FM antenna-gctid402898

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I have the stock FM radio in my '86, I know, but music isn't that important while fishing. But my daughters think it is.

One of the speaker wires had fallen off. But my daughter with her skinny arms was able to fish it out and we now have two speakers again. Small victories.

Did they put any form of antenna on these radios? I don't see anything. Reception is soso.

Thanks

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My 88 had a single wire connected to the connector. I've seen splitters on the vhf antenna cable.

[Jeffw Guru Find all posts View Profile Close Jeffw]

I'm currently using that splitter, it greatly improved FM reception, but possibly at the expense of UHF reception. I plan to take the splitter out of the loop and check again. Stay tuned...

Meanwhile, a rubber ducky am-fm antenna is only $10-20...

[talman Founding Member Find all posts View Profile Close talman]

Broke down and bought an antenna meant for it's use.

http://www.ebay.com/itm/Shakespeare-...item231ff1c67d

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So I found a small white wire coming out of the radio which must be what they figured would work as the antenna. But the connection at the radio appears to not have threads on it. So how would the antenna be connected?

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Does your boat have rails? If so, that white wire may have originally connected to a bolt at the base of one of them. May even be connected to the aluminum rub rail at some point. I have a white wire that disappears forward into the dark and no dedicated FM antenna, so I suspect that is where it goes. Never had to look, because my FM works fine.

[captharv Founding Member Find all posts View Profile Close captharv]

A word about splitters. They are a big compromize on performance.

First lets discuss antennas. The AM-FM to VHF radio splitter gets a lot of press, both good and bad. Mostly bad. If the splitter goes bad, goodby both the VHF and sterio. The front end of the radio is not made to take 25 watts, and the VHF transmitter does not like a bad SWR. Hopefully, its protection circuitry will shut down teh transmitter in time. This part is a biggie: The VHF marine radio is a life saving device. I will not attach anything to it which MAY deter performance.

Next the actual antenna. A VHF antenna is designed to work between 156 and 162 MHZ. It "resonates" there. However, the main point is resonance means ability to transfer the radiated energy down the cable to the radio. This antenna while being fine for the VHF radio, is way out of resonance on FM broadcast, and exgtremely way out at the 1 MHz broadcast AM frequencies. Basically put, it is a poor receptor at anything except VHF.

Next the actual spltter uses circuitry to separate teh signals into their respective ports. The transfer is NOT 100% and more loss is added.

All that said, the splitter will work somewhat if you are relatively near the transmitters. For going out offshore 20-30 miles like we do when we fish, a separate antenna for each function is the only way to go.

The Bayliner boats have a 31" piece of wire hanging out the back of the stereo as an antenna. It works somewhat, but will not pull in the distant stations.

Let me cite an example. Orlando had a popular oldies station I liked. We go to SIlver Glen, which is surrounded by 100' high trees. ALL reception is very weak. SIlver Glen is aproximately 40 miles from the center of Orlando. So, reception is easy? Not! The sattions transmitting site is in Bithlo, Fl about 18 Miles from te center of Orl, and just about the other direction. Now we are talking about 60 miles (+/-) and having the trees. I installed a real antenna, and put a ground wire from it to the boats wiring. Pulls in the oldies station.

Us radio engineers have always said that any receiver (or transmitter) is limited by its antenna.it has to grab that radiated energy and translate it into electronic energy, and only than, can the radio process it.

Shakesphere makes a 4' AM-FM antenna. They work well, for the money

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trophyboat wrote:
So I found a small white wire coming out of the radio which must be what they figured would work as the antenna. But the connection at the radio appears to not have threads on it. So how would the antenna be connected?

Most AM/FM radios use a "Motorola connector" for attaching the antenna... its just a friction connection. You can buy a new wire antenna WITH plug for $10 from West Marine, there is nothing to 'em. A dedicated "real" FM antenna will provide the best reception. I have a wire as I almost never listen to the radio, and the wire pulls in the stations just fine... so the added cost and antenna sticking out of the boat isn't worth it to me.

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captharv wrote:
A word about splitters. They are a big compromize on performance.

First lets discuss antennas. The AM-FM to VHF radio splitter gets a lot of press, both good and bad. Mostly bad. If the splitter goes bad, goodby both the VHF and sterio. The front end of the radio is not made to take 25 watts, and the VHF transmitter does not like a bad SWR. Hopefully, its protection circuitry will shut down teh transmitter in time. This part is a biggie: The VHF marine radio is a life saving device. I will not attach anything to it which MAY deter performance.

Hey Capt Harv

I don't mean to hijack this thread, but just wanted your opinion on a splitter I have been using for years - it's a Shakesphere automatic switch that allows me to connect 2 VHF radios to one antenna. Have you seen any issues with these?

-Ron

[captharv Founding Member Find all posts View Profile Close captharv]

ronlord wrote:
Hey Capt Harv

I don't mean to hijack this thread, but just wanted your opinion on a splitter I have been using for years - it's a Shakesphere automatic switch that allows me to connect 2 VHF radios to one antenna. Have you seen any issues with these?

-Ron

It is fine, IF it works. Imagine it becoming faulty and disabling boith radios not transmitting, and you are in deep sewage..... Scenario: you become injured and someone else has to call it in. Would they know how to detach the splitter and connect the cable to the main radio directly?

Made my point?

What I have: My main VHF is connected to a shakesphere 5225. My backup radio in the cabin, which is also my PA with a speaker on the foredeck, has a "rubber duck" antenna, which was made to be used with a handheld, hanging from the radios connector. However, I have patch cables which I can used the 5225 on the backup radio, in case of an emergency.

Mostly where I am boating now days, even the rubber duck will reach out 5 miles to another boat, and be heard by the CG with ease.

I also have a Standard 150 handheld as a triple backup.

As said above, I am against putting anything on a lifeline radio which could possibly disable it.

In your case, I remamber you having a 34 mainship. Have the main radio you use connected directly to the big antenna. Buy a 4' antenna with a stainless element and the matching network in a silver can, (Model 5250?) put it on the flybridge and wire it to the other radio. It will get almost as far, is relatively cheap, and most of all, forgetting to lower it under a bridge will not break it. The satinless rod is very springy, not like a fiberglass antenna.

One of my buddies has a go-fast boat (90 MPH) and bought one of the antennas mentioned above. he claims it works better than the "cheap" (Shakesphere 5206) antenna, and he hasn't broke it in 2 years. He does poker runs, and that tortures anything in a boat.

I was a marine radio technician here in Central Florida during the later 70s and early 80s. There were no cellphones. The VHF was the ONLY way to get help. CB aboard a boat was useless. We made sure that the customers who went offshore had the best radio and antennas. We sold a lot of Modar triton 25s (motorola design them for CG boats) and shakesphere 5225s.