Another H/H vhf question or three

[LadyInBed]

What sort of Tx range do you get out of your H/H?
Does it have the ability to connect to your masthead arial?
Have you ever used it in this configuration?
If so what sort of Tx range did you get?

 

[Bergman]

Range depends on height of the receiving aerial - in practice think a max of 2 - 5 miles.

Whether it can be connected to masthead depends on the set. Mine has a "rubber duck" type aerial connected to set by a BNC connector - I could fit a BNC connector on aerial feeder and use that - no technical reason not to but hard to see a reason why you would want to do this.

Most fixed sets use a different PLG239 connector (which is not as good as BNC) which makes it difficult. I suppose someone could make up an adaptor if you were really keen on the idea

Range would be extended - in theory to same as fixed set - range on VHF tends to be limited by curvature of the earth rather than power of transmitter. In practice I would expect a realistic maximum of around 20 miles - mainly because most receivers are not very good with weak signals and also people tend to turn up the squelch control which prevents the receiver from working at all with weak signals.

Hope this helps

 

[bruce]

antenna connectors for most all combinations are available at local ham dealer, radio shack,etc. you could also run a 20 watt ham 2 meter linear amp in line to outside antenna.

 

[VicMallows]

Since we don't have Radio Shack over here, you'll get the converter piece you need at Maplins (many towns or mail order). Tandy used to stock them in most High Streats, but I think they've closed down?

Vic

 

[LadyInBed]

[ QUOTE ]
Range depends on height of the receiving aerial

[/ QUOTE ]
Not quite, it depends on the height of both the Tx and Rx aerial for the same given power o/p
[ QUOTE ]
I could fit a BNC connector on aerial feeder and use that - no technical reason not to but hard to see a reason why you would want to do this.

[/ QUOTE ]
The answer to the second statement is in your first statement!!

[ QUOTE ]
Range would be extended - in theory to same as fixed set

[/ QUOTE ]

This is the sort of thing I am getting at, 3 or 4 Watts out of a H/H. 20 to 25 Watts (depending on cable losses) out of a fixed set. In practice how much is the Tx range of a H/H improved with aerial height, is it approaching the range of a fixed set?
I am not interested in Rx distance, I pick up Portland and Brixham CG at 40 or 60 miles and even picked up a Welsh CG station one night with the help of an ionosphere bounce. Neither am I after the theory of radio wave propagation, I did that a long time ago. I am after actual examples of what range people have achieved on low wattage sets and if people think it worthwhile going for the full belt and bracers approach for interconnectivity.

And on that, have just thought of another question: Does anyone have the ability to connect their emergency aerial to both the fixed and H/H set?

 

[VicMallows]

Yes, by virtue of convertor referred to in my post above ..... though the emergency antenna is home made so could just as well make up two while I'm about it to be doubly sure! ... have plenty of spare coax on board should I loose those!. Hang on, I'd better check up on spare batteries.....

Vic

 

[LadyInBed]

What sort of range were you working Vic?

 

[steverow]

You couldnt possibly have picked up a welsh station by "ionospheric" propogation under normal circumstances.
This is the d layer and it doesnt usually affect frequencies that high.

It would have been the troposphere F1 and F2 layers, or a phenomenon known as "ducting"..which is short lived and usually associated with ridges of high pressure and temperature inversions.

There is no reason why you cant use a BNC/PL259 converter and use the masthead antenna.

Transmitter power is much less of a factor than antenna height.
In theory you have to quadruple your power to double your TX distance but as VHF is essentialy a little more than line of sight medium, the power factor is of little consequence.
It is much more important that both the RX and TX antennae can "see" each other.


Steve.

 

[DRW]

I have carried an adapter for years so that I can plug the handheld into the main radio aerial. It works fine, and is just in case the main set goes down. Always seemed a small and cheap emergency spare.

I've never had to use it in anger and so can't give the range, but at 5 watts would obviously be weaker at distance that a full 25 watts radio. It works well locally.

 

[dickh]

Yes, I made up connectors so I can use either the H/H or the main set with an emergency aeriel. The cable for the emergency aeriel connects directly into the fixed set. aanother cable converts the PL259 on the emergency ariel to the BNC connector on the H/H.
The H/H connected to the masthead aeriel has a range of about 15-20 miles(middle of the Thames Estuary to Walton CG) - no problem with rx & tx.

 

[Bergman]

Quote:
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Range depends on height of the receiving aerial


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"Not quite, it depends on the height of both the Tx and Rx aerial for the same given power o/p"


I had assumed you would use the H/H in your hand at about head height. If you are exceptionally tall or choose to climb the mast then that will be a factor to take into account.

"Neither am I after the theory of radio wave propagation, I did that a long time ago."

Then why do you need to ask?

 

[LadyInBed]

‘cause the theory and the practice hardly ever match. I am curious as to how many ‘boaters’ think the ability to mix and match is worthwhile. On top of that, the ability to do it is one thing, to test out the system and know what sort range is achievable is knowledge in the bank. Similar to knowing the boat or cars range on a full tank of fuel.

 

[LadyInBed]

OK, it was the Fing layer, I knew it wasn’t ground wave /forums/images/graemlins/tongue.gif I wish you could have answered my original post /forums/images/graemlins/confused.gif

 

[BrendanS]

Not exactly an answer to your original question, but I went into the water once to check out range of a good handheld to a fixed VHF, while actually in water, rather than on boat.

see here

 

[LadyInBed]

Interesting that the Rx range was down on the Tx range. I wonder if the squelch was set a bit high, did the H/H have a manual squelch?

 

[BrendanS]

Squelch not a problem, and it is rotary manual. I always set high, even if it gives me background noise. High range hand held, IC-M1EURO V. amateur ham stuff was done too, though years out of date and not used in 25+ years, so not much operator error involved.

I'd expect Rx to be higher on fixed and lower on h/h . Fixed have bigger aerial, and hence better reception. Seen this many times, eg when trying to contact fleet in Hamble while I was in Southampton water. They could hear me, but couldn't contact me

H/h transmission is best when antenna is vertical, and line of sight. Bleedin diffult when in the water