My experience is to use air cored coils in preference to toroid types if possible for high power applications. If you must use toroids keep them cold by using a good high pressure fan or preferably i
Some of us don't have such large antennas as you, Peter. For 1 Watt ERP I would need approx 4kW RF. Anyone got any cheap 3 phase 500V bridge rectifiers ? The Litz wire around surplus now will do a b
Some of us don't have such large antennas as you, Peter. For 1 Watt ERP I would need approx 4kW RF. Yes, I am well aware of that - and that is why I mentioned I5TGC's LF antenna, which must be the s
Hi All, I have just received my Jan copy of Electronics World ( or Wireless World as it used to be known) with a article by two Italians on 136MHz. There are no call-signs given, and a lot of the ba
Hello group, I saw Jim (M0BMU) with a solid 'O' beaconing on 71.65kHz friday night. I could heard the signal going on and off, but QRM/QRN was to bad for a normal CW copy. John (G4CNN) seemes to hav
Hi Andy and All. Your approach to big amp design using a bridge cct is interesting but the concept is old hat. Like you say it is based on the decca design except for the supply voltage which you der
When 73 khz first became available to UK radio amateurs ANYONE that wanted permission to operate on the band got it. I know some that got it just in case, but never used the band. In more recent time
Hi All. I have made the point before on the reflector that 500 khz band is still in use by the marine services. The band seems to be very busy at times. I have recently heard traffic lists from Costa
With the advent of large LF amplifiers and proposed super large amplifiers capable of running up to 3kw output to the antenna, there is a requirement to keep the loading coil COOL. Method 1 Use micro
GI3KEV is 549 (daytime) upto 579 (dark) here, but I wasn't able to raise his attention yet. BTW KEV's signal is about 6dB down on MM0ALM 73, Rik ON7YD Thanks Rik for the observation on my signals, s
Hi all! Just as a matter of interest, I've compared the direct reception of 136kHz using a TS950SD, with a Datong converter using the TS950 as the ten-metre IF. Using a 40 metre inverted L antenna,
Recent messages here have indicated that a WOBBLE mode is evolving for transatlantic qso's. Am I correct with my assumptions that Station A wobbles once, station B wobbles twice C three times and so
I find the message from G3WKL about discussing CW on this list baffling, since CW either Normal or Slow is the prime mode of communications on both 73/136 khz. It is the only suitable mode available
Hi Bill and Colin, Congrats on getting going on 73kHz. Can you tell me how long you waited for your NOV? I applied at the beginning of December to the Radio Communications Agency at their new addres
Although most of the recent debates do not involve me in a controversial manner, I will volunteer to be the first to be banished from the list for discussing the use of CW on LF. This however, will n
As a founder of this Listserve, and the operator of the manual system that preceded it, I would like to ask all to reserve its usage to matters related experimentation, propagation and operating ske
Hello to Mike and Co I use an IC706 as a vfo on 13.6/7.3 mhz and divide by 100 to get on 73/136 khz. I also use it on 136 rx with the pre amp in. I have found it totally stable and satisfactory for b
Hi all, I say again there is no amateur ativity AT ALL in this area. I have put an enormous investment in time and effort to putting CT on the map and I have had only ONE QSO. If all this is the res
G'day Mal, There is magic connected with the old Cinema and the ability to send/copy morse code. And it helps to be completely in the dark to participate in both :-) If you do not have LF experience
