What everyone who points to ON4UN's "single raised raidal" system seems to forget is that John's 80 Meter system is installed ABOVE HIS 160 METER GROUND SYSTEM ... that system is "approximately 250
Most, if not all, of Florida is 100 MPH or 110 MPH territory. I would not consider leaving 20' of Rohn 45 above the guy point even with a small tribander (C-3, TH3, TA33, A3, etc.). Such an installa
This is the very essence of beam formation and the mechanism responsible for antenna gain/pattern. If an antenna has a pattern, ie. it radiates other than equally in all directions, it has gain. Cer
Since none of the experts has responded, I ran a home made model of the Cushcraft XM402 through AO and rotated the reflector around the boom. The model was run in free space with no other antennas p
L.B.'s results indicate that my model is on the right track (the loading losses are about 1dB) so I decided to re-run the test over ground. I chose 75 feet again with no other antennas, guy wires or
One caveat ... I haven't modeled the Force-12 40 meter antennas (linear loading is a bit beyond me right now). However, to get a good feel for the nature of the 40/15 stack problem I build AO models
True. BTW, "riding the load" is verboten, too. Not that anyone pays attention to the prohibitions on riding either the ball or the load ... at least so that I've seen on broadcast sites. 73, ... Joe
Anyone out there have an old Cushcraft R7 that has seen better days setting in a garage or basement that they would be willing to let go for parts? I'm particularly looking for the 20/30 meter traps
Does anyone have a model for the Bencher Skyhawk? -- FAQ on WWW: http://www.contesting.com/towertalkfaq.html Submissions: towertalk@contesting.com Administrative requests: towertalk-REQUEST@contestin
In practice, a single capacitor placed in the "ground" lead of the un-un should be all that is necessary. The un-un will provide the dc path from input to output (the relay operating current is smal
Probably the most common (at least I've had them on every truck I have used or built) mast on TV trucks is by Wil-Burt Manufacturing in Orrville, Ohio. At one time the "standard" was a either 48' or
Correct ... I had to replace a 56' mast on a TV remote truck last summer and the mast alone (air system, etc. was already in place) ran very close to $10,000 (through our truck builder). I no longer
Rather than fight with a five element sleeve driver, why not use a short boom log feed (as Cushcraft or Hy-Gain) with reflectors for 20/17/15 and a director for 10? 73, ... Joe Subich, W8IK/4 ex-AD8
Based on information that Roger Cox of HyGain has previously posted to the Towertalk group, putting the boom broadside to the wind is best of HF antennas. I'll attach the information below ... but a
Since you are quoting my post, don't leave out the important part. I posted Roger's listing of boom and element areas for a wide range of Hy-Gain antennas (from the smallest 3 element 10 meter monob
ON4UN uses a single elevated radial on 80 over his extensive non-resonant 160 meter radial system. Mose elevated radial systems seem to work better with a "choke 'balun'" to reduce ground currents o
Most people fail to realize that ON4UN's single elevated radial per element 80 meter four square is placed above his 160 meter ground plane. On page 9-40 of "Antennas and Techniques for Low Band DX-
will not look like hum bars. The DTV signal has a nearly flat "noise like" spectrum. Average DTV powers are substantially below the equivalent NTSC peak powers (at least 12 dB). Further, the separat
Broadcast/Cable channels 39 are different ... only channels 2-13 are the same. For Broadcast channels: F(l) = 470 + 6 * (14-N) For Cable channels: F(l) = 120 + 6 * (14-N) where 13 < N < 23 F(l) = 21
Was fairly common for me to find lose base (mounting) bolts on my T2X rotors back in the Columbus, OH area. QTH was on a flat land with a 200' drop off from southeast through north into a river vall