I had a core crack once due to overheating. It was in a "2KW" 4:1 balun. It didn't care for the particular impedance my zepp presented on 75 meters. I guess I should have saved the two pieces and use
I run into W6VPH in the hallway at work from time to time. He has a picture of that 13 element array above his desk at work and his eyes really light up when he describes the performance. The array w
I think this topic would be fair game for CQ-Contest (I have seen it discussed there before). While the general topic of computer networks is a bit off the mark, the specific issue of RFI susceptibil
Yes, agreed, but the stack has a wider elevation coverage in the sense that you can quickly change configuration (U/L/BIP/BOP). With the single long boom yagi, you can only adjust azimuth, the elevat
Jon, Your are quite correct about the rotator mounting, John. If you cut just one of the Z-braces in a standard straight section, however, you can actually get a rotator as big as an Orion OR-2800 in
Hi Chuck, The problem with antenna tuner specs is that they don't include qualifications about the power rating versus degree of mismatch. Another problem that was not addressed in the ARRL comparis
That's a great suggestion, Eric. Too bad the MFJ-269 that I have doesn't have the graphical display. I am sure that really speeds up the process. Actually, the ARRL lab probably has an HP network ana
it. That is the article we were talking about, Joe. My concern was that the sidebar in the article only discussed how the efficiency measurements were made. It did not mention how the antenna the tu
Hey wait a minute, Ward, my posting you snipped was to Topband not Towertalk.You are getting me all confused :) Yes you are correct, that is a danger with back-to-back diodes. In our case we were doi
Actually you could make the inner tube as long as you want and it won't make any difference as there is nothing to excite the capacitor formed by the concentric tubes. The end where this coaxial capa
I would put a choke balun (coax wound into coil) between the point where the coax leaves the boom and starts down the mast and then ground the coax shield to the mast on the transmitter (shack) side
I recall using Methylene Chloride a number of years ago for this purpose, but I noticed recently that its been banned (at least a my workplace). Mike, W4EF............................................
machining it. People working in plants where it is made (Brush-Wellman) have been reported to have health problems as the result of industrial exposure (there was a story on 60 minutes a few years a
larger Don't to to I am not a metallurgist, but I would be careful about getting the tubing too hot as you might weaken the alloy (others more knowledgeable in this area might want to comment). I wo
Hi Michael, My friend John in Thousand Oaks, California had a similar situation. His neighborhood had CCRs, but the HOA had dissolved many years prior to his application for a conditional use permit
Dan, Check out Florida RF labs: http://www.rflabs.com/ They should have something that will work for you. Looks like the loss will be somewhere between 1 to 4dB at 5.8 GHz depending on how much money
The tension on the live side in constant all the way down to the thimble where it is transferred into the next segment (the eye of a turnbuckle for instance). While the dead-end of the guy cable near
As I understand it, the reason that the quad was implemented at HCJB was to eliminate the coronal discharge that they were suffering on their 1/2 wave elements. Apparently this was a big problem at t
You can actually model the conductor losses in a Yagi (or quad for that matter) using NEC. You will find that the difference between aluminum tubing and a perfect conductor is typically a very small
results to. Yuri, I am curious. Have you ever compared your single band scores with the equivalent W2PV band scores with and without all of those 2 point W's removed from your score? Did you ever go