Yagi Antenna

Nate The Surveyor

Well-Known Member
My old RTK gps system is a Legacy E, with a PDL 4500 on the rover. And, with a 35 watt Pac Crest Radio on the base.
That thing has better range, than my nice shiny new LS.

I can see what I think is why--- the Legacy E was a component system, with wires. A radio, was free to be a radio. Not all crammed into a little box.

So, as I went looking, it seems that there is some sort of upgrade path. Such as a directional antenna. Yagi.

And, such a thing as an external antenna for the LS. It has a little rubber ducky, with 90° angle to it. It seems to me, that to put a wire on that spot, and to use a WIRE whip antenna, on a stick, might get me better signal. Maybe a signal booster.
Also, I was banging around with another surveyor. They used to have base antennas, that had notches in them. So you could set the precise length, for the exact frequency you were on. Between 450-470 Mhz, there is a total difference of 2 inches! So, it might be good to have a little arsenal of 4 different radio antenna lengths, to swap to, as I use differing frequencies.

Anybody want to discuss range?

Repeaters?

What about 100 watt radios? I'm sure somebody has one of them. In USA, they are not quite legal. But, with proper guidance, you could possibly find a channel, that would allow it. There is always more to any given subject, than meets the eye.

Range. What is the best path, to get lots of range?

Cell telephone. Yeah, not around here. But, maybe with a Wilson signal booster?

Nate
 

Matt Johnson

Well-Known Member
5PLS
It is important to remember that the FCC allows up to 35 watts ERP (Effective Radiated Power) to be transmitted. If you have the radio set to output 35 watts and are using an antenna that isn't a unity gain antenna, such as the 5 dB gain whip antenna then you aren't in conformance with the FCC rules and terms of your license. See http://www.amerisurv.com/PDF/TheAmericanSurveyor_Silver-PirateSurveyors_Jan2014.pdf

There would be no problem with using a higher gain antenna to receive corrections from the base station.
 

Adam

Well-Known Member
5PLS
It is important to remember that the FCC allows up to 35 watts ERP (Effective Radiated Power) to be transmitted. If you have the radio set to output 35 watts and are using an antenna that isn't a unity gain antenna, such as the 5 dB gain whip antenna then you aren't in conformance with the FCC rules and terms of your license. See http://www.amerisurv.com/PDF/TheAmericanSurveyor_Silver-PirateSurveyors_Jan2014.pdf

There would be no problem with using a higher gain antenna to receive corrections from the base station.

I was sold the 5db whip with my radio. I wasnt aware that this antenna would put me over. So what output can I use it safely with?
 

Matt Johnson

Well-Known Member
5PLS
I was sold the 5db whip with my radio. I wasnt aware that this antenna would put me over. So what output can I use it safely with?

10 Watts with the 5 dbd gain antenna. There is an online calculator at http://www.csgnetwork.com/antennaecalc.html

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Adam

Well-Known Member
5PLS
When i went to the link The calculater displays 19.28 Erp and 31 eirp for 10 watt and 5db ant. What's the difference. Which one is the FCC concerned with?
 

Matt Johnson

Well-Known Member
5PLS
When i went to the link The calculater displays 19.28 Erp and 31 eirp for 10 watt and 5db ant. What's the difference. Which one is the FCC concerned with?

If you look at your license you should see that it says 35 watts ERP. For the antenna gain, you need to input 5 dBd rather than dBi. It is a 5 dBd (7.15 dBi) gain antenna.
 

Adam

Well-Known Member
5PLS
Thanks, I am assuming by using the 5db antenna that I am easing the load on the radio. Is that the reason for selling this antenna since I can't legally use it to its full potential. I have a small antenna that screws directly on the radio should I just use that?
 

Matt Johnson

Well-Known Member
5PLS
It reduces battery consumption and heat generation in the radio. In some countries I'm sure it can legally be used at full power.
 

Jim Frame

Well-Known Member
I had read Mark Silver's article before I bought my 35w radio but failed to check the details afterward. I wonder if those 4-mile vectors I got last winter with 35w and the 5dBd antenna would have worked at only 10w?
 

toivo1037

Active Member
I have been using my Triumph 1Ms for a month of so. I have gotten 2.25 miles with the internal 1watt radio over fairly flat terrain, but forested between base and rover. While testing I quit going out any further when I got a bit over 6 miles with my 35 watt radio. A hill, and forest between base and rover, but rover was in a field at the time - base was at our shop, and not in an ideal location. So far I am very happy with the T1M radios. Historically I was down to 2.3 miles on a 35 watt radio with my Hiper. This is night and day difference.
 

Jim Frame

Well-Known Member
It is important to remember that the FCC allows up to 35 watts ERP (Effective Radiated Power) to be transmitted.

When I read this I accepted it without question, so when I used my HP435BT today for the first time in a long while, I set it to 10 watts, as I'm using a 5dBd antenna. I had a little trouble getting reception less than 3 km from the base in an urban area, which had me grumbling about why I bought a 35 watt radio if I can't use 35 watts. But I just checked my license, and it says that I'm limited to 35 watts of output power and 70 watts of ERP. Using the online calculator in Matt's link, that means I can go up to 22 watts without exceeding my licensed limit.
 

Matt Johnson

Well-Known Member
5PLS
When I read this I accepted it without question, so when I used my HP435BT today for the first time in a long while, I set it to 10 watts, as I'm using a 5dBd antenna. I had a little trouble getting reception less than 3 km from the base in an urban area, which had me grumbling about why I bought a 35 watt radio if I can't use 35 watts. But I just checked my license, and it says that I'm limited to 35 watts of output power and 70 watts of ERP. Using the online calculator in Matt's link, that means I can go up to 22 watts without exceeding my licensed limit.

Who did you have process your license? Mine says 35 watts for both ERP and output power.
 
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