High SWR Retevis MA09 base antenna

[WSBQ643]

So, I bought the RT97 which came with the MA09 base antenna. Hooked everything up including my SWR meter and all was perfect. SWR 1.0

The repeater is tuned and apparently the antenna for 462.6500. When I change the antenna over to use on my HT I get an SWR reading of 2.5. At first I could not figure this out but it dawned on me the antenna was not tuned to transmit on 467 which is another repeater I was wanting to hit. I checked the Retevis website and tried googling to find a turning chart for the antenna like the one used with the Tram 1486 but could not find one. 

So am I just going to have to purchase a new base antenna or is there a way to tune this one if I decided to use it for a base antenna instead of for the repeater? 

 

[Guest]

Unlesss they tuned your antenna in the factory the ma09 is tuned for all gmrs frequencies.   You may have something else going on like the adaptor from the ht to the coax.  
 

personally I’d run 2 antennas.  I’m not a fan of anything retivis but I’d keep the repeater exactly how it came.  
 

then buy a comet 712efc with some lmr400 and mount it as far away from the other antenna has you can and at a different height preferably 12-14” higher or lower then the other one.  
My 5w ht with the comet does 40-50 miles.  My 20w base statin does over 200 miles with the comet.  

[WSBQ643]

Quote

I appreciate your response. I will look into the Comet you suggested. As a footnote when I change to simplex freq's at 462 the SWR's are perfect so I would assume they tuned this specifically for the repeater. 

 

[SteveShannon]

13 hours ago, WSBQ643 said:

So, I bought the RT97 which came with the MA09 base antenna. Hooked everything up including my SWR meter and all was perfect. SWR 1.0

The repeater is tuned and apparently the antenna for 462.6500. When I change the antenna over to use on my HT I get an SWR reading of 2.5. At first I could not figure this out but it dawned on me the antenna was not tuned to transmit on 467 which is another repeater I was wanting to hit. I checked the Retevis website and tried googling to find a turning chart for the antenna like the one used with the Tram 1486 but could not find one. 

So am I just going to have to purchase a new base antenna or is there a way to tune this one if I decided to use it for a base antenna instead of for the repeater? 

 

You really don’t have to buy another antenna. An SWR of 2.5 isn’t really very high and isn’t going to cost you much. Most people don’t understand how little an SWR of 2.5 means. As an example, the SWR in your cell phone may be around 4 or 5. 
Just try your antenna and see if it works for you. 
At an SWR of 2.5 82% of your power goes out of the antenna without being reflected, but that other 18% is reflected back to the transmitter where it’s reflected back to the antenna again. Then 82% of that portion is radiated and 18% of the reflected power is reflected again. That happens over and over until all the power goes out the antenna or is absorbed as loss by the coax cable. 
 

[OffRoaderX]

13 hours ago, WSBQ643 said:

I get an SWR reading of 2.5

as @Sshannon, 2.5 is just fine.. Stop overthinking it and enjoy your repeater.

[CudjoeCane]

I own a Comet 712EFC.  It is also the antenna our clubs (joint effort) used on three repeaters in the lower Florida Keys.  I also own a pair of Retevis MA 09s.  I've donated one for use on a fourth Florida Keys repeater. 

Both of the ones I personally used worked well right out of the box.  Each gave me a flat SWR across GMRS when first put together and tested on a tripod mast with RG-8X, RG-213 and LMR 400.  Both reacted to changes in coax type, length, connectors, mounting locations, etc.  Not surprisingly, the 712EFC is the better performer, but either can work well for you.  

[LeoG]

I have the Retevis MA-09 antenna and so far the SWR has been 1.01 on both my HT and RT97S at both frequencies 462 and 467Mhz GMRS bands.  Not exactly sure how they accomplish this but I've checked on many of my HT's and the repeater in several different antenna placements. 

[SteveShannon]

6 hours ago, LeoG said:

I have the Retevis MA-09 antenna and so far the SWR has been 1.01 on both my HT and RT97S at both frequencies 462 and 467Mhz GMRS bands.  Not exactly sure how they accomplish this but I've checked on many of my HT's and the repeater in several different antenna placements. 

A long run of lossy coax will always result in lower SWR measured at the radio.

The choice of radio should have very little effect on the actual SWR. 

Some SWR meters won’t detect reflected power well at low power levels. 
Or maybe it’s just a well tuned antenna. 

[LeoG]

I am running 50' of RG8/U coax right now.  It's all I have until the good stuff gets here probably today.  And I've heard that low power can make it harder for the meter to do it's job properly.  HT says 4-4.5 watts and the repeater says 6.4 watts.  Both falling into that low power category.