How can I connect my Retevis MA09 High Gain 462~467MHz GMRS Omni-Directional Base Antenna to my Midland MXT 275?

[WSBX980]

I bought the MA09 High Gain 462~467MHz GMRS Omni-Directional Base Antenna to use with my MXT 275 Midland. But, it appears that the connection are different. I am asking what connections are needed and where can I purchase a cable already made up for this.  Thanks

[beerftw]

It is easy step one buy antenna step two ?????? step three profit!

 

  More details would be helpful or atleast pictures would be helpful. But a quick search shows the antenna is a sl16 connector. But more info is better because some antennas were made with different connection types especially if bought off amazon and or counterfeit.

 

  Cable and adapters can be bought from most online suppliers, be specific on how long the cable needs to be and under what conditions the cable will be under. General rule of thumb is to use the minimum amount of cable needed with a little extra depending on if you think you may need to move or adjust it.

[WSBX980]

The cable only needs to be about 20'. So, I am assuming that I will not loose that much gain.

[beerftw]

Quick google search shows a pl-259 connector is needed for the radio side, and pl-259 is among the most common gmrs connectors for antennas. So you would need a sl-16 to pl-259 adapter, and from a quick search the sl-16 is the metric version of the pl-259, so you are trying to connect a european style antenna to an american radio, which adapters are made for.

[beerftw]

1 minute ago, WSBX980 said:

The cable only needs to be about 20'. So, I am assuming that I will not loose that much gain.

For a safe bet 50 ohm uv resistant coax would be a safe bet. There are many coax types but 50 ohm is considered low loss, and uv resistance is important. Lm400 coax was reccomended to me here as a good low loss coax. There are less resistant coax types but water intrusion or interference may be a problem, and to stick with the keep it simple stupid principle or kiss, if you are asking these questions you should stick with tried and true 50 ohm uv resistant coax types.

 

  If it needs to be 20 feet get 25 feet, not much more loss but gives you some wiggle room for adjustments, nothing worse than measuring 20 feet to realize it would have worked 2 feet over to the right better.

[WSBX980]

I found that the Antenna is a SL16 and the Midland is a SO-239. 

Is the PL-239 the same as a SO-239?

[WSBX980]

So, where would a good place be to acquire such a set up?

 

And thanks for the input.

[beerftw]

18 minutes ago, WSBX980 said:

I found that the Antenna is a SL16 and the Midland is a SO-239. 

Is the PL-239 the same as a SO-239?

pl259 is the male end so239 is the female end, so you need a pl259 connector to plug into your radio.

[WRTC928]

Isn't SL16 another term for a UHF connector? if so, no conversion is needed. The antenna will have a PL259 and the radio will have an SO239. You can plug them directly together. Have you (carefully) tried to see if they fit together?

[beerftw]

41 minutes ago, WRTC928 said:

Isn't SL16 another term for a UHF connector? if so, no conversion is needed. The antenna will have a PL259 and the radio will have an SO239. You can plug them directly together. Have you (carefully) tried to see if they fit together?

Sl16 is the metric version of the pl259, depending on thread tolerance sometimes they fit and sometimes they need adapters. For example on thread tolerance I have a soviet gp5 gas mask that takes 40mm cartridges, but soviet carts were different than nato, and would not fit except the french 40mm carts that used the nato thread pitch but left it just loose enough it would thread on to the soviet one while still working with nato ones.

  Imagine the same thing with the sl16, it depends on if the maker make the threads to tight tolerances or left them a little loose incase someone was going to use it on a non metric radio connector.

 

  Also if anyone asks why I have a gas mask or which filters fit and about thread tolerance, during that whole mandatory mask crap from covid I had plenty of fun between the gas mask and the plague doctor mask.

[WRTC928]

37 minutes ago, beerftw said:

Sl16 is the metric version of the pl259, depending on thread tolerance sometimes they fit and sometimes they need adapters. For example on thread tolerance I have a soviet gp5 gas mask that takes 40mm cartridges, but soviet carts were different than nato, and would not fit except the french 40mm carts that used the nato thread pitch but left it just loose enough it would thread on to the soviet one while still working with nato ones.

  Imagine the same thing with the sl16, it depends on if the maker make the threads to tight tolerances or left them a little loose incase someone was going to use it on a non metric radio connector.

Ah, okay. Not quite as simple as my Google search led me to believe.

37 minutes ago, beerftw said:

  Also if anyone asks why I have a gas mask or which filters fit and about thread tolerance, during that whole mandatory mask crap from covid I had plenty of fun between the gas mask and the plague doctor mask.

I have both of those and a T-shirt that says, "Trust me. I'm a plague doctor."

[WSBX980]

Yes, they don't fit.

So what would the connector be called?

[beerftw]

6 minutes ago, WSBX980 said:

Yes, they don't fit.

So what would the connector be called?

You need to find an sl16 to pl259 adapter, likely the thread tolerances are just tight enough where it will not thread at all.

[WRZK526]

I put my MXT 275 in my house attached to an antenna using PL259 male to male coaxial and it went together no problem. If they don't go together you may have a bad connector. 

[LeoG]

I've dealt with 3 of the MA09 antennas and all 3 of them were just standard UHF connectors.  SO239 connector on the antenna requiring a PL259 end on the coax.

I went to the Retevis site and it does say it's a SL16 connector.  I got my antenna when I ordered a RT97S repeater.  It had a SO239 connector on the repeater and antenna.  The coax they gave me with my order had PL259 connectors.

Possible the new version has the new connector.

[WRTC928]

Maybe the easiest solution would be to replace the connector.

[SteveShannon]

 

On 2/4/2026 at 7:14 PM, WSBX980 said:

I bought the MA09 High Gain 462~467MHz GMRS Omni-Directional Base Antenna to use with my MXT 275 Midland. But, it appears that the connection are different. I am asking what connections are needed and where can I purchase a cable already made up for this.  Thanks

Contact Retevis customer support.

[LeoG]

Yup, maybe they sent you the wrong end.  It's made in chyna so it's possible you got sent the otherworldly connection instead of the US compatible connection.