XPR7550 & NMN6274

[KN1IGHT]

Hi all,

I have been looking at purchasing an NMN6274 to pair with my XPR7550, however I am finding conflicting information on what firmware the XPR needs to be for this mic to work with it, since Moto's site doesn't list the XPR7550 as compatible.

In my searching for an answer, I have come across clearly old eBay listings for an NMN6271, which state in the description that the minimum firmware required is R02.40.02 (or later) for the NMN6271 to function properly with the XPR7550 (I'm assuming it's the same for NMN6274).

My XPR7550 is currently on Firmware Version R02.09.00.0001 (has been on this version since I got it) & Codeplug Version 14.00.13
I am/ have been using CPS 16 Build 828 for programming it.

I do have a MOL account & can see & download firmware releases under MyView -> Entitlements -> Software, however none of them are R02.40.02.

I also found 2 threads in my searching, about basically the same topic.
One from 2017: (

Best dmr radio in 2017

Last year I got to looking into dmr and was looking at the cs 750 tyt md380 but money went short and that was about it for that idea. So now I'm back and ready to pull the trigger on my first dmr radio but my question is whats out there now that's better then these 2 radios but around or under...

forums.radioreference.com

)
One from 2022: (XPR 7550 pairing to a IMPRES XP RSM Mic)

The specific post I linked to in the 2017 one basically reiterates what I said above about firmware needing to be R02.40.02 (I am assuming the NMNN6261A in that post is a typo) & then the 2022 one references firmware 2.08 & 2.09, so I basically got 2 questions:

1. Would my current firmware (R02.09.00.0001) allow an NMN6274 to work with the XPR7550?
2. If not, would the most recent firmware release (on 3/15/2022) which is R02.21.01.1005, allow the NMN6274 to work properly with the XPR7550?

I am posting this, before purchasing an NMN6274 & updating the firmware on the XPR.

Hopefully this post was easy to understand.
Thanks in advance to anyone who can help.

 

[hp8920]

R02.40 is basically R02.04, released circa 2014. You are on R2.09, which exceeds that version. It has to do with Motorola switching numbering schemes. They went R02.40, R02.50, then switched to R02.06. Then again, after R02.10, they switched schemes to R02.20, where 20 is the year of release, 2020.

 

[Firebuff880]

Motorola NMN6274 APX XP Remote Speaker Mic, 3.5mm Jack​

No the XPR does not support the 3.5mm jack interface.

 

[K2NEC]

No it won't work, you need the NMN6271. It's a different connector that's not supported on the TRBO series.

 

[hp8920]

Motorola NMN6274 APX XP Remote Speaker Mic, 3.5mm Jack

No the XPR does not support the 3.5mm jack interface.

No it won't work, you need the NMN6271. It's a different connector that's not supported on the TRBO series.

The 3.5 mm jack is on the RSM and lets you plug in an earpiece with a short cord to listen. It has nothing to do with the radio-side interface.

 

[K2NEC]

The 3.5 mm jack is on the RSM and lets you plug in an earpiece with a short cord to listen. It has nothing to do with the radio-side interface.

1. The RSM doesn't have a jack on it, the connector does
2. The connector that attaches to the radio doesn't have a cutout that is required for TRBO radios. It physically will not fit the radio.

 

[KN1IGHT]

R02.40 is basically R02.04, released circa 2014. You are on R2.09, which exceeds that version. It has to do with Motorola switching numbering schemes. They went R02.40, R02.50, then switched to R02.06. Then again, after R02.10, they switched schemes to R02.20, where 20 is the year of release, 2020.

Confusing, but does make more sense now that it's been explained. Thank you

1. The RSM doesn't have a jack on it, the connector does
2. The connector that attaches to the radio doesn't have a cutout that is required for TRBO radios. It physically will not fit the radio.

You are correct. The connector itself has the 3.5mm threaded connector on it.
I also wasn't aware that it wouldn't physically fit. Prior to posting, I just assumed the NMN6271 & NMN6274 connectors were identical, with NMN6274 connector being slightly bigger to accommodate the 3.5mm threaded jack.

Thank you to everyone who answered. I truly appreciate the help, regardless if I replied directly to your post or not.

 

[K2NEC]

Just for a visual, this is the connector on the 6274:

And this is a normal TRBO connector:

Notice how the middle part is cut out on the top part that hooks into the radio. The APX doesn't have or need this middle part to be cut out. But the TRBO does.

 

[KN1IGHT]

Just for a visual, this is the connector on the 6274:

And this is a normal TRBO connector:

Notice how the middle part is cut out on the top part that hooks into the radio. The APX doesn't have or need this middle part to be cut out. But the TRBO does.

I've had my 7550 for a few years now, &, now that it's been pointed out, I do recall noticing that cut out when using my current PMMN4025 speaker mic, but I never even thought about it being something to consider when looking for the 6274.
Since I'm more of a visual person, I do appreciate the pictures to explain/ visually show why the 6274 will physically not work.

 

[MTS2000des]

Notice the prick move, just like the battery notch on the casting preventing certain otherwise compatible batteries from being used. Some of us file down the notch on the housing with a Dremel to overcome this hurdle.

 

[KN1IGHT]

I was wondering about that, if it was possible to modify either the radio, or the mic so they work together, however I’m not to comfortable with the thought of doing that.

Can anyone report/ does anyone know if a PMMN4099 works with the XPR7550?
If I recall, the 4099 has an orange button, 1 programmable one, 3.5mm jack & a high/ low volume toggle.

I recall coming across 1 or 2 threads in the past that say it does work, but cannot seem to locate those anymore. Not sure if they were here on RR, or else where though.

In one of those threads however, I do remember that someone detailed how they opened up the PMMN4099 & modified the internals, so the high/ low volume toggle was actually noticeably louder when it was set to high (prior to the modification, the high volume was barely louder then low).

Will reiterate again, I do appreciate the help & info from everyone.

 

[K2NEC]

4099 works on a 6550, don't see why it wouldn't work on a 7550

 

[scfd4]

4065A works also