Hi Chad, A few dissipative ohms in the wrong place can make a big difference. Imagine a vertical loaded with a coax stub (one popular vertical does that, and advertises "no lossy traps"), or coax wou
....unless you are making impedance critical measurements and have a bunch of connectors in line. The very real bumps caused by the lower than 50 ohm impedance of the SO-239 are certainly not a prob
Hi George, It that a bandpass filter that rejects all frequencies above and below the operating frequency? One dB amounts to about 20% of applied power. At 1500 watts, filter dissipation would amount
Hi Lane, I use thin black nylon rope or very thick nylon twine. I find there isn't a whole lot of difference between it and special rope I pay bigger bucks for. The stuff I use doesn't stretch too ba
(grade, I get mine right from the hardware, I buy a hard grade stainless steel bolt. Bolt heads are marked with a stamped code that indicates hardness. Thread pitch is unimportant in this applicatio
Floyd, So far as I know, despite rumors, the co-users have ALWAYS been jointly responsible for lighting and maintenance. Section 17.4 is VERY plain about this, and to the best of my knowledge that ha
Even if you install it right side up, you will STILL have appreciable earth losses. The VERY strong electric field at the tips of the hanging elements will displace charges in the lossy ground, and
Hi Gerry, Your getting good advice on removing bolts, just be gentle and DON'T break a drill bit or easyout off in the bolt!!!! You haven't had trouble until you have a hardened steel toll broken off
Hi Dan, Great suggestion.....I would also worry about 120 vac running everywhere, especially outside around the antenna wiring. and do than I use a back connected diode across each coil to keep the f
Hi Barry, NEC doesn't consider many problems that affect us. 120 vac lines have a tendency to carry noise from things that spark and arc. They also carry garbage from switching supplies and digital d
Hi Gary, My experience with this comes from building race cars and high performance engines. When a $1.00 bolt failure costs 1/5th of a years income, a person learns what not to do. shop. I use "grea
writes: be a the nickel or for Most compounds are designed to work under a LOT of compression, not just a tiny bit. Thicker greases simply won't move out of the way easily, and you could compromise
The filter for out-of-band interference is now going into production at MFJ, a pilot run of 50 is complete. I have no idea of the cost, but the model is a MFJ-731, it's called a "SWR Analyzer filter"
I like Roy Lewallen's (W7EL) stuff, EZNEC and such. When I model antennas, I use Roy's stuff and I always find it comes out very close to the real world..within the limits of modeling. Roy is an ext
Hi Marty. This is a great reflector for antenna discussions, both the mechanics and electrical designs are covered by some serious antenna people. Claims about the feedline being an "effective vertic
Hi Bill, Pete and All. in I dislike the aluminum oxide problems. I avoid it for that reason. I've used #16 PVC insulated wire, brown or green. Hard to see and easy to splice, like N4KG I just tie it
None of these compounds, including those with metal, are "good" conductors. Two or two thousand pieces of metal, non-welded or soldered joints only make a conductive joint when considerable pressure
I respectfully disagree. help Sealing the joints could trap moisture if moisture migrates under the shrink from the inside of the tubing. The joint needs to be coated with enough goo to evenly cover
Hi Tom and all, Amazing as it seems, the size reduction results in almost no measurable performance loss except the (sometimes small) additional loss caused by increased current on the feedline. Ther
Hi Dave The reason this topic brings out conflicting opinions is almost certainly because of a lack of studies on multi-element array ground systems. That means the only response possible is conjectu