Another good grid dipper was made by B&W. Mine has been operating for many years. Maybe it's 35 or 40? It covers 1.7 to 260 MHz and uses a 955 acorn tube for the oscillator. The tube may be expensive
RG-213 costs $0.33 per foot these days. The bandpass filters out there for amateur use give a max of 45 to 50 dB isolation and not even that much between adjacent bands, You cannot transmit at the K
measure about Irrigation TUBING is 4 inches OD with about 0.058 wall. Irrigation PIPE would be 4 1/2 OD, but I've never seen any. George W2VJN -- FAQ on WWW: http://www.contesting.com/towertalkfaq.h
International Radio and Top Ten Devices will have booths 702 and 703 this year. Come by and say hello. George W2VJN -- FAQ on WWW: http://www.contesting.com/towertalkfaq.html Submissions: towertalk@c
The mechanical handbooks say that the rope needs to rated for the full load. Under static conditions there is no problem, but dynamically the full load could be applied to the rope. Also, it's the s
These comments are in the archive somewhere, but since the subject is here again, I'll repeat them. In 1966 I put up 80 feet of #25 to factory specs with a 4 element 20 on top. Initially the guys wer
Regardless insulator high-impedance maximize any tend to be guy wires Whether it results in a high impedance or not depends not only on the insulator or lack of, but on how high the tower is and how
more These boxes are cheaper than buying a blank Bud box and they already have the DB connector holes in them. See the web site for Computergate.com. The connectors have long leads on them and may b
Fred, The same discussion appears in the Television Engineering Handbook edited by Fink. I quote: "For visual acuity tests of the type described, normal vision, corresponding to a Snellen 20/20 ratin
I have made well over 100 stubs of various kinds and with several types of coax and would like to offer some real numbers measured with a network analyzer. First of all, a stub cut for the CW end of
In using YT to try and determine the best separation for a pair of 40 meter beams and my terrain, the following happened: I started with a spacing of 100 feet and gradually raised the bottom antenna
Here are some measured numbers for the subject of this discussion. Loss through the Top Ten A/B relay box at 28 MHz is 0.02 dB. The path through it includes 2 SO239s and 2 relay contacts. Losses thro
I have noticed that the attenuation peak moves around several dB in shorted stubs made from LMR400 when it's flexed. It must have something to do with the aluminum shield moving. There was no problem
"Stuff works fine with legal power. It comes in a tube and it gets squited into the female connector. When the connector is full, it can't absorb any water. George W2VJN -- FAQ on WWW: http://www.con
If there is concern about a thrust bearing failure, why not eliminate the unit from the top plate and replace it with a lateral bearing. This should reduce the possibility of failure to near zero. Th
About 1965, long before we had computer modelling, I got to thinking about tilting the boom of a Yagi to lower or raise the elevation angle of radiation. This would be really neat for switching from
My X9 is 14 feet under a 40-2CD and I can offer some observations as well. The vswr at 7.0 is 3:1. It nulls to 1:1 at 7.8 MHz. It has many nulls between 7 and 14 MHz that go down to 1.2 or so. As a r
in As we found out with the X9, which uses the same boom to mast arrangement, it would be better to completely assemble it on the ground and just insert the mast U bolts on the tower. The "cradle" i
My 40-2CD is 14 feet over an X9 and is 165 feet above ground. Here is the vswr measurements. It was set to the CW measurements. 7000 1.2 7020 1.1 7050 1.15 7075 1.2 7100 1.35 7150 1.65 7200 2.0 Georg
To set a starting reference in case of future problems, I have just measured the cable losses on a new tower installation. The cable lengths are all 360 feet from shack to tower and have no switches