Howdy, TowerTalkians -- I'm researching temporary antenna installations (like Field Day) and was wondering if you have some input. What did you use? How did you erect it? Materials? Hints and kinks?
Good afternoon, My two cents are dedicated to the Optibeam. This past summer I installed the OB 12-4 at 90 ft on a Rohn 45 tower. I am a firm believer of " You get what you pay for ". And this is the
I have been using Tridon brand stainless steel hose clamps since the 70s. These are made in the usa. No lube was ever applied to any of them. http://www.idealclamps.com/catalog/clamps/catalog.php?sid
I find it amusing that the behemoth HDX-5106 is now rated at just 1 sq foot @ 90 mph. And thats with the ant no more than 1 foot above top of tower. I have the slightly shorter HDX-689. This is the o
I'm struggling with my remote control (aka "remote head") on my tower. I have yet to raise it and it's now a real issue. Here's the thing: I had carefully (or so I thought) wired from the tower to th
If the antenna has an impedance of 50 Ohms, and the coax is close to a quarter-wave or odd multiple long, you'll see an SWR(50) of 2.25:1 at the shack end instead of 1:1. 73, Steve G3TXQ Jim VE7RF __
Another point with respect to loss in that coax. Because its diameter is quite large, loss is MUCH lower than the RG8-size coax we usually use. It is also lower because the loss in ANY coax at HF is
Yes, let's do. That starts with studying and understanding the fundamentals of transmission lines and antennas, understanding that every design problem is different, and that one size does not fit a
A buddy of mine contacted m2 regarding the topic of placing all the weight onto the bearing inside the OR-2800. Interesting response from m2. Jim VE7RF ...............................................
A friend of mine asked Rohn about the tb3 and tb4 bearings. I had a pair of TB-4 bearings on my old tower setup. I now use peer brand bearings on the USt HDX-689..with locking collars. Jim VE7RF ....
US Tower HDX-689 Sheave replacement The UST HD-689 uses aprx 22 pulleys in total. All are aluminum, with an internal bearing. If the bearing is trashed, the soft aluminum pulley is probably trashed t
Have you tried squirting it with WD-40 or a similar elixir to see if you can free it up? Worked for me. After the WD-40, I applied regular oil to it. Rick N6RK Jim VE7RF _____________________________
This may have been mentioned before. Buy 3 x identical digital torpedo levels..cheap at sears etc. They are aprx 8-10 inchs long..and are magnetic down one or both sides. They not only have the norma
Steve, Thanks for your response. I am not planning on buying them but sitting with 3 controllers, so I thought I could at the least recover some use out of them. I agree, the Green Heron controllers
Hi Dan How lossy are traps really? I have seen so many diffrent figures on how bad they are or aren't 73 John AF5CC w out on cw. A buddy had a TA-33 jr... thay went screwy one day..so we took it down
My 86 or 89 foot crank-up tower project seems to be progressing through my County review boards. So now I am getting really excited for my first tower. on a 15 mast will DECREASE the windload rating
For the same reason, the use of SEPARATE grounds for RF or for audio with no "green wire" between the equipment is VERY unsafe -- the reason for the safety ground is to blow a fuse if something "brea
Even with a perfect 50 Ohm antenna, there can be significant coax braid current and stress on any balun that is installed! With a perfect 50 Ohm antenna, at the 1500W level the differential-mode feed
If the choke is primarily reactive, and the coax braid impedance is also reactive but the opposite sign, adding the choke may *reduce* the net CM path impedance and *increase* the braid current. Maki