Hi Gary, Alan, yes, as Alan says, class E amplifiers are very forgiving. In addition to Tonne's program and Alan's Excel spreadsheet you may want to have a look at Nathan Sokal's QEX article to learn
Hi Gary, If I remember correctly, DF3LP's design is "class-C-ish". Your FET will probably run cooler if you use a class E output network (still with 50/50 squarewave drive). The program at http://www
Congratulations to Mal and Wolf for the first (known to me) international amateur QSO involving 600 meters! [email protected] skrev: Hello Mal, Many thanks for this nice opportunity, and for being my
Dear All, today May 24 is the 163:rd anniversary of the first telegraphy message! http://memory.loc.gov/ammem/today/may24.html There is a nice picure of "/P operating" at the end of the page :-) 73 J
ERROR! LMCW is much older! For example, look at section 7 of Rik's (excellent!) page, Nihil novum sub sole, http://www.qsl.net/on7yd/136narro.htm#NihilNovum In fact, LMCW is not an "amateur invention
Looking at the patterns: am I right to conclude that not-so-perfect ground will only attenuate the surface wave (radiated at 0°) but will not affect skywave (or even improve it a bit)? I don't know.
Hello, If there are a few dBs still missing when all near field losses have been taken into account, I would guess it is time to blame the non-perfect ground. The lower the ground conductivity, the w
Dear Jim, it would be very interesting to have a look at your TX design. Attached is a schematic of a push-pull class E amplifier. I have had good results with such a circuit at QRP levels on 80 and
Ooops, I was thinking of a "point source"... A 40 meter wire is of course a rather "stretched" point so there will be a "tent" instead of a cone :-) If the topload L >> H then the "Laurencian Area" c
Dear Jim, LFers, A very interesting experiment Jim! I find it amazing that such a small increase in average height can make such a dramatic improvement in efficiency! Were there any trees near the ce
Jim, the LF group, thanks for sharing a very interesting experiment! This raises the following question: http://web.telia.com/~u33233109/ I bet the answer contains the words "it depends..." ;-) 73 Jo
I just downloaded the 574 page book here: http://k6mhe.com/ click "ANTENNA TOPICS", go to the end of that page and click "Radio Antenna Engineering" 73 Johan SM6LKM
Well, I think the T/M/O system is more efficient than ZHN 3/2/1 for reporting QRSS beacons. These days there can be many resons for ZHP, for example "ZHP hard disk failure" or just "ZHP computer alle
It is fun to see how much interest and activity the advent of 500 kHz has stirred up! Maybe it is time to brush the dust off the Q code "QOA" which has never been used on ham bands before :-) 73 Joha
Hi Dave, I agree 110% with you. We already have the RSGB LF and the U.S. Lowfer reflectors and most LF enthusiasts seem to be there already, with some overlap. We don't need another forum. These days
Hello Claudio, I measured the "backwave" from SAQ a couple of years ago and found it to be 17dB below the key-down level. I have no exact figure but since the nominal output is 200kW, and if -17dB is
