Antenna signal question

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I have a Diamond X50 mounted on the gable end of my 2 story colonial. Its about 35 feet up (give or take).

According to my GPS, I'm at about 300 ft above sea level.

Unfortunately, I live in the shadow of a couple hills that are to my west-southwest and are at about 400-450 ft based on the USGS maps.

Because of this, I hit some dead spots in Leominster (which are in the opposite shadow of the hills).

I guess my question is this. Does my 2m antenna have a "take off angle" for its signal? Does it just send out the signal parallel to the ground or does it angle up a few degrees? I obviously don't want to install a 100 ft tower (my neighbors would just love me for that [grin]). Just trying to figure a way around this, if there is one.

Would 10m or above have similar issues? Would people in the opposite shadow hear me?

My location is basically in the area of the red X. Yeah...you know where I live now [grin].

SyICCXG.jpg


Notice that there are two hills that top out at around 450 ft.

Here is the radiation pattern for the antenna. I'm not sure how to read this, so tutelage is welcome.

http://www.diamondantenna.net/x50arad.html
x50a-147.gif
 
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I have a Diamond X50 mounted on the gable end of my 2 story colonial. Its about 35 feet up (give or take).

According to my GPS, I'm at about 300 ft above sea level.

Unfortunately, I live in the shadow of a couple hills that are to my west-southwest and are at about 400-450 ft based on the USGS maps.

Because of this, I hit some dead spots in Leominster (which are in the opposite shadow of the hills).

I guess my question is this. Does my 2m antenna have a "take off angle" for its signal? Does it just send out the signal parallel to the ground or does it angle up a few degrees? I obviously don't want to install a 100 ft tower (my neighbors would just love me for that [grin]). Just trying to figure a way around this, if there is one.

Would 10m or above have similar issues? Would people in the opposite shadow hear me?

My location is basically in the area of the red X. Yeah...you know where I live now [grin].

Notice that there are two hills that top out at around 450 ft.

You should be able to find a graph online somewhere of that antenna. If not that one then something very close. It will show you the dispersion of the signal The angle is determined by ground conditions, height of the antenna etc. You can probably tweak things to improve your signal.
 
I was just about to post the radiation plot you added. Essentially, the plot is telling you in which directions the signal strength will be, allowing you to aim your antenna to tune reception and transmission. If one of the "lobes" isn't facing the hills, you might have a better result by turning your antenna. good luck, IANAH
 
Hmmm...ok.

I was assuming that chart is a side view of the vertical plane. And it is showing me a toroid (side view).

Not sure I can aim this guy since It would be omnidirectional...at least...I assume it is.
 
Hmmm...ok.

I was assuming that chart is a side view of the vertical plane. And it is showing me a toroid (side view).

Not sure I can aim this guy since It would be omnidirectional...at least...I assume it is.

I believe you're correct. The 90 degree plane would be the horizon, and the 0 degree plane would be straight up. You may have some areas of weak signal path due to the terrain, but overall that's a nice antenna and assuming it's tuned OK and you don't have too much loss due to crappy coax, you should do fine on 2m / 70cm. No comment re: 10 meters for close range use, but I believe we're in a declining sun spot cycle with 10 meters being less and less reliable over longer distances. I do know that when 10 meters opens up it can be really great, but I think those opportunities aren't all that often.
 
Living where you are you're probably going to have huge nulls to the west and the south, most of north central MA sucks in those directions. Can you get into Mt. Greylock? 146.91? (if it's still up) if that comes in strong you are lucky. On ground wave most bands are going to have the same limitations (line of sight, although lower frequencies better usually with this).

-Mike
 
10 meter should bend over those hills. How crowded are the 10 meter frequencies these days?

They're dead, all the time, unless the propagation is really good. Honestly though illegal CB/11M is better for skip in that part of the spectrum because the operators are at least around. Most hams have given up on 10M unless they're contesting or something.

How to tell if 10M is (potentially) open... tune in to 27.025 AM and see if the superbowl is up. Yeah it is CB stuff but if those guys are hitting you 30 over 9 then the band is probably open, considering 95% of the signals won't be coming from new england. That said there is a shitload of Sporadic E that happens on 10-12M during the summer and the windows can open and close pretty quickly.

The funny thing is if you only get S7-S9 signals on the superbowl don't even bother with 10M. You'll never hear most hams, as most hams don't run illegal power on 10M. (some do on 20/40/80, but very very few on 10).

-Mike
 
Living where you are you're probably going to have huge nulls to the west and the south, most of north central MA sucks in those directions. Can you get into Mt. Greylock? 146.91? (if it's still up) if that comes in strong you are lucky. On ground wave most bands are going to have the same limitations (line of sight, although lower frequencies better usually with this).

-Mike

Tone is 162.2

Greylock is definitely still up. Traffic net just ended.
 
Tone is 162.2

Greylock is definitely still up. Traffic net just ended.

Thanks, I didn't know, because I haven't tuned into it in forever, I can't get into it unless I put up a Yagi and aimed it that way to blunderbuss the piss out of the mountain or whatever it is in that direction. (I'm in FN42CN).

-Mike
 
I believe you're correct. The 90 degree plane would be the horizon, and the 0 degree plane would be straight up. You may have some areas of weak signal path due to the terrain, but overall that's a nice antenna and assuming it's tuned OK and you don't have too much loss due to crappy coax, you should do fine on 2m / 70cm. No comment re: 10 meters for close range use, but I believe we're in a declining sun spot cycle with 10 meters being less and less reliable over longer distances. I do know that when 10 meters opens up it can be really great, but I think those opportunities aren't all that often.

Roger. I'm sure it's a vertical antenna. Assuming he wants to work repeaters on FM that is the way to go. If he's thinking 2m ssb then I believe most of those folks work a horizontal antenna. I've never tried. Can someone help him with the ideal height? Someone with the EZnec software should be able to figure that out.
 
Thanks, I didn't know, because I haven't tuned into it in forever, I can't get into it unless I put up a Yagi and aimed it that way to blunderbuss the piss out of the mountain or whatever it is in that direction. (I'm in FN42CN).

-Mike

That's a good distance especially with all the mountains and whatnot. We'd be next door neighbors in Iowa [smile].

As an aside, I love talking about radio but I never use it. I really need to fix that.
 
Living where you are you're probably going to have huge nulls to the west and the south, most of north central MA sucks in those directions. Can you get into Mt. Greylock? 146.91? (if it's still up) if that comes in strong you are lucky. On ground wave most bands are going to have the same limitations (line of sight, although lower frequencies better usually with this).

-Mike

Will try Mt. Greylock tonight when I get home. Paxton is not an issue for me given it is 1370+ feet up above sea level.

I tried Greylock earlier, but was using the dead 145 freq. I may have bounced into it once, but the signal was just above the noise level and I really couldn't make much out.

According to QRZ, Mt. Greylock is at bearing 266 at 82 miles. So, depending on the altitude of the repeater antenna, I may be on the very edge of it. I just got my amp/pre-amp setup, so, I'll see how that goes.

Paxton is at bearing 222 at 22 miles...so...not a great comparison...but if what the Mt. Greylock page says is accurate, they have a range of 250/300 miles, I should hear it.

NoBARC's repeaters at 4000 ft typical range without obstruction 250/300 mi circle. This is the widest coverage repeater on the East Coast.
 
Thanks, I didn't know, because I haven't tuned into it in forever, I can't get into it unless I put up a Yagi and aimed it that way to blunderbuss the piss out of the mountain or whatever it is in that direction. (I'm in FN42CN).

-Mike

Mike, would love to try simplex with you based on your location. You are about in the dead zone of which I speak.
 
Mike, would love to try simplex with you based on your location. You are about in the dead zone of which I speak.

I might PM you and set up a sked, gotta figure out if I'm gonna be home tonight or not. Out of curiousity, can you hit Fitchburg 147.315 + (I think PL is 100 or 88.5). That should be an easy hit from your place. There's also the 145.450 machine but that thing is trash compared to 315. ( not to mention, may not even be there anymore because the hospital is being demolished, but I'm not sure). I can hit Paxton, Westford, Waltham, most of the southern NH repeaters of any consequence, etc. Western MA or even out past Westminster is tough for me.

-Mike
 
Will try Mt. Greylock tonight when I get home. Paxton is not an issue for me given it is 1370+ feet up above sea level.

I tried Greylock earlier, but was using the dead 145 freq. I may have bounced into it once, but the signal was just above the noise level and I really couldn't make much out.

According to QRZ, Mt. Greylock is at bearing 266 at 82 miles. So, depending on the altitude of the repeater antenna, I may be on the very edge of it. I just got my amp/pre-amp setup, so, I'll see how that goes.

Paxton is at bearing 222 at 22 miles...so...not a great comparison...but if what the Mt. Greylock page says is accurate, they have a range of 250/300 miles, I should hear it.

Mt. Greylock itself is 3,491' tall. The antenna is the highest structure on the mountain (taller than the monument) but I don't know what the height is.

I'm working from home right now so I'll leave my HT on and listen. The repeater has been quiet for a while now.
 
I might PM you and set up a sked, gotta figure out if I'm gonna be home tonight or not. Out of curiousity, can you hit Fitchburg 147.315 + (I think PL is 100 or 88.5). That should be an easy hit from your place. There's also the 145.450 machine but that thing is trash compared to 315. ( not to mention, may not even be there anymore because the hospital is being demolished, but I'm not sure). I can hit Paxton, Westford, Waltham, most of the southern NH repeaters of any consequence, etc. Western MA or even out past Westminster is tough for me.

-Mike

I can hit Fitchburg, but have to bump up to 65W to be heard best. 25W is a bit low, but readable. I can hit Gardner as well and be heard.

I think it is just a function of the people I'm trying to hit in Leominster...pretty sure they are on HT. A friend over in Ayer can hit them clear as day though. So, that is what leads me to believe it is the hills causing me grief.

I'll check PM tonight when I get home. I'm usually home by 530pm.
 
I was listening. You were obviously getting through strong enough for the repeater to latch on, but it was mostly noise. A few times I was able to make out "radio check" or something like that but nothing else. I turned it off when it sounded like another net was kicking off, around 7:00.

If you're going to try again I can listen in again.
 
At present time, there is a fair VHF/UHF band opening 9:20pm 1/5/16. I can usually reach Mt Grey from Quincy when condx are good.


Sent from my iPhone using Tapatalk
 
I was listening. You were obviously getting through strong enough for the repeater to latch on, but it was mostly noise. A few times I was able to make out "radio check" or something like that but nothing else. I turned it off when it sounded like another net was kicking off, around 7:00.

If you're going to try again I can listen in again.

Heh...yeah...that was me. I heard a net kick off on that frequently at 7pm and I swear it was a ARES net from New Jersey. Ocean State Energency Communications. I checked the NJ repeaters list and that seems to match up with Toms River!! This is the first opening I've taken advantage of.

I just QSO'd with a guy in Leicester. He runs a simplex net Tuesday nights at 10pm on 146.565. He's about 25 miles away at bearing 223. W00t!
 
I have a Diamond X50 mounted on the gable end of my 2 story colonial. Its about 35 feet up (give or take).

According to my GPS, I'm at about 300 ft above sea level.

GPS altitude is pretty useless for an application like this. The vertical precision may be a major fraction of the heights of your local hills above their bases.

Unfortunately, I live in the shadow of a couple hills that are to my west-southwest and are at about 400-450 ft based on the USGS maps.

Because of this, I hit some dead spots in Leominster (which are in the opposite shadow of the hills).

I guess my question is this. Does my 2m antenna have a "take off angle" for its signal? Does it just send out the signal parallel to the ground or does it angle up a few degrees?

Yes; your graph shows the maximum power output is about 5° above horizontal, but the primary lobe is pretty wide.

I obviously don't want to install a 100 ft tower (my neighbors would just love me for that [grin]).

Ironically, if you could prove that you needed a 100' tower to get the line-of-site to perform the type of communication you want to do, then there's case law that you would be entitled to it regardless of what the neighbors wanted.

However, the town might require that (among other things), the tower must be sited such that if it fell over, it wouldn't touch the property line. So you might not have room for such a tower anyhow.

Just trying to figure a way around this, if there is one.

Best bet is to convince yourself that there's no one worth talking to in Leominster, hi hi.

... My location is basically in the area of the red X. ...

Notice that there are two hills that top out at around 450 ft.

I PMed you a HeyWhatsThat horizon plot for your home QTH, but I got the antenna height wrong, and the site may have the wrong altitude for your house.

Be sure to play around with "[ ] show 0° and 1° alt" and "Visibility Cloak".

Here is the radiation pattern for the antenna. I'm not sure how to read this, so tutelage is welcome.

Study the material relating to problem question E9C08 in the 2012-2016 Extra Class question pool.
 
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