Dear LF Group, To try to get an idea of the order of magnitude of ionospheric effects and RX drift on LF signals, I recorded about 30 hours worth of the spectrum of DCF77 at high resolution - see the
Hi Building a Shera style GPS standard is not complicated at all. There are only two critical components - the GPS receiver and the (preferably OC-)VCXO. The rest of the circuit is built from inexpen
At 11:01 16/04/2002 +0100, you wrote: Not sure if the Doppler shift due to orbital wobble will affect the modulation in the same way it does carrier frequency. Are there any physicists out there who
[...] Not sure if the Doppler shift due to orbital wobble will affect the modulation in the same way it does carrier frequency. Are there any physicists out there who can confirm this ? [...] I thin
Does ZDF still make use of TV sync to distribute standard time and frequency in Germany ? This signal received from Astra could be relied on as being highly accurate when this was the case and severa
The typical Doppler at end-of-life of a GEO satellite is about 40 meters per second. That translates to about .02 Hz at 136 kHz. I don't know what can be expected at midlife, perhaps an order of magn
[...] Thus the phase measurements must be made wrt an analogue TV transmission. [...] What about analogue TV via Astra satellite ? There are dozens of analogue channels on this bird, and I am told s
I got out my copy of ISO/IEC 13818-1 which defines the transport system for digital televison. DTV systems have an accuracy defined by their 27 MHZ system clock. Everything is defined by that clock f
Wolf The sharp phase transition may well be a broadcasting centre handover. Using TV frame reference is a neat idea, because in order to stop the most destructive type of co-channel interference the
Hello group, I made two phase plots of 1.5 hours length yesterday, the first with MSF (60kHz), the second with DCF77 (77.5kHz). To calibrate sample rate and the receiver's LO, the 15625 Hz TV sync ("
[email protected] schrieb: Hello Jim, Uwe and group, .......... Thanks Uwe for the signal gallery. From your QTH, you can be sure to receive Loran from Sylt via groundwave ! Regards, Wolf DL4YHF. Hi Wol
Dick Rollema wrote: To All from PA0SE Not all TV-stations derive their sync-signals from stable frequency sources. Harry, PA0LQ, has investigated this matter some years ago and seemed to remember tha
To All from PA0SE Not all TV-stations derive their sync-signals from stable frequency sources. Harry, PA0LQ, has investigated this matter some years ago and seemed to remember that BBC1, BBC2 and the
Hello Jim, Uwe and group, Yes of course an LF broadcaster can only be used as reference if he is quite close to your station. Groundwave propagation must be dominant throughout the observation period
Dear LF Group, Thinking a little more on this idea, it seems to me that using LF standard frequency signals as a phase reference has a basic flaw - the reference phase signal received at the stations
James Moritz schrieb: Dear Wolf, Alan, LF Group, ..................... for the reference - perhaps Droitwich on 198kHz will do. ............... Cheers, Jim Moritz 73 de M0BMU Hi Jim es all, indeed Dr
divider , the counting process will come to a stop when the signal level falls below some threshold, so output from the divider will start and stop at points in the cycle which depend on the amplitud
Dear Wolf, Alan, LF Group, I think I can set up this kind of experiment and leave it running fairly easily - but a couple of queries: Signals like MSF have on-off keying. Feeding this signal into a d
Dear LF group, I am planning an experiment based on an idea from Alan G3NYK. The idea is to monitor the phase variation of strong signal on LF over day and nighttime. It may be interesting to find ou
