Can someone show me how to hook up an FM antenna? Please!

nickrobotron

una bella tazza di caffe
Right now I just have a piece of speaker wire stuck to the back of my receiver and it helped reception, but it still sucks. I don't listen to FM, that's why I'm just now asking. I would like to start listening to more of it though. So can someone take a snap shot of the back of their receiver or just carefully explain it to me? Thanks!
 
It's not my tuner, I found the pic online but, look for those screws. You have a common and a choice of 75 or 300 ohm.

If you are settled on speaker wire (not the best pick) hook one end to the common, the other to 300 Ohm.
I dipole anttenna is a better pick, same hook up. It's that "T" shaped wire thing you can by at Home Depota/Fleet Farm/Radio Shack/and so on.
the 75 ohm is your using coax for your antenna wire.
Best bet, a rooftop antenna, let us know when your ready to make that move.
 

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So, waddaya got back there?

An "F" connector, like they use on cable TV? That's for a 75 ohm lead. You simply screw the antenna lead into this.

Or perhaps a couple of screw terminals? These are for 300 ohm "flat" lead, which is rarely used anymore. You would connect one side of the lead to one terminal and the other side to the other.

You can buy cheap adapters to convert either one to the other depending on your needs.

But, sometimes punting* works just as well when one doesn't have a proper antenna.

But, before flogging yourself with that lone wire, you should at least try one of those $3.00, 300 omm "T" antennas that RatShack sells. If you're in a decent area it should help but don't be surprised if you need more of an antenna to get some decent performance.

Poke around this site. It can be very helpful for FM issues. http://www.radio-locator.com/

*this would mean just taking any wire and connecting it to any antenna terminal and, moving it around, and hoping for the best. All I have on my CSW Model 88 is a single wire sticking into the middle of the "F" connector.
 
An older unit will likely have 3 terminals...one marked ground or "gnd", and two marked "ant" or 300 ohm. (with the upside-down U symbol for ohm, possibly?) One of the 300 ohm teminals may also be marked 75 ohm, with a line or some sort of marking "linking" it to the ground terminal. The ordinary cheap "T" FM antenna would connect to the 2 terminals marked 300 ohm. Your speaker wire might make do til you can scrounge or buy a "T" antenna. (they're cheap. Just take a 6 foot length or so and separate one end of it so the two ends are 30-36" apart when spread out to the shape of a "T". Separate the opposite end a few inches, strip the ends and attach to the 300 ohm terminals. Try orienting the "T" in different directions for best signal. Should coaxial cable be involved...you can either connect the center conductor to the terminal marked "75 ohm" and the shield to the ground terminal. Most amplified FM antennas have a coaxial cable with an "F" type connnector (same as cable TV) at the end. Some receivers have a "F" jack on the back for FM, so it's just plug 'n play. Otherwise, to eliminate the need to cut the connector off, strip the cable, etc., just get a cheap 75 to 300 ohm matching transformer...screw the cable to its jack and connect the twinlead that comes out of the transformer to the 300 ohm terminals. Matching transformers are 2-2 1/2" long and about 1/2" in diameter with an "F" screw-type jack on one end and a short lenght of twinlead coming out the other. Cheap and easy to find at Lowe's, Home Depot...heck, even Radio Shack might still stock them! :) Plus, there's a good chance they'll carry a pre-made "T" type antenna for a couple bucks that'll perform a little better than a homebrew job made from speaker wire. If it's an outdoor antenna you desire, if an FM-specific antenna isn't readily available, an inexpensive outdoor TV antenna will do the job. They can also be mounted in the attic or the top of a closet if outdoor mounting isn't feasible. Twinlead feedline can be used, or 75 ohm coax (RG-59U) with matching transformers at each end.
Hope I was helpful!!
 
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On the two terminals on the left... they are labeled 300 ohms. This is for twin lead, regular old fashioned twinlead TV antenna wire.

The 2nd and 3rd terminals from the left are labeled 75 ohm and Ground. This is for coax. The middle lead of the coax goes to the 2nd terminal from the left, and the coax shield goes to the 3rd terminal, which is chassis ground.

AM loop antennas, and that type is the only practical type for AM reception, connect to ground the AM, which is the terminal on the far right of that antenna terminal group.

Your exact connections may be positioned differently, but marked the same.

Some receivers have F-connectors, threadded connectors like on cable TV, which is 75 ohm.

If your receiver does not have connections for 75 ohm, but you have cable coming in from the antenna, then connect a balun aka transformer to the end of the cable. This is a small cylindrical device with the threaded F-connector on one end, and two 300 ohm leads on the other, usually with spade lugs. Connect the spade lugs to the 300 ohm terminals on your receiver or tuner, and screw your incoming cable to the other end of the transformer.
 
I'm following this thread with interest. I hope no one thinks this is a hijack, I believe this is along the same lines as the poster. This is what I have. Home made dipole FM antenna mounted 40 feet above the ground. It's made with speaker wire wrapped around a 1" dia. 10' long plastic (PVC) conduit. I soldered a 75 to 300 ohm transformer to the speaker wire. Insulated it and connected to RG-6 cable and ran it inside the house. At my receiver I again used a 75 to 300 ohm transformer to bring the connection back to two wires with forked connectors and used the two screws on the back of the tuner to connect the antenna up. I get lots of stations except one at 104.1 out of Evansville, IN less than 30 miles away. I get it on a boom box, my truck, etc. I get several stations above 104.1. The question is, am I harming my reception by having two transformers in line? I looked on line for an F connector with two wires only. None found. I'm going to try a Radio Shack Cat. no. 278-201 chassis mount coaxial socket to try to fashion a cable to two wire conversion. Any thoughts on this? If this post is out of line here I apologize and will remove it to another place. Fritz
 
Their will be some insertion loss from any transformer.

Have you tried this? It screws right to the end of any F connector equipped RG type cable.

Radio Shack Part Number 15-1230, $6.29

The price is rather high as they can be had for $2 to $3 elsewhere.
 
You've been following this thread for over 6 years?

Hehe. Just kidding.

I would just try the dipole (the "T" shaped antenna) hooked to the 300 ohm terminals on your receiver. It doesn't sound like you actually have a dipole with wire just wrapped around a plastic tube.

Doug
 
I've had good luck with "rabbit ears" as well. Not fancy, but easier to move around than the "T" if the T isn't pointing the right way when tacked to the wall you might have to use.
 
Interesting, nickrobotron still hangs out here, so I'm wondering how often he finds himself listening to FM these days? I do, sometimes, but MOG sharply curtailed the already relatively small amount of radio via the home system.

If he does still use FM occasionally, what did you do about an antenna, nick?
 
I'm following this thread with interest. I hope no one thinks this is a hijack, I believe this is along the same lines as the poster. This is what I have. Home made dipole FM antenna mounted 40 feet above the ground. It's made with speaker wire wrapped around a 1" dia. 10' long plastic (PVC) conduit. I soldered a 75 to 300 ohm transformer to the speaker wire. Insulated it and connected to RG-6 cable and ran it inside the house. At my receiver I again used a 75 to 300 ohm transformer to bring the connection back to two wires with forked connectors and used the two screws on the back of the tuner to connect the antenna up. I get lots of stations except one at 104.1 out of Evansville, IN less than 30 miles away. I get it on a boom box, my truck, etc. I get several stations above 104.1. The question is, am I harming my reception by having two transformers in line? I looked on line for an F connector with two wires only. None found. I'm going to try a Radio Shack Cat. no. 278-201 chassis mount coaxial socket to try to fashion a cable to two wire conversion. Any thoughts on this? If this post is out of line here I apologize and will remove it to another place. Fritz

Radio Shack sells 300oHm antenna cable still. It's either 50 or 100ft for like $18.00. Why not make a proper 300oHm T Dipole and connect it up in place of the speaker wire, balun,cable, balun affair you have now.

Some antenna's (especially the "T" Dipole) are directional. I think you'll find if you rotate that affair you have, you'll probably pick up that one station you can't get on it now.

6ft cross piece. Connect the ends together. In the middle, cut one side, but not all the way thru, strip back and connect (solder) the leads to the down wire. Then attach two U lugs and connect to your stereo.

I find I get better reception with 300oHm twinlead than with cable to my VHF/UHF/FM antenna on the roof.
 
I like old TV rabbit ears. Easy to find at garage sales. The newer TVs came with rabbit ears with just a small plastic post meant to stick into a hole on the molded plastic rear of the set, if you were going to use it. I make a wood block with a hole in it to set it in.
 
Kenwood and Pioneer are at fault. If the stereo won't work, it could mean their tuners need realigned. Not easy for a non-professional to do. In the mean time, when tuning a strong station try sneaking up to it. In other words, very slowing tune it to get the stereo light to work. That little trick may or may not work.
 
From your picture it appears that you have a 300 Ohm flat twin lead attachment from your antenna. That the signal strength meter is reading high with no stereo suggests the problem is in your receivers.
 
The Pioneer (SX-450) has a center channel tuning indicator but no signal strength. Adjust the tuning to get the meter centered. In the photograph the stereo and power indicators appear to be illuminated.

I can't tell what model the Kenwood is.
 
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