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eHam Forums => Elmers => Topic started by: KB3HYM on March 02, 2013, 11:24:29 AM



Title: 2 meter SSB range
Post by: KB3HYM on March 02, 2013, 11:24:29 AM
What is the expected range in miles, that I could see with a vertical mobile antenna SSB on @ meters?  I understand that my limitations with being vertically polarized as opposed to being horizontally polarized.


Title: RE: 2 meter SSB range
Post by: KA4POL on March 02, 2013, 11:36:52 AM
On a hill with say 10 Watts under normal conditions about 100 miles +/-50. It is really difficult to say and therefore just a rough guess.


Title: RE: 2 meter SSB range
Post by: KB3HYM on March 02, 2013, 11:41:46 AM
Going to get on top of hill early this evening and play radio.  Hope I can make a contact.


Title: RE: 2 meter SSB range
Post by: W8JX on March 02, 2013, 11:53:24 AM
Going to get on top of hill early this evening and play radio.  Hope I can make a contact.

Good luck but you might start on FM and see if it can lead to SSB.


Title: RE: 2 meter SSB range
Post by: G3RZP on March 02, 2013, 11:54:11 AM
It all depends on conditions. I've worked over 800km on 2m CW with 10 watts out and a 17 ele horizontal beam at 40 feet. I can usually hear 25 watt beacons at 250km.

CW can be your friend: I did notice the one time I was operating ina VHF/UHF contest in the US how easy it was if things were too rough to get the QSO finished on CW, while over here, most VHF ops have no hope if you need to use CW. There's a tendency to think of a key as something with which to open the front door.


Title: RE: 2 meter SSB range
Post by: AA4PB on March 02, 2013, 12:06:10 PM
On a hill with say 10 Watts under normal conditions about 100 miles +/-50. It is really difficult to say and therefore just a rough guess.

How high is the hill? How high up is the other station and how much gain does his antenna have? Are there any blockages in between? Is it every day line of sight propagation or is there some ducting going on that day? SSB isn't going to be all that much different than FM. If you can get 10 miles on FM then you might get 12-15 miles using SSB, everything else being equal.

Don't forget that if the other station is using horizontal polarization (the normal for SSB) and you use vertical then you have around a 20dB additional loss if there aren't reflections or some other propagation going on that rotates the signal polarity.


Title: RE: 2 meter SSB range
Post by: WB6BYU on March 02, 2013, 12:39:23 PM
It depends on your antenna, your power level, and the antenna polarization
at the other station.  With a mobile antenna like the fourth one down here (http://commfaculty.fullerton.edu/woverbeck/mtntops.htm)
you might be able to work another station over a 480,000 mile path.

But for general work on a normal mobile whip you might get 10 or 20 miles
unless the person at the other end can switch to vertical polarization.


Title: RE: 2 meter SSB range
Post by: W4KYR on March 02, 2013, 12:53:52 PM
 Like others have said, both stations really should have the same polarization. Let us know how the hill topping went and how high the 'hill' was....

A friend back in New Jersey was able to have regular contact with a station in Rhode Island using 160 watts into a 10 element beam antenna on 2 meter SSB. His propagation was practically an all water path.

(All water paths can be a good substitute for those who don't have high hills or mountains to go to. There have been countless reports of great DX over water paths. FL to TX are possible under great conditions.)

I recommend getting at least a 3 element antenna for hill top excursions or for any kind of SSB communications. You can get a small tripod and a couple of 5 foot masts and the 3 element beam that should easily fit in the trunk and then put it together real quick to do some hill top DX.


Title: RE: 2 meter SSB range
Post by: G3RZP on March 02, 2013, 01:53:12 PM
Yup, if you want to go /P, follow KYR's reccommendations


Title: RE: 2 meter SSB range
Post by: KB1GMX on March 02, 2013, 03:21:13 PM
For SSB you get better results matching the others you can talk to, horizontal.

As to how much antenna, a simple dipole at 10ft on a painters pole show get you
a lot of miles from a hill.  If the hill is large and your average height is also larger
than surrounding that could be over 100 miles.

I'd strongly suggest a simple three or four element  and  simple mast to get some height
like 10 feet or more  Then you will be assured of better results.

Using a 6 element beam at 20ft and 10W I used to work more than 100 miles from home
(not on a hill) during contests and occasionally to 200 plus miles.

10W is plenty of power, use a horizontal antenna and your good to go.

Allison


Title: RE: 2 meter SSB range
Post by: KB3HYM on March 02, 2013, 04:48:41 PM
Thanks for all the suggestions!


Title: RE: 2 meter SSB range
Post by: AA4HA on March 02, 2013, 06:12:54 PM
An idea on how much the polarization will affect you;

Using vertical while the other station is horizontal will bring your signal 20 dB down.

You could always make yourself a 3 or 6 dB Yagi antenna and mount it on a mast, even a portable installation. When you are on FM you keep the antenna on vertical polarization (elements pointing straight up and down). When on SSB you can rotate the boom for horizontal polarization (elements parallel to the ground).

As you increase in frequency (+VHF) signals become much more dependent upon LOS (line of sight) and atmospheric "boosts" are less likely (look up MUF (Maximum Usable Frequency) and propagation effects). There are some atmospheric "tricks" like ducting, superrefraction, etc... that can help you out but you cannot depend upon them for 24/7 performance. I suggest trying to work LOS paths with someone by prior arrangement first so you get a feel for how long distance >VHF communications over distance works.

Height is indeed your friend. Minimizing obstructions due to buildings, terrain and trees will help you out.


Title: RE: 2 meter SSB range
Post by: G8YMW on March 03, 2013, 06:21:58 PM
I'll give you my experiences on 2 metres.
50 watts to a mobile whip, circa 100 k
5 watts to a horizontal omni ( A cloverleaf, Wimo Big Wheel) 360 k Lincoln ( Not renowned for big hills) to GI land under flat band conditions (Have worked into France but not sure of conditions)
The Cloverleaf is the biggest PRACTICAL mobile aerial (A halo is a lot better than a vertical but not a patch on a Cloverleaf) but as suggested by others a small yagi is better for /P  plus it doesn't take many seconds to swap polarity.


Title: RE: 2 meter SSB range
Post by: K0ZN on March 06, 2013, 08:02:15 PM

WAY to many variables.... terrain being one of the biggest.  Out in Colorado and Wyoming I have had 110 mile simplex contacts on FM.
I have had 2 M SSB mobile-to-mobile contacts using whips of 35 miles at times in the midwest. I have heard guys with stacked halos in a
mobile at over 100 miles regularly.  If you are stopped on a high hill the range can be amazing....SSB will go a LOT farther than FM.
...if you are in a low spot you might struggle for 3 to 5 miles depending on where the other station is. (This assumes you are NOT working a repeater on an 800 ft. tower !)

73,  K0ZN


Title: RE: 2 meter SSB range
Post by: G7MRV on March 06, 2013, 09:41:37 PM
Dont limit yourself to your vehicle whip when out mobile. Although I cant use it when actually moving, I carry a small, 3 element beam with me for SSB use. Its a design by Martin DK7ZB (take a look at his website) made from the remains of an old VHF broadcast beam, and uses wing nuts to hold it together, so I can either dismantle it entirely or just fold it up (not as small). That with a 5m coax patch lead and a telescopic fibreglass mast (fishing pole) makes a near as dammit instant SSB station - pull up, rig up and Im away.

If your going to a hill top, your going to be parked up anyway. A few minutes to rig up a simple beam will massively increase your success. If you have a suitable fixing on the top of your car (roofbars etc), a very simple jig will hold a fibreglass mast vertical for you so you dont have to.

Martins antenna designs are very forgiving of thickness etc of materials. Mine is made from wide ali tube with broad ali mounts, but with Martins help we came up with a fudge factor for the dimensions (about 5% shorter i think it was on mine) and it works perfectly

My problem at the moment is i no longer have roof bars so have to put guys out for the mast!


Title: RE: 2 meter SSB range
Post by: K0CBA on March 14, 2013, 06:45:46 PM
Polarization won't make much of a difference because no one is there.  2 SSB/CW has become pretty much of a waste land in most areas.