Ive got a question about hooking up an Antenna Supermarket Eavesdropper T with a 72ohm balanced feedline to my Kenwood RX. My Kenwood R-1000 rx has a coax connector and 3 wire connections labeled MW ANT, GND, SW B. When I hook up my feedline do I plug one end into SW B and the other into GND? If so where do I ground the receiver then? Can I ground the RX via the coax connector or do I connect both the ground and the other side of the feedline in GND? Im all confused. Can anyone straighten me back out? Thanks.:headbang
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Kenwood R-1000 antenna question
- Thread starter KC8LWG
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The coax connector is actually the SW-a antenna connection and the spring clip connector is SW-b connection. There is also the MW ant connection as you have noted. The MW antenna connection is only active on 2MHz and below. Typically yopu would use a long wire connected to it and a ground wire connected to the GND connection. The same is true for the SW-b antenna connection while the SW-a uses regular coax connection.None of these antenna connections is meant to be used with a balanced feedline HOWEVER since we are just talking about a receiver it really will not make that much differance if you unbalance the system by connecting one side of the feedline to ground. Simply connect one side of the fedline to the GND terminal and the other to the SW-b terminal. If you wanted to be a purist you could add a 1:1 balun to convert the balanced feedline to unbalanced and use the coax terminal connector but for receive purposes it will not hurt a thing and performance will still be good.
Forgot to add that the GND connection simply goes to the chassis ground so it is common to the coax ground connection as well as the entire chassis. There is a little trick that can be done if you are handy. The SW-b connection has a small RF transformer on it inside the radio labeled T1. You can lift the ground side of it and connect it to the GND terminal and lift the ground connection that is presently on the GND terminal and connect it to a conveinient ground location.This would convert the SW-b and the GND terminals into a balanced input. I have done this before but this advise is given on a "you do so at your own risk" basis. You will not harm the radio by doing this but if you miswire something your reception may suffer but that is all.
BTW nice older receiver. I have had one since 1985 and will never part with it.
Forgot to add that the GND connection simply goes to the chassis ground so it is common to the coax ground connection as well as the entire chassis. There is a little trick that can be done if you are handy. The SW-b connection has a small RF transformer on it inside the radio labeled T1. You can lift the ground side of it and connect it to the GND terminal and lift the ground connection that is presently on the GND terminal and connect it to a conveinient ground location.This would convert the SW-b and the GND terminals into a balanced input. I have done this before but this advise is given on a "you do so at your own risk" basis. You will not harm the radio by doing this but if you miswire something your reception may suffer but that is all.
BTW nice older receiver. I have had one since 1985 and will never part with it.
Ah that makes more sense now. Thank you. Maybe a different antenna is in order? The instructions also say that you can solder a PL-259 to the end and use it that way. Maybe thats what I should do. What do you think? I want to make sure im getting the most out of my setup even if it costs me a little more money.
"Impedance to Receiver: 50-75 ohms balanced. The Eavesdropper/t may also be very effectively operated as an unbalanced antenna by installing a co-axial plug on the feedline."
"Impedance to Receiver: 50-75 ohms balanced. The Eavesdropper/t may also be very effectively operated as an unbalanced antenna by installing a co-axial plug on the feedline."
OK, when they say that it can operate as an unbalanced antenna by installing the PL-259 connector that accomplishes the same thing as using the SW-b and GND connector as it is wired from the factory. In fact it is the EXACT same thing. It's a pain wiring twin lead to a coaxial connector so just use the spring clip wire terminals on the back.It does not matter which wire goes into which hole.this way you can pull one side out of the SW-b connector and insert it into the MW connection for AM broadcast and 160m listening.
Would another antenna be worth looking into? Ive heard good things about this...Par Electronics EF-SWL End Fed Dipole SWL Antenna. Par EF-SWL.
I'll be perfectly honest with you. I have been an amateur for about 20 years and have never and will never buy a wire antenna ESPECIALLY one for a receiver. IMO they are not worth the money or even the shipping costs alone. For a few dollars I can throw up a hundred feet or so of wire and have just as good performance. I currently have a 300 foot long wire from the tower sloping down to about 7 feet off the ground and it works GREAT on all bands. I even use it for TX'ing on 80m and 160m sometimes.There are times when it pays to purchase antennas such as beams etc but for simple wire antennas especially RX only antennas it is very hard to beat a simple wire as long and as high as you can get it.
There's no such thing as an "end-fed dipole"; this is antenna hype at its worst.
LOL, I missed the word "dipole". I thought the Par Electronics antenna was a simple end fed wire antenna. That will teach me to actually click on the link next time. LOL
LOL, I missed the word "dipole". I thought the Par Electronics antenna was a simple end fed wire antenna. That will teach me to actually click on the link next time. LOL
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Ummmm...... that was freaky. Somehow when I was quoting part of Beetle's post and adding my own comments it appeared as if my post was done by Beetle. Oh well there have been some things going on around here that required the forum to be shut down for a little bit and it happened around the time I posted so I guess there was a little glitch in the system. Don't worry Beetle I haven't hacked your user account. (yet) 
I was looking all around for my first post -- it's gone!
One other thing I said was that the "best" antenna for HF SWLing would be a 50 element log-periodic with a 300 foot boom on a 500 foot tower (rotating tower, of course). But in the realm of reality, a 50 to 100 foot wire up as high as you can get it, in the clear, will work wonderfully.
One other thing I said was that the "best" antenna for HF SWLing would be a 50 element log-periodic with a 300 foot boom on a 500 foot tower (rotating tower, of course). But in the realm of reality, a 50 to 100 foot wire up as high as you can get it, in the clear, will work wonderfully.
Sorry about that Beetle. I was just as surprised as you were about that one. I have no idea what happened when I quoted your post and added my own comments. When I hit "submit reply" it looked as if you had made the post that I intended to make and your original was gone. Must have been a gremlin is all I can say.
i have a 125foot long wire about 45 feet in the air (as a flattop) that works well for general shortwave listening but i find myself using my (homebrew) G5RV more often lately....
it works GREAT with the gen coverage receive in my ts-940
another one that works VERY well (and puts an awful lot of wire in the air) is the "cobra antenna" found here http://www.nonstopsystems.com/radio/frank_radio_cobra.pdf
can be built for 30 dollars or so
the antenna you have should do just fine hooked up as everybody else has suggsed........maybe think about a tuner if you really have some extra cash burning a hole in your pocket
scott
it works GREAT with the gen coverage receive in my ts-940
another one that works VERY well (and puts an awful lot of wire in the air) is the "cobra antenna" found here http://www.nonstopsystems.com/radio/frank_radio_cobra.pdf
can be built for 30 dollars or so
the antenna you have should do just fine hooked up as everybody else has suggsed........maybe think about a tuner if you really have some extra cash burning a hole in your pocket
scott