Jim, Markus, and the group: First of all, many thanks Jim for doing those measurements. I don't have the test equipment to do these things and I am too far away from Rugby. Your results seem to say t
It falls off only at -40 dB/decade, as expected for the click of a t^2 pulse start correction: this should have said -60 dB/decade. The time-domain pulse envelope formula is from http://www.eurofix.t
Hi Peter, went through your calculation and basically reproduced your result, with only minor differences: Following your reasoning, the power in the last bin would be 10^(-59.54/10) * 1.37^2 = 2.087
Dear Peter, LF Group, I tried some rough field strength measurements on the Loran noise in the 136kHz band, in an attempt to confirm your calculations. A a field strength reference, I injected a know
Alan: Yes, it's true that if the signal is wider than your receiver and is coherent (like a pulse), then the SNR will increase if you widen the bandwidth, inspite of the fact that the noise increases
Peter, In one way I think you are right. If you were to select one line you would not be able to hear it. The effect is a little like FM. If you listen to a WB FM signal with a narrow band receiver y
From G3PLX: Some small corrections to the calculation of the erp of a LORAN line... The mean power of a LORAN transmitter is a little lower than I said. If the published peak power is P and the Group
From G3PLX: I calculated the radiated power of a LORAN line now, but I would like other people to check if I did it right, because the result is surprisingly small. The spectrum measurement made at R
Marco: Thanks for the info about the LORAN transmitter. That's very useful, and it's surprising how low is the mean power. If it's 7.5kW at 180 pulses/sec., then for example the Lessay chain transmit
I found it :-) From the manual of the glorious AN/FPN-44A: "The station output power is 100kW at the standard sampling point. The standard sampling point occurs 25 microseconds after the start of eac
Marco: Thanks for the info about the Sellia Marina transmitter. Is this still operating? I thought that the Mediterranean chain had closed down. Hi Peter, that was about 10 years ago. Yes, it's all
Alan: Yes I have spent some time at the Megapulse site, and that tells me all the power levels, but I assume these are given as the peak pulse power. What I need now is to convert these to mean power
Lessay and Sylt are quoted as 250kW, there are even powers for the western Chayka system ! Exact locations are also given. Also at a lot of locations you will receive signals from more than one stati
Peter have you looked at the "megapulse" web site for power levels. ERPs may be calculatable if we know the mast heights....these may be available elsewhere. http://www.megapulse.com/chaininfo.html L
Hi Peter and group, If you are close enough to receive surface wave from DCF39 and surface wave from Sylt, then a ratio of the DCF39 carrier level to the level of a typical Sylt LORAN line (at midday
Wolf: That would be another way to get a calibration, so long as we also knew the emrp of DCF39. If you are close enough to receive surface wave from DCF39 and surface wave from Sylt, then a ratio of
Hello Peter, Would a "relative" level indication be helpful too ? I have no calibrated measuring equipment, all I can measure is how many dB's weaker a particular Loran line is compared to the DCF39
From Peter G3PLX: Does anyone have any information about the actual level of spurious emission from the LORAN transmitters in the 136kHz band? The only specification I know of says something like the
