Testing the Diamond Antenna X50 Dual Band Base Antenna compared to the Ed Fong

[CentralFloridaGMRS]

Removed the Ed Fong Antenna (GMRS Version) and placed the Diamond Antenna X50 Dual Band in it's place in the same location. It works just a bit better but I expected more. Next will be  the Tram 1486 UHF Fiberglass Base Antenna over the weekend. I did this  because my 50 watt Radio in my car could hit a base unit over 8 miles away yet the Ed Fong couldn't hit him from my base unit indoors.  The Diamond X50 is doing better getting that contact 8 miles away but it's noisy. Just like the Ed Fong Antenna when I moved the Diamond higher I lost the Orlando 700 repeater so I had to lower it again. Also the SWR  on the Diamond was over 2 on just about every channel. Ed Fong was under 1.5 

[Borage257]

Have you tried tilting the antenna towards the desired repeater? No much, just a little.

[Sshannon]

12 minutes ago, WRPG818 said:

Removed the Ed Fong Antenna (GMRS Version) and placed the Diamond Antenna X50 Dual Band in its place in the same location. It works just a bit better but I expected more. Next will be  the Tram 1486 UHF Fiberglass Base Antenna over the weekend. I did this  because my 50 watt Radio in my car could hit a base unit over 8 miles away yet the Ed Fong couldn't hit him from my base unit indoors.  The Diamond X50 is doing better getting that contact 8 miles away but it's noisy. Just like the Ed Fong Antenna when I moved the Diamond higher I lost the Orlando 700 repeater so I had to lower it again. Also the SWR  on the Diamond was over 2 on just about every channel. Ed Fong was under 1.5 

Unless an antenna is physically broken, simply changing from one omnidirectional to another probably won’t make a radical difference.

I’m really curious about moving the antennas higher and losing the Orlando 700. You say that happened for both the Ed Fong and the Diamond? 

What is the difference in height between the two locations (the Ed Fong or Diamond antenna and the Orlando 700?) Are you higher than the Orlando 700 antenna?  What’s between the two locations?

Did you use the same feed line for both mounting heights? How long and what type?

I wouldn’t expect a big difference between SWR of 1.5 and 2.0. Too much energy is wasted chasing a perfect SWR. Not that it’s wrong to tune an antenna, but you have to look at the entire system. For instance, using feed line with super high losses can result in a really low measured SWR.

Ill be interested in hearing how the Tram works.

 

[Borage257]

Would take off angles have something to do with elevation changes?

Can you “overshoot” another radio/repeater?

[Sshannon]

25 minutes ago, Borage257 said:

Would take off angles have something to do with elevation changes?

Can you “overshoot” another radio/repeater?

Could be. 
Yes, definitely.

A high gain omnidirectional antenna has a flattened propagation pattern when viewed from the side. 

Some repeaters use phased antennas that concentrate their RF toward their intended users, casting it slightly downward usually. If someone were at the same height or higher than one of those arrays they could see a lower signal strength if they raised their antenna higher. It’s like being above the beam. But I don’t know that’s what is happening. 
 

[CentralFloridaGMRS]

1 hour ago, Borage257 said:

Have you tried tilting the antenna towards the desired repeater? No much, just a little.

No. But I do have trees around my house. My guess is the trees are causing it not to work. When lowered it clears the trees I believe. 

[Sshannon]

So for instance, here’s the pattern of the Diamond x50

https://www.diamondantenna.net/x50arad.html
 

Compare it to the X30

https://www.diamondantenna.net/x30arad.html
 

See how the X30 spreads out more, up and down from the centerline?

If you’re far above or below that centerline you’ll see low signal strength. 

[CentralFloridaGMRS]

52 minutes ago, Sshannon said:

Unless an antenna is physically broken, simply changing from one omnidirectional to another probably won’t make a radical difference.

I’m really curious about moving the antennas higher and losing the Orlando 700. You say that happened for both the Ed Fong and the Diamond? 

What is the difference in height between the two locations (the Ed Fong or Diamond antenna and the Orlando 700?) Are you higher than the Orlando 700 antenna?  What’s between the two locations?

Did you use the same feed line for both mounting heights? How long and what type?

I wouldn’t expect a big difference between SWR of 1.5 and 2.0. Too much energy is wasted chasing a perfect SWR. Not that it’s wrong to tune an antenna, but you have to look at the entire system. For instance, using feed line with super high losses can result in a really low measured SWR.

Ill be interested in hearing how the Tram works.

 

On the Orlando 700, it happened to both Antennas, yes. Higher can't get the Orlando 700. I guess trees might be the problem.  Same Feed yes. LM-400. I will update everyone on the Tram this weekend. The Diamond looks great on the roof but doesn't perform as good as I wanted it to. 

[CentralFloridaGMRS]

3 minutes ago, Sshannon said:

So for instance, here’s the pattern of the Diamond x50

https://www.diamondantenna.net/x50arad.html
 

Compare it to the X30 (be right back)

I looked at the X30. Perhaps I can get that one as well. Next is the Tram

[Sshannon]

4 minutes ago, WRPG818 said:

No. But I do have trees around my house. My guess is the trees are causing it not to work. When lowered it clears the trees I believe. 

That would sure do it. Green vegetation is pretty effective at attenuating UHF. 

[Sshannon]

19 minutes ago, WRPG818 said:

I looked at the X30. Perhaps I can get that one as well. Next is the Tram

If trees are the problem I wouldn’t recommend getting the x30. There’s nothing wrong with it; it’s just not going to solve the tree problem. Instead I would try to get above the trees or to the other side of them. 

[CentralFloridaGMRS]

3 minutes ago, Sshannon said:

If trees are the problem I wouldn’t recommend getting the x30. There’s nothing wrong with it; it’s just not going to solve the tree problem. Instead I would try to get above the trees or to the other side of them. 

Trees are too tall to go over them. Reading so many negative comments for the Ed Fong Antenna thought I would try another antenna. Surprised at the results for the Diamond. Will try the Tram over the weekend. 

[Sshannon]

1 minute ago, WRPG818 said:

Trees are too tall to go over them. Reading so many negative comments for the Ed Fong Antenna thought I would try another antenna. Surprised at the results for the Diamond. Will try the Tram over the weekend. 

Take the comments about the Ed Fong antenna with a grain of salt.  Most of them come from commercial radio guys who are accustomed to heavy duty commercial quality. Good enough is good enough and the Ed Fong antennas have a place.

I'm eager to hear how the Tram works.

If your trees lose their leaves during the winter you may find you get better reception until the spring.

[Sshannon]

Also, a Yagi-Uda antenna and a small spot where you can see through the trees might work really well. If you only intend to communicate via the repeater why waste RF in any other directions? 

[CentralFloridaGMRS]

4 minutes ago, Sshannon said:

Also, a Yagi-Uda antenna and a small spot where you can see through the trees might work really well. If you only intend to communicate via the repeater why waste RF in any other directions? 

That's a good question. I have contacts from around Central Florida on Simplex. If I had to pick one repeater I would pick the Orlando 700 The Ed Fong does a great job getting that repeater but I was expecting to get better coverage with a Tram or Diamond. In my Car near my house I get the Orlando 650 and two other repeaters. Perhaps an option would be a Yagi-Uda 

[Sshannon]

9 minutes ago, WRPG818 said:

That's a good question. I have contacts from around Central Florida on Simplex. If I had to pick one repeater I would pick the Orlando 700 The Ed Fong does a great job getting that repeater but I was expecting to get better coverage with a Tram or Diamond. In my Car near my house I get the Orlando 650 and two other repeaters. Perhaps an option would be a Yagi-Uda 

It would be at the expense of some low or null spots along the sides of the antenna.  Everything with antennas is a trade-off. 

[PA141]

I do not have much experience with J-poles but my recollection is that they are a 3/4 wavelength vertical, which is a fairly high angle radiator (peak gain at around 25 degrees above the horizon) and a significant null ( -10dB or more) on the horizon.  It is surprising that the Diamond is not a better performer for a signal on the horizon based on the pattern of the X50 that Steve linked.

Moving the antenna to a different location might also make a significant difference over an obstructed path.

A J-pole would be a great choice for a close by repeater much higher in elevation.  It wouldn't be my first choice for maximum range.

[SpeedSpeak2Me]

The high SWR with the Diamond X50A on GMRS isn't surprising, as it is way out of band for what the manufacturer designed it for.  Antenna is made for 2m/70cm, not 64cm, and it's not tunable.  The Tram 1486 is tunable so that the SWRs for GMRS (simplex and repeater inputs) can be significantly lower.  Once properly tuned the Tram 1486 should have an SWR of 1.5:1 or less across a 10 MHz bandwidth.  From what I understand the cutting/trimming chart that is provided with the antenna is quite accurate.

[Sshannon]

5 hours ago, SpeedSpeak2Me said:

The high SWR with the Diamond X50A on GMRS isn't surprising, as it is way out of band for what the manufacturer designed it for.  Antenna is made for 2m/70cm, not 64cm, and it's not tunable.  The Tram 1486 is tunable so that the SWRs for GMRS (simplex and repeater inputs) can be significantly lower.  Once properly tuned the Tram 1486 should have an SWR of 1.5:1 or less across a 10 MHz bandwidth.  From what I understand the cutting/trimming chart that is provided with the antenna is quite accurate.

That’s true.  Here’s a link to a previous discussion about the X50 on GMRS: 

 

 

[gortex2]

Buy an antenna for the service you want. If your using GMRS buying a HAM antenna isn't going to be the best. As said above the TRAM is a good option for cheap antenna. Although for the price f both of these antennas you could have bought the Laird FG4505 and been done at once. Make sure you trim the TRAM per the instructions. Im not convinced the gains they show are remotely accurate but thats another discussion.

[Sshannon]

I agree with gortex2.  If you’re going to buy another antenna, get one for GMRS, but I would figure out what location works best and then get a GMRS antenna that is appropriate for that location. But although 1.0:1 is better, an SWR or 2.0:1 isn’t what’s killing your signal.  I think you’re right to suspect vegetation.

[aroylance]

What feed line are you using?  in my little experience feed line is a big killer on UHF stuff. I can push over 15 miles on 5 watts with no issues but i am not trying to push through Florida vegitation.  If you can hit it with your car and not the base i would think vegitation is not the issue.  i would look at your coax size and your lightning arrestor. if the arrestor has failed it would not let much go through it. i think the common denominator is the base unit set up.  i would buy an antenna and tune it for the GMRS band for the best results but unless there is a issues withs Ed's antenna  it should get you eight miles pretty reliably.

you have tried 2 differnt antennas without much differance so most likely something else in the set up.

Just my .02

 

[CentralFloridaGMRS]

1 hour ago, aroylance said:

What feed line are you using?  in my little experience feed line is a big killer on UHF stuff. I can push over 15 miles on 5 watts with no issues but i am not trying to push through Florida vegitation.  If you can hit it with your car and not the base i would think vegitation is not the issue.  i would look at your coax size and your lightning arrestor. if the arrestor has failed it would not let much go through it. i think the common denominator is the base unit set up.  i would buy an antenna and tune it for the GMRS band for the best results but unless there is a issues withs Ed's antenna  it should get you eight miles pretty reliably.

you have tried 2 differnt antennas without much differance so most likely something else in the set up.

Just my .02

 

 

LMR-400 Coaxial cable

[aroylance]

that should work. just seems like there is an issue with the base setup 

[WRYV757]

You could try co phasing antennas vertically, one at the the height you know works for the one repeater and the the other at the other available height.

The antennas would need to be the same and the harness feeding the antennas would need to be 75ohm. The distance of each feeder cable would need to be equal and in odd 1/4 wave lengths. just a thought and it would give added gain vs the single antenna if done correctly