Has anyone used one of these and just how good are they for I wish to tap into the mast head VHF antenna.
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Maybe Not A Good Idea
The local boat electrical author has it in for those, Mark. He always recommends people get rid of them and just stick a cheap auto antenna someplace in the overhead. He says it degrades your VHF and is subject to breakdown. FWIW, Rick D.
The local boat electrical author has it in for those, Mark. He always recommends people get rid of them and just stick a cheap auto antenna someplace in the overhead. He says it degrades your VHF and is subject to breakdown. FWIW, Rick D.
Splitters
Mark, In layman's terms - at VHF all antenna connections must be 'matched'. This means that, to match one antenna into two sets the signal gets divided into half for each set. Also there could be damage to the input stages of the set on 'Receive' when it gets a blast when the other set transmits. Your main VHF radio is a vital safety link with Coastguard and other life saving services so you don't want to reduce both its receiving and transmitting effectiveness by half. The exception to the above is when the two sets are on widely differing frequencies. In this case it is possible to match each set with a tuned circuit. However your VHF antenna is only suitable for the VHF marine band so will be very inefficient when operating outside its designed band. Thus the previous advice from Rick is first rate.
Mark, In layman's terms - at VHF all antenna connections must be 'matched'. This means that, to match one antenna into two sets the signal gets divided into half for each set. Also there could be damage to the input stages of the set on 'Receive' when it gets a blast when the other set transmits. Your main VHF radio is a vital safety link with Coastguard and other life saving services so you don't want to reduce both its receiving and transmitting effectiveness by half. The exception to the above is when the two sets are on widely differing frequencies. In this case it is possible to match each set with a tuned circuit. However your VHF antenna is only suitable for the VHF marine band so will be very inefficient when operating outside its designed band. Thus the previous advice from Rick is first rate.
Not so good
I purchased one of these from Shakespear, as I remember it cost about 40 or 50 dollars. It split the signal between the VHF and provided a needed anntenna for the FM. While it improved FM radio reception (we previously had a car antenna lying in one of lazerettes) it hurt the reception and transmit range for the VHF. I have great reception with a thin wire antenna hidden in salon. I'm not sure where to get one, but it's very similar to the antenna's that were laminated into the windshields in cars. (was that the 70's?) At any rate, it works well.
I purchased one of these from Shakespear, as I remember it cost about 40 or 50 dollars. It split the signal between the VHF and provided a needed anntenna for the FM. While it improved FM radio reception (we previously had a car antenna lying in one of lazerettes) it hurt the reception and transmit range for the VHF. I have great reception with a thin wire antenna hidden in salon. I'm not sure where to get one, but it's very similar to the antenna's that were laminated into the windshields in cars. (was that the 70's?) At any rate, it works well.
Correction - Splitters
I did some calcs. The losses are more likely to be a factor of 4 in voltage terms and thus 16 in power terms. Also it looks unrealistic to get a correct match for both transmission and reception. Perhaps some of you Hams could provide more detail?
I did some calcs. The losses are more likely to be a factor of 4 in voltage terms and thus 16 in power terms. Also it looks unrealistic to get a correct match for both transmission and reception. Perhaps some of you Hams could provide more detail?
Excellent thoughts
Thanks everyone. Perhaps I will try to hide a FM/AM wire up in the headlining??? Any thoughts
Thanks everyone. Perhaps I will try to hide a FM/AM wire up in the headlining??? Any thoughts
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