Retevis RT97s issue

[4x13]

I have the repeater installed, and the radios using the repeaters but my issue is performance. Being that the repeater is a 10 watt unit and my hand held radios are 2 watts, I would expect at least 3+ miles of distance, but I am only getting about 1 mile.

Any ideas what this issue may be? The antenna is mounted at 10' but it is on top of a plateau about 150' above the heavily wooded valley.

 

Is the repeater not configured correctly?

 

Suggestions appreciated

[gortex2]

Sounds about common to me. What kind antenna system are you using on the RT97 ? Also what radios are you using ? Are they programmed to use the repeater ? 

 

[Sshannon]

7 minutes ago, 4x13 said:

I am living in a densely tree area.

This is probably the issue. UHF just doesn’t pass through moisture bearing vegetation. 

[Sshannon]

4 hours ago, 4x13 said:

Hmm, is there a solution to this issue? Bigger antenna?

Bigger (taller so they are above the trees) antennas for all of the radios would help but there practical limitations. Same for power output.

Different frequencies are less affected. You might listen in to see how 2 meter ham radios do in your area. 

 

 

[WRWE456]

Deleted.

[WRWE456]

That may just be your issue. RG-11 is 75 ohm TV/video cable. You want 50 ohm for radio.

[OffRoaderX]

Does not sound common at all to me, based on actually having and using several of these repeaters.  

• Is the duplexer tuned for the frequencies you are using?
• Is your antenna tuned for those frequencies and have you checked the SWR of the antenna with the cable attached?
• Are all the radios IN the heavily wooded valley or are you trying to test with no line of sight?

[4x13]

The Antenna was sold with the RT97s direct from Retevis, so I would assume it was tuned correctly.

The radios being used are the Rugged Radios 2Watt GMR2 with standard antennas.

I also have a couple BTech GMRS radios with High-Gain whip antenna but I am seeing the same results with both hand held units.

I am living in a densely tree area.

I have verified that that all radios are using the repeater. I have the repeater set to RPTR15 136.5 and unless the radios are configured as such, the base station doesn't connect

I am wondering if there are some settings in the repeater that can be adjusted to increase the output.

I would think that the distance would be much greater than 1-1.5 miles. If this distance is to be expected, what can be done to increase the distance?

I am waiting for the 25' flag pole antenna (flagpoleantennas.com) to become available, but if anyone knows of a non-metallic flag pole antenna that is presently available please let me know.

I have not yet tested the SWR, meter is on order. I do apologize I am new to all of this, so any suggestions are appreciated.

[OffRoaderX]

1 hour ago, Sshannon said:

This is probably the issue. UHF just doesn’t pass through moisture bearing vegetation. 

Moisture bearing vegetation is even worse than houses full of .. .fat people!

[4x13]

Hmm, is there a solution to this issue? Bigger antenna?

[gortex2]

I dont see where you specified cable for the antenna eiither. For the RT shortest antenna cable the better. Better antenna and height. How heigh is the antenna now ? It needs to be up in the air. 

[Sshannon]

2 hours ago, gortex2 said:

How heigh is the antenna now ? It needs to be up in the air. 

He said:

Quote

The antenna is mounted at 10' but it is on top of a plateau about 150' above the heavily wooded valley.

 

[back4more70]

On 2/27/2024 at 10:34 PM, OffRoaderX said:

Moisture bearing vegetation is even worse than houses full of .. .fat people!

Hey, just because I sit around the house doesn't mean I sit AROUND THE HOUSE

[back4more70]

On 2/24/2024 at 1:25 AM, 4x13 said:

Being that the repeater is a 10 watt unit

Not that it matters much, but the RT97S is 5 watts after the duplexer, if I read the specs correctly.

[gortex2]

Thanks @Sshannon I missed that in the firt post. So I guess my original statement stands. An antenna 10' off the gorund with a 5 watt UHF repeater into 50' of LMRish cable and an antenna isn't going to cover too far. I think many have this misconception that they can buy stuff throw it up and talk 50 miles casue other talk about that on the forum. Throwing an Midland/RT97 on a silo thats 150' in the air and field all around will cover better than the earlier one. I posted once previously about my Motorhome experiences.  With 15' of cable and a good Laird antenna I got difference coverage depending on where I parked. 

 

[4x13]

I get there are limitations, and I am by no means an expert. I was trying to get a distance of approx 3-4 miles.

The cable length is about 75'

 

 

[gortex2]

I'd shortne the cable to bare minimum. 

[Sshannon]

6 hours ago, 4x13 said:

I get there are limitations, and I am by no means an expert. I was trying to get a distance of approx 3-4 miles.

The cable length is about 75'

 

 

I apologize if I missed it, but 75 feet of what kind of cable?  75 feet of the wrong cable will consume most of the output power before it ever arrives at the antenna.

Something you might want to try, even if just temporarily as an experiment, is to mount the RT-97 on the mast just below the antenna with a short jumper between it and the feedpoint.

[4x13]

The cable is Gel filled RG-11.

I will try the repeater just attached to the antenna and see the results.

Wat signal level would I want to see at the antenna?

[Sshannon]

So RG11 truly is 75 ohm cable, but that is not terrible.  It just means you’ll never get the VSWR below 1.5:1.  
Losses are 2.65 dB over 100 feet. That’s about the same as LMR400. 
Measure your power output at both ends of the cable and you’ll really get an accurate measurement of how much power you lose in the cable.