HFU HF Underground
Technical Topics => Equipment => Topic started by: ChrisSmolinski on November 03, 2021, 1200 UTC
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Well worth reading, this article describes how a Beverage antenna actually works, which is very useful if you decide to build one. I have two here, a 500 ft aimed northeast to Europe, and an unterminated 400 ft aimed south, which also works well due north. I leave it un-terminated specifically to listen to an otherwise weak pirate / part 15 station on 1620 kHz :)
http://www.arrl.org/files/file/QST/This%20Month%20in%20QST/2021/11%20November%202021/Silver%20Donovan.pdf
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The beverage can be a great traveling wave antenna, and agreed, even as just basically an unterminated wire on the ground.
I used to have an 148' unterminated beverage-on-ground pointing vaguely NW/SE. It was good for monitoring continental NA amateur comms on 80m through 20m, and decent off the other end for listening to MW to mid-HF Caribbean broadcast stations.
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Yeah. definitely have plans for one. Just hope I can get it pointed in a good direction. A lot of people use them for the receive on 80/160 receive set-up's. and transmit on a different antenna. I gotta admit though, don't you need as much of a good antenna to transmit back though? Providing they're not using such a great receive antenna?
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Often the idea on the lower bands is to optimize the receive signal-to-noise ratio due to higher noise profiles at lower frequencies. The idea is regardless of whatever other operators are using, you can not work them if you can not hear them. ;)
You have the scenario right. Many HF ops use a vertical or inverted-L to transmit and a beverage or similar directional SNR-optimized antenna system for receive on the low-HF bands. Verticals can be great for transmitting DX on 160 and 80, but sometimes quite noisy on receive, especially is subjected to nearby manmade RFI.
Regardless of band, think about how many comparatively low-power and/or antenna-limited stations often can work much larger stations having stacked beams, curtain arrays, multiple beverages, etc. The smaller stations are relying on the larger stations to do most of the so-called "heavy lifting" for both transmit and receive.
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I gotta admit though, don't you need as much of a good antenna to transmit back though? Providing they're not using such a great receive antenna?
Beverages are for receiving and not, IIRC, for transmitting.
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I gotta admit though, don't you need as much of a good antenna to transmit back though? Providing they're not using such a great receive antenna?
Beverages are for receiving and not, IIRC, for transmitting.
Definately not for transmitting with.
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AFAIK, it has been done for experimetation, but yeah, much of the power is going to end up in the terminating resistor as heat. o.0
Remove the terminating resistor, and a beverage is little more than a low longwire, which is another type of travelling wave antenna if long enough.
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Hey All
I've read a good bit about Harold Beverage,a fascinating man.
FWIW, Many years ago I laid 2000 ft of single conductor field telephone wire from tree to tree down to the swamp where I could vary the resistance feeding the gnd rod.
I fooled around by sending audio from the receiver down the antenna via a cheap 49 Mhz transmitter loosely coupled to the antenna . It allowed me to make some seeming "adjustments" by placing my hand held scanner near the wire and varying the resistance in the swamp.
I was pretty green re radio knowledge then . In retrospect not really definitive as to what was actually going on re "adjustments " , but fun to play with . One heck of an antenna and no problems despite being line of sight to monster WRKO at one mile. Lots of LW b'casts and sferic fun .
Once I inadvertently got a good zap by induced lightning current from a storm around 4 miles ( moving away). Stupid. Dangerous. Interesting.
Ah , youth.
K
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Hey All
I've read a good bit about Harold Beverage,a fascinating man.
FWIW, Many years ago I laid 2000 ft of single conductor field telephone wire from tree to tree down to the swamp where I could vary the resistance feeding the gnd rod.
I fooled around by sending audio from the receiver down the antenna via a cheap 49 Mhz transmitter loosely coupled to the antenna . It allowed me to make some seeming "adjustments" by placing my hand held scanner near the wire and varying the resistance in the swamp.
I was pretty green re radio knowledge then . In retrospect not really definitive as to what was actually going on re "adjustments " , but fun to play with . One heck of an antenna and no problems despite being line of sight to monster WRKO at one mile. Lots of LW b'casts and sferic fun .
Once I inadvertently got a good zap by induced lightning current from a storm around 4 miles ( moving away). Stupid. Dangerous. Interesting.
Ah , youth.
K
Regarding zaps someone I know runs a lot of bevs and he regularly replaces terminating resistors, I suggested bypass them with a gas discharge or neon bulb and using higher wattage resistors and see how it fares. That reduced the replacements but for the closest and strongest of zaps.