Duplexer

[JamesBrox]

My OCD kicked in on this GMRS repeater project. Is MY labeling correct on this duplexer?

Thx WRXU693

[JamesBrox]

1 hour ago, nokones said:

"East Coast"

The Florida panhandle. 

[Sshannon]

1 hour ago, JamesBrox said:

Anyway I was asking about your meter. It's reading SWR or watts? I can see watts but what does that mean in performance of the repeater?

That’s a Bird 42 directional wattmeter.  It’s generally considered to be one of the most precise instruments for measuring RF power flow. It measures the power flowing in one direction only. Then you reverse the element to measure the power flow in the other direction. SWR can be calculated from those two measurements, but the important thing is to maximize your flow towards the antenna and minimize the flow reflected from the antenna. 

[JamesBrox]

1 hour ago, Sshannon said:

That’s a Bird 42 directional wattmeter.  It’s generally considered to be one of the most precise instruments for measuring RF power flow. It measures the power flowing in one direction only. Then you reverse the element to measure the power flow in the other direction. SWR can be calculated from those two measurements, but the important thing is to maximize your flow towards the antenna and minimize the flow reflected from the antenna. 

I knew you would come through. Yeah, I just read the same exact wording on google search. A digital SWR meter does the same thing without the calculations, right? So, I need this meter to be successful in knowing what going on, on a gmrs repeater set-up? Forgive me, but it looks like HAM equipment.

[Sshannon]

4 hours ago, JamesBrox said:

I knew you would come through. Yeah, I just read the same exact wording on google search. A digital SWR meter does the same thing without the calculations, right? So, I need this meter to be successful in knowing what going on, on a gmrs repeater set-up? Forgive me, but it looks like HAM equipment.

The same exact wording, huh?  I doubt it, because no part of what I wrote came from a google search.

Forgive you, because it looks like HAM equipment?

The Bird is one of those tools that many commercial radio technicians are likely to own.  I’m sure there are quite a few hams that buy them as well, but probably not on the new market.  I don’t have one, but I wouldn’t turn one down, if someone gave me one with all the necessary elements.  You can be successful with or without one, but there’s no point to having one if you don’t know how to use it.

A digital SWR meter, like that SW102 you have, looks at both forward and reflected power simultaneously and does the calculations for you. Its usefulness is limited by the accuracy of its measurements. There’s a reason Bird meters cost what they do.

 

[BoxCar]

JamesBrox - 

If you are considering putting up a repeater the first thing to consider is what do you want to do with the repeater. Is it primarily for local ( 5-10 mile) service or do you want a longer range? Range will be the primary cost consideration. More range, more expensive - period. Local service can be handled with one of the little 5 watt units on a 35 foot high antenna. Longer ranges mean high cost towers going up 50 or more feet and higher output transmitters. A 50W GMRS transmitter unit will cost new around $1500 - $2000. The tower another $5 to 25,000 depending on height and construction. As you are in Florida, think highest cost due to hurricanes. Then there is the antenna and feed line costs. You'll want an antenna with gain, 3 to 9 dBd or better. The transmission line should be hard line, not normal coaxial cable like RG8 or LMR. Hardline cable starts around $4 a foot so 50 feet is over $200 plus connectors. The antenna ranges from around $100 to over $2500.

A 35 foot mast can be aluminum or fiberglass, you can even make one from PVC pipe. It will need guy wires to keep it straight and vertical in normal winds but will have to be taken down during a hurricane. You are still looking at spending a couple hundred dollars for even PVC. The Ed Fong J-Pole antennas work, but have no gain which means any power losses from your feed line and antenna mismatch won't be compensated for.

[Sshannon]

This was one of the first threads I delved into when I first got my GMRS license and joined this forum.  It should almost be required reading:

 

[JamesBrox]

6 hours ago, Sshannon said:

This was one of the first threads I delved into when I first got my GMRS license and joined this forum.  It should almost be required reading:

 

Yes, I read that article and yes...it should be required reading.  

First thing to consider, are there any open well placed repeaters in your area that you are able to use? I can assure you most repeater owners want people to use there repeater. Owning several repeaters I can assure you all are welcome and encouraged to use my machines.

Yes, It's pretty open at my property.

No, on any open repeaters in my immediate area where a lowly gmrs HT user can hit anything.