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Discussion Starter #1
I understand the basics on how these work, but I''m wondering what the downside might be.

Is there any reduction in VHF performance? Any other issues? Anybody use this before and comment on its performance. Particularly whether the AM or FM performance is enhanced (or both?)

(GordMay.....any comments)
 

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I have used the Double Throw + Ground antenna switch, connecting two radios to a single antenna (and grounding antenna when both radios off).
As I recall, there was a very small dB loss, and the switch was very well constructed. The boatowner, with whom I still communicate (3 years later), reported his satisfaction.
Unfortunately, I don''t recall the manufacturer.
I''ll look for my literature, but it''ll be a week or so.
 

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Discussion Starter #3
I was thinking about the Shakespeare Manuf. Part #: 4357-S

West Marine has it. http://www.westmarine.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10001&langId=-1&catalogId=10001&productId=20219

Is that the same one you were looking at or is this one different? I didn''t know about any grounding.
 

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Discussion Starter #4
ps. I don''t think the one I''m looking at is a switch. I think its a "combiner" of sorts and would allow simultaneous use of VHF and AM/FM at the same time.

I have no delusions that when I transmit VHF that my AM/FM radio would work very well though.....but thats ok.
 

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Hi Tsenator,

I connected two of these Shakespeare dividers in each of VHF antennas, one at the mizzen and other in the main mast.

BOth antennas are connected to different VHF equipments, and one is connected to FM and AM radios, and other VHF divider to the TV tuner.

All the equipment continue to work .

I did measure the ROE of VHF and did not loose any db. (Measured with analog meter)

Regards
 

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Discussion Starter #6
[email protected],

Thank you very much for your input.

Did you notice any great improvement in the AM or FM reception? I heard one person say they were dissappointed in the FM reception with the device and it barely helped any. How about the AM reception, any better?

Is this device worth it?
 

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I can''t see there such a device would be worth it.. Too much induced loss in VHF. And the VHF is too important to fool with. There are other ways to get better reception. Look at the JC Witney catalog even online and see what they have...
 

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Discussion Starter #8
jbanta,

I agree in theory. And normally I would agree, but both "fer" and Gordmay (well respected authority on Marine electronics and communications) said it looked like there was little or no signal loss.

And even if it did "screw up my signal/reception/transmission" on my VHF it would be very easy to remove where I have it located. I have easy access to the back of my VHF. Plus I have backups.

But if a $60 part doesn''t hurt my VHF and really helps the radio reception then I''ll be happy, as reception can be poor for the stations I''d like to listen to.

But looking in JC whitney is not what I''d like, and I don''t think the reception could match the potential of the mast head VHF antenna in height....and that really is what I''m looking to take advantage of.
 

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Discussion Starter #9
jbanta,

I agree in theory. And normally I would agree, but both "fer" and Gordmay (well respected authority on Marine electronics and communications) said it looked like there was little or no signal loss.

And even if it did "screw up my signal/reception/transmission" on my VHF it would be very easy to remove where I have it located. I have easy access to the back of my VHF. Plus I have backups.

But if a $60 part doesn''t hurt my VHF and really helps the radio reception then I''ll be happy, as reception can be poor for the stations I''d like to listen to.

But looking in JC whitney is not what I''d like, and I don''t think the reception could match the potential of the mast head VHF antenna in height....and that really is what I''m looking to take advantage of.
 

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I bow to the well respected authority on Marine electronics and communications. Just rememeber that any additional connector in the cable adds not just loss but also to the SWR. I was Radio in the service and it never took alot to start getting almost as much reflected power as my PA was putting out.
 

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I bow to the well respected authority on Marine electronics and communications. Just rememeber that any additional connector in the cable adds not just loss but also to the SWR. I was Radio in the service and it never took alot to start getting almost as much reflected power as my PA was putting out.
 

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Gord May should NOT be confused with Gordon West, the well known authority on Ham Radio & Electronics. Mr. West generally sells his opinions, & I have''nt noticed his presence on this forum.
While I do consider myself somewhat "expert" in marine systems (particularily electrical), and have many strongly held opinions, my endorsement of antenna splitters is "lukewarm".
I have not noticed any appreciable degradation of VHF performance, when properly installed.
A splitter cannot be expected to improve radio reception, except as compared against an installation otherwise without an external antenna.
I have seen them used to ensure that a VHF radio antenna is "disconnected" when the SSB radio is transmitting - but I prefer to use a "double throw" power supply switch (to the radios) in this instance. I''ve also seen them used to provide a "quick connect" to a rail-mounted emergency antenna (in the event of dismasting, and loss of mast-top antenna). I prefer to merely run a co-ax from the radio area to the rail location (seal the outside PL connector against moisture) and store the emergency antenna until connection required (hopefully never).
The "grounding" feature is usefull in lightning amelioration.
I hav''nt used the Shakespear switch, and still cannot recall the manufacturer of the one I''ve been satisfied with (it was green).
Regards,
Gord May (not "Gordo" West)
 
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