of the software.
