SWR seems a bit high...

[WRZY833]

Hello all;

New to GMRS, but long time SWL & radio fan. Just got my ticket and new GMRS radio (KG-1000G Plus), Surecom SWR meter and Bingfu car antenna (460 to 470 MHz). I figured I would try hooking these together to try everything out before the "Big" antenna arrives. On lower channels, I'm getting an SWR of 5.6 and on upper channels (15 -18) I'm getting a reading of 2.59.  I was thinking that with everything kind of "Matched", I'd be down around 1.5. Any Ideas as to why and how I can lower the SWR? I don't want to damage a brand new unit. The cable coming out of the antenna is about 3M long, it's attached to the SWR meter and then a 2FT length of coax connects to the transmitter. Cable is all RG-8X, 50 ohm.
Thanks for your assistance!

Ron,
WRZY833

[SteveShannon]

15 minutes ago, WRZY833 said:

Hello all;

New to GMRS, but long time SWL & radio fan. Just got my ticket and new GMRS radio (KG-1000G Plus), Surecom SWR meter and Bingfu car antenna (460 to 470 MHz). I figured I would try hooking these together to try everything out before the "Big" antenna arrives. On lower channels, I'm getting an SWR of 5.6 and on upper channels (15 -18) I'm getting a reading of 2.59.  I was thinking that with everything kind of "Matched", I'd be down around 1.5. Any Ideas as to why and how I can lower the SWR? I don't want to damage a brand new unit. The cable coming out of the antenna is about 3M long, it's attached to the SWR meter and then a 2FT length of coax connects to the transmitter. Cable is all RG-8X, 50 ohm.
Thanks for your assistance!

Ron,
WRZY833

First, don't necessarily trust the SWR reading from the Surecom.  It might be rights, but there are reports of them being incorrect.

An antenna analyzer will tell you whether your antenna has a reasonable SWR in the 462-467 MHz.  Once you know about the antenna, then test the combination of the cable and antenna.

Second, are you testing with the antenna connected to the car the way it's designed to be?  The simple act of raising an antenna, or placing it on a ground plane, or standing beside it, can drastically affect the SWR.  

Third,  What is the SWR on the higher repeater channels (23-30?) 

Finally, welcome to the forums!

Steve

[WRQC527]

1 hour ago, WRZY833 said:

Bingfu car antenna

Can you tell us exactly what Bingfu antenna? (Link to it if possible.) SWR readings of 5.6 and 2.59 are way too high, even for a somewhat inaccurate meter. (Although it is possible your meter is defective.) Normally you get those kind of high readings with damaged coax, loose connections, defective antennas, the wrong antenna, bad or non-existent grounding, that kind of thing. 

[WRZY833]

@Sshannon ; Thanks! I think sometimes I get too excited with the new toys, that we forget the obvious...Like the missing ground plane because I was just setting this stuff up in my den, and thought a file cabinet would work well enough... probably not! I will test this out on the minivan when I get the chance, and have also ordered an antenna analyzer this afternoon. Will try to remember post my findings later. Also just received my base antenna (Harvest BC200 460-470Mhz 6.5dBi 200W Tunable GMRS UHF Base Antenna) earlier than expected! Will set that up in a more professional manner. 
 

@WRQC527 ; Yeah... It's all brand new cable and connectors. I did not ohm out every piece, but I did visually inspect all of the solder connections (Being employed in the electrical field, I know it sometimes happens!). Looking over the specs of the Binfu antenna, it is listed as "Bingfu Ham Radio Vehicle Car Mobile Radio Antenna Dual Band VHF UHF 136-174MHz 400-520MHz Magnetic Base PL259 Male Antenna for BTECH ICOM Kenwood Midland Yaesu TYT AnyTone Amateur Radio Two Way Radio" I think I may have been thinking of the specs of my purchased "Base" antenna as opposed to what the specs were for the mobile antenna. I'm inclined to think now it may have been a problem with the lack of ground plane / counterpoise and overall quality of the Surecom SWR meter. 
Thanks for your input on the matter, as I'm certainly going to reinspect the cables and connectors.
 

 

 

[WRQC527]

3 hours ago, WRZY833 said:

Bingfu Ham Radio Vehicle Car Mobile Radio Antenna Dual Band VHF UHF 136-174MHz 400-520MHz Magnetic Base PL259 Male Antenna for BTECH ICOM Kenwood Midland Yaesu TYT AnyTone Amateur Radio Two Way Radio

If it's this one, it makes sense that it's giving you high SWR readings. While it says it's compatible with all these different radios and frequencies, the truth is that it would be a Modern Marvel like you would see on The Discovery Channel if an antenna really did cover all those frequencies without being cut or otherwise adjusted. It also specifically says ham radio dual band, which alone makes it sort of incompatible with GMRS. Since ham radio UHF frequencies fall into the 420-450 Mhz range, while GMRS is in the 462-467 Mhz range, it's tough to get an antenna to resonate on both GMRS and ham frequencies.

https://www.amazon.com/Bingfu-Antenna-136-174MHz-400-520MHz-Magnetic/dp/B08TGZN9ZG