SWR of 1.75, can i do better or leave it as is?

[TxHunter777]

Hello All!

New to GMRS and having a blast learning and getting gear together. I recently did a install on Gen 3 Tacoma and I am getting a SWR of 1.75. Below is my build. Looking for some suggestions on how to get the SWR a bit lower, or being what it is, maybe just accept the 1.75 and call it good. Appreciate all suggestions!

 

Equipment Utilized:

Btech GMRS50-Pro - https://baofengtech.com/product/gmrs-50pro/

Midland MXTA24 NMO - https://www.amazon.com/dp/B0842B1WFS

MIdland MXTA26 Antenna - https://www.amazon.com/dp/B084BPXNC5

Ditch Light Bracket - https://www.amazon.com/dp/B0FG7P4DWY With a 3/8" Stainless Steel washer for fitment. 

Surcom Sw-102S - https://www.amazon.com/dp/B01M7QPXEY

 

NMO Mount to Ditch bracket. Recognize the antenna is not perfectly straight up and is at an angle, I'll try to figure out how to get this mount more straight up, but the way my ditch light bracket is, this may not be easily achievable. 

 

 

 

 

I then ran it across the engine bay and then into the cabin through a gromet. 

 

Both the power and NMO cable were tucked under panels.

 

I then created a mount for the BTECH GMRS50-PRO and connected everything behind the drivers side backseat storage. 

 

 

 

Current readings on meter.

 

Once BTECH releases their Mic extension, i will run the mic extension wire from the back panel to the front drivers seat, so i can control the whole radio via the BTECH mic remote. 

 

Thanks!

[SteveShannon]

Try it on different channels. See what the SWR is on the channels you transmit on the most. Don’t forget the 467 MHz main channels. 
To answer your other question, you can tune the antenna by lengthening or shortening it. Changing the location of the mount can also affect the SWR. Antennas have a dip at a single frequency where they’re tuned best. An antenna analyzer helps you know whether the antenna is too long or too short. There’s nothing wrong with 1.75:1. 

[Jaay]

As Steve said, 1.75 vswr is Negligible. Getting your antenna UP over the body of your vehicle would likely lower your reading, but 2.6 watts reflected, according to your device is not harmful.

[Lscott]

10 hours ago, TxHunter777 said:

Hello All!

New to GMRS and having a blast learning and getting gear together. I recently did a install on Gen 3 Tacoma and I am getting a SWR of 1.75. Below is my build. Looking for some suggestions on how to get the SWR a bit lower, or being what it is, maybe just accept the 1.75 and call it good. Appreciate all suggestions!

 

Equipment Utilized:

Btech GMRS50-Pro - https://baofengtech.com/product/gmrs-50pro/

Midland MXTA24 NMO - https://www.amazon.com/dp/B0842B1WFS

MIdland MXTA26 Antenna - https://www.amazon.com/dp/B084BPXNC5

Ditch Light Bracket - https://www.amazon.com/dp/B0FG7P4DWY With a 3/8" Stainless Steel washer for fitment. 

Surcom Sw-102S - https://www.amazon.com/dp/B01M7QPXEY

 

NMO Mount to Ditch bracket. Recognize the antenna is not perfectly straight up and is at an angle, I'll try to figure out how to get this mount more straight up, but the way my ditch light bracket is, this may not be easily achievable. 

 

 

 

 

I then ran it across the engine bay and then into the cabin through a gromet. 

 

Both the power and NMO cable were tucked under panels.

 

I then created a mount for the BTECH GMRS50-PRO and connected everything behind the drivers side backseat storage. 

 

 

 

Current readings on meter.

 

Once BTECH releases their Mic extension, i will run the mic extension wire from the back panel to the front drivers seat, so i can control the whole radio via the BTECH mic remote. 

 

Thanks!

That's a nice neat installation! I like it when people post stuff like this. Good material to reference for ideas.

[WRYZ926]

Anything under 2.0 is okay.

Definitely check the SWR on the repeater channels (467 MHz) as they will have a different SWR compared to the 462 simplex channels. As others have mentioned, there will be a curve to the SWR. Generally 467 will be higher or lower than 462 depending on if the antenna is short or long.

The best I did was when tuning a Tram 1174 for GMRS. I got the SWR down to 1.4 on 467 and 1.2 on 462. Yes I could have kept trying for the perfect SWR but it wasn't worth the time and effort. My two Comet 2x4SR antennas are at 1.7-1.8 on 467 and 1.4-1.5 on 462. Again that is good especially considering the SWR is at 1.8 or less on the other bands that the 2x4SR works on.

While a Surecom will work to tune antennas, you will have to check multiple times across the frequency/channel range to find where the SWR is high or low. This is where a NanoVNA or antenna analyzer comes in handy. They will do a sweep and show the high and low spots.

[TxHunter777]

Ran some channels SWR, is as follows. Was not able to connect to 467 repeater yet, so I will have to figure out how to do that.

Channels:

1 - 1.54

2 - 1.55

3 - 1.55

15 - 1.73

16 - 1.73

17 - 1.73

22- 1.73

23 - 1.6 

[WRYZ926]

You can still check the SWR on repeater channels even without actually connecting to a repeater.  And you don't need to worry about tones when testing SWR. Just say your "call sign testing" just in case. 

[TxHunter777]

I think I will have to program my unit then (still learning how to use it) as the only 467 mhz channels that are pre-programmed are 8-14 which the unit will not transmit on. Will do some more research and report back ! 

Thanks!

[dosw]

Just wait until you try to find one antenna that works on that mount, that covers 2m, 70cm, and GMRS. You'll be quite happy with anything <2.0:1.

 

And yes, it'll work fine.

[SteveShannon]

1 hour ago, TxHunter777 said:

I think I will have to program my unit then (still learning how to use it) as the only 467 mhz channels that are pre-programmed are 8-14 which the unit will not transmit on. Will do some more research and report back ! 

Thanks!

Won’t it transmit on RP15-RP22 (aka 23-30), the repeater channels?