www.g4jnt.com/DownLoad/FourEbNauts.jpg All overnight sessions decoded, and things only began to fail at sunrise around 0730 It was a strong signal Andy G4JNT
I don't know that model - but with an HP tag it's likely to be one of the 'good ones' . In direct answer to your question, nothing will compare with Caesium - although I don't think you really meant
Rb is actually one of the lowest phase noise reference sources you can get - but really its all down to the OCXO used inside them. I believe they have better short term stability than Caesium, and ce
You have no control over the phase of the reference - only the frequency. GPS derived PPS signals, these days, are typically within a few tens or 100ns. This is still a complete cycle of 10MHz so you
Its the output that causes the problem, and anyway ferrite beads were suggested on the input to my receiver RF amplifier , the LTC5524. In retrospect I will probably change the distribution of gain i
I did it with a simple PLL VCO running at 66.6...MHz divided by 30. 10MHz reference input divided by 3, Phase comparator running at 333.333...kHz I used a superannuated obsolete MC145170 chip, but th
This is a synth that would do it - if you were to frig the VCO to go down to that frequency - and more to the point, could still get the MC45170 chip. http://www.g4jnt.com/VHF_Synth_Module.pdf These
He would say that wouldn't he - trying to sell multiplier / locking systems ;-) The phase noise on modern synthesizers really is good these days, especially if you use high comparison frequencies and
Be careful, it 'may' be OK, but I have heard that slippages can occurt. Due to difference in sample rates between the USB itself and 12MHz clock of the chip, when using USB isochronos mode (used for
Difficult one to test for. You'd have to be running a fully locked system, or at least everything running from one reference clock supplied to everything, then continuously monitor phase and look for
It is a not insignificant fact that Caesium Clocks are very expensive and have finite lives as their caesium "fill" moves from the source end to the ioniser. Current HP 5071's have a 7 year lifeti
Don't try decoding 16K21A mode using an old 1.7GHz XP machine with 2Meg. Poor thing sat there, its disc banging away (swapping memroy I assume) and completely locked. Needed a hard power switch and a
After transferring the saved file from just one recording session yesterday evening to my big PC that can cope with 16K21 decoding.... A decode straightaway. Quite strong at 9.9dB see below. My LF re
Hi Markus, yes. its all done in a simple 8 bit PIC using a crafty idea suggested by G3PLX back around the year 1997, but which can now make use of the better A/D Dconverters in the later chips (Apolo
Hmm, hadn't thought of that. I'll check my generated .WAV files via the waterfall plot in Spec Lab to make sure the I/Q is the right way round. Although, I think I did check it once and thought it al
One trouble with this LF narrow band stuff is that what has served for years as an excellent absolutely calibrated noise source for LF to HF, a 31 stage linear feedback shift register pseudo noise ge
Yes, here I will check vlfrx-tools, I think it's the right polarity but maybe not? I notice when I rx I/Q from an RTL2832 SDR I have to invert Q to get the sidebands the right way round which is s
The frequency in that file goes from negative to zero to positive. So I would have thought it would show leading moving to lagging , or vice versa But yes, there seems to be no standard for I/Q wave
