VHF performance

Although most of the recieve radios use less than an amp, so have amplifiers or an output which is considerably higher. Unfortunately many of the manufacturers use a small wire into the VHF radio itself. This does contribute to the loss. As well as mics, also mic technique can be an issue. You want the mic close to the lips--not a foot away.
 
I have an update on what I have done with the radio.

I added new 12gage wires from the helm bus bars installed by EQ directly to the VHF with an inline fuse. I also re-routed the antenna cable sot hat I don't need the extension.

I went out last weekend and the radio sounded better to my boating friends but that was close range. I asked for a radio check and got a reply. This guy asked for a 5 count so it seems that he was really evaluating my transmission. He said I was clear but weak. When I got home I measured the distance for that radio check and he was 7.6 miles away. This was across water and land but no real population areas between us.

The question I have: is 7.6 miles good, about what you would expect or not so good?

This morning I got out to the boat and measured the voltage drop with the new supply wires and it is just a couple tenths of a volt. I also borrowed a VSWR meter. The meter shows that I am putting out 25+ watts and that the reflections are low - maybe 1.1.

At this point I am thinking that my major problem was probably the small power wires. Also that I am probably get what I can from this radio/antenna combination. If this performance still seems sub par the only other thing I can think that might be a problem is the mic.

Steve
 
Hard to say without knowing how high the land is. If I recall correctly,
Powerboat Reports got up around 16 miles max, over water, with
one of the more expensive antennas. But, that was with 8'
antennas. You have the 4.5' antenna, according to the first post,
so 7.6 miles could be OK. If radio is important to you, I'd go with an
8' whip.

Also, remove the inline fuse, install a fuse block and wire from
there. Read the posts on http://www.thehulltruth.com/ for
professional's opinions on inline fuses. Also, wire with tinned
wire and quality connectors put on with a good crimper.

Mike
 
Steve,

Well at least you have a cleaner installation, good power wiring/connections and less points of failure to your antenna, all good. Distance with a VHF system is quite variable going over land, it is a line-of-sight system. Sometimes reflections off objects, buildings, etc can enhance or cancel signal. All affects signal to noise.

Is your mic detachable? If so, you know what to try next. I'd try talking to the same person first with one then the other, that would be conclusive on the volume issue.
 
VHF transmission is basically line of sight. If your antenna is 8 feet off the water and the reciever's is 8 feet off the water the range is:
8 miles--that is all it will be!

You don't know how high the antenna on the other boat was--but you know how high yours was, and how far away he was.

Since the transmission is clear, I would assume that the mike is OK and go on about your playing with the boat, with assurance you have the best you can with this radio. (25 watts, 1:1 swr==sounds good).

The only other potential issue is the PL 259 connector from the coax to the radio. Some are the pinch the braid/center conductor. Soldered on connectors are better if properly done. There was a recent report on one boat in a group cruising offshore who was getting much better AIS signals. it turned out he had a soldered PL 259 connector and all of the others were the pinch on kind.
 
Steve,
I'd still hold that it has either something to do with the mic or the distance/position from your mouth. It is an FM system, so at that close of range we were at, I can't see how even RF signal attenuation would really be a factor except if the antenna system or RF wiring was nearly inoperable. But at close to 1:1 VSWR, it's almost perfect (now) with relatively little difference in loudness according to your test.

Another curious observation that I forgot to mention was when you switched to your handheld outside of Petaluma, it was nearly the same low volume [to me]. Suggests your voice or mouth position, OR, a big coincidence of same problem with both -- I doubt it.

Maybe the best solution: Speak LOUDER! :lol:
 
Hi Steve,

I think I have improved the weak signal at closer ranges by changing the power wires. It is very hard to know since I did not hear my transmissions in comparison with others. I have listened to my radio from another radio and it sounds okay - but again no comparison.

I have been making sure that I talk directly into the mic and louder than I was. I think the best feedback will be when I get with a group again and can have some comparison with others output.

Thanks,
Steve
 
Yep, agree, the system is usable, go find something else to attack! I still have a list of 20 odd items which I prioritize regularly. Problem is, for every 1 or 2 I get done, another 1 or 2 get added. Part of the fun I guess...can't complain, we have boats, others, well -- they just dream.
 
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