If you open the tx antenna feedline for rx, from my experience, you need to completely open the entire feedline, namely the coaxial cable shield as well as the center conductor. coaxial relays that m
Actually, if you have a quarter wave driven element and you are disconnecting it at the feedpoint, your relay concern shouldn't be voltage so much as current. Fast switching and large contact surface
Interesting information here: http://www.arrl.org/files/file/Antenna%20Book%20Supplemental%20Files/22nd%20Edition/Seawater%20Grounds%20-%20by%20N6LF.pdf Rob K5UJ _________________ Searchable Archives
Some may say this is nit picking but to me it is important: MOST of those so called modes listed are NOT different modes of transmission, they are digital protocols. A mode of transmission is a meth
Oh boy, here we go again. As I believe I have pointed out before, your QTH is not that far from a fairly vast amount of salt water. You can believe anything you want, but your experience if not embe
My opinion: the PCB scare is overblown, just like lead in paint, asbestos, etc. If you are intelligent about it, taking prudent precautions, PCB in caps and dummy loads should be fine. I'm sure hand
It's a legitimate idea and probably one of the best ways of dealing with the problem when you think about what can and can't be controlled. I've been seriously suggesting the power limit be raised o
Last year I purchased an Airspy HF+ Discovery SD receiver. Eventually I got around to trying to use it with a second hand Windows laptop. I was concerned about blowing out the front end on transmit b
It is indeed true that variations in liquid soil moisture will dramatically affect ground system performance and base fed vertical impedance when an on, or below grade ground system is used. Frozen g
Most AM plants have been where they are for decades. I remember being at the local 670 site several years ago. That tx site has been there since the 1930s. This is a ~800 foot tower, now with two sig
""A more reliable approach is a tuner in your shack. The extra coax cable loss from elevated VSWR is insignificant on topband."" We don't really have enough information to make that claim. First, you
For 160 m. frequencies, connectors on hardline that preserve the geometry (Z) of the line aren't needed. You can dress the line (i.e. strip back the jacket and dielectric) and make connections to tra
I'm not following the reasoning here. How are listeners never fighting noise below 1710 kc? In some cases noise (or by noise are we thinking of QRM?) is worse on medium wave broadcast channels becau
Tnx for clarification. Hi, I guess I was thinking of RFI from appliances and arcing contacts on power lines. 73 Rob K5UJ _________________ Searchable Archives: http://www.contesting.com/_topband - To
Seems to me that for the money hams pay Flex in that annual service fee, (or is it monthly?) you ought to get professional Windows maintenance. There are ex-MS techs out there who can be hired. I've
The proper way to use a tower like yours as a base excited monopole is to construct a pier of concrete with a bottom plate pin bowl that is steel and bonded to copper strap that goes down on each of
If you want to find out about QRN somewhere you don't have to ask on an email list. You can just go to windy.com or www.lightningmaps.org and see for yourself. Also lightningmaps has a gray line plot
Scroll down to drawing 5 and 6 to see the proper way of handing intersecting radials. http://www.hatdaw.com/papers/groundsystem.pdf 73 Rob K5UJ _________________ Searchable Archives: http://www.conte
We all learn this sooner or later: Don't use ferrous metals to conduct RF. If a metal fails the magnet test, it's out. Every time I get some item of homebrew or something that's had a previous owner,