I did some quick NEC-2 simulations to determine the gain and take-off angle of K9LTN's impressive array. Not knowing his exact dimensions, I used 45' vertical spacing and 55' horizontal spacing, with
My simulations indicate that as you adjust the array elevation above 5 degrees the vertical lobe begins to broaden. At about 16 degrees elevation, the vertical 3 db beamwidth is 24 degrees (from 3 to
Jim, I'm tilting the entire array in my simulation. I forgot to mention in my earlier email I'm simulating the array on 20M. At 0 degrees elevation or tilt (E) the vertical beamwidth (VB) is 5.4 degr
Making the 1-1/8" in tubes shorter and the 7/8" tube longer will increase your resonant frequency. However since you're only talking 1" change on both elements. the effect will be minimal. Just for f
I have used 3000' of the Synthetic Textiles rope to hang antennas in trees. Instead of pulleys, I use ceramic electrical insulators (the kind with integrated lag bolt) up in the tree and then run th
I'm not going over a tree branch. I'm going through they eye of a ceramic insulator. The ceramic insulators I use are very smooth. The real point is that 3/8" nylon rope outlasts the 3/16" dacron/po
about get The answer depends on what you're using now and what your other possibilities are. For some interesting reading on low-band antennas see: www.w8ji.com/receiving.htm www.w8ji.com/receiving_
It seems like the answer is dependent on why the guys are different lengths. His lot isn't level, so he may have to go further out because the lot is sloping away in one direction (to maintain the s
Chances are the impedance match will be poor if you try to use the D4 as the DE on your A3S. The D4 is designed to give an impedance of ~50 ohms with no parasitic elements. Add a reflector and direc
I have an 8 KW unit that is permanently installed and runs on natural gas. It isn't obvious when you first look at them but they will not work with the standard gas meter/regulator which only suppli
Ameritron in their RCS-10 remote coax switch use Potter and Brumfield RTD 14012F 12 volt at 16A/240v relays. What is a good choice of relay for RF switching in homebrewed antenna selectors and so for
Hi Ed, I've done a lot of models for the folks at SteppIR and have done extensive modeling of stacked SteppIRs. I think you may be disappointed with your current plan. My models show that 4 over 3 S
Jon, Mike has mentioned your A4S vs SteppIR S/N situation and we were both baffled. I think the description of your antenna farm has probably answered the question. Having a 402CD 14' above the Step
The compressive strength of concrete is always based on 28 days of curing time. If you specify 3500 PSI concrete, it will take 28 days of curing to reach that strength. After 28 days, it will contin
I've been using a simple method for years. I read the legal description of my property. Based on that I have a very accurate bearing for each of my property lines. My house is quite accurately lined
Washington State has adopted the International Building Code (IBC) and it appears that many other states are doing likewise. I looked at the windspeed charts that accompany the new code and, if I'm
-- Original Message -- Do tower manufactures like US Tower rate their towers based on the 3-second gust, 10-minute average or hourly mean? I don't think I've ever seen a tower spec that indicated whi
If he only uses on side of the array, he has a 4/4/4 stack, not an uncommon operating setup. Then if he's trying to copy a marginal signal he can add the other side to improve the signal. If I had t
I'll be putting up my new SteppIR soon and had to make the same choice for my 250' coax run. Using the coax loss calculator at: www.ocarc.ca/coax.htm I get the following at 50 MHz for a 300' run of
I mounted a Cushcraft A3 (with 40M dipole) using a Ham-IV rotator at 95' on a Douglas Fir tree that was topped by the previous owner. That was in 1984 and everything is still working ok. The only ma