FRS Inter-Species Radio Brands

[echo3whiskey]

Current Situation: I have a 3M and a Motorola radio that I would like to be able to use together.

3M Equipment: Peltor LiteCom Pro III (MT73H7A4D10NA). According to the manual it has capabilities in the FRS (1-14 Analog), GMRS (15-22 Analog), FRS (23-36 DMR), GMRS (37-44 DMR). For simplicity sake, let's say I am on FRS Channel 1, 462.5625MHz, Analog Modulation.

Motorola Equipment: Talkabout T631. Capabilities: GMRS/FRS (1-7), FRS (8-14), GMRS (15-22). It doesn't specify Analog, DMR, etc...

When I transmit Motorola >> 3M the 3M picks it up faint-fair. When I transmit 3M >> Motorola I hear a lot of static and barely audible voice that sometimes gets a little better or worse. Just not consistent. I have tried it over a few of the frequencies, and the experience differs very slightly - but still basically the same.

When I use the 3M to another 3M it is fine. I don't have another Motorola to verify it is perfect. I know that when I Tx on any channel with the 3M the Rx indicator on the Motorola picks up right away.

Both units have a couple of sub-channel modes - but I have those on zero or disabled to the best of my ability.

Usage: I will be in an environment where everyone else has the 3M gear. I also have the 3M unit. I wanted the flexibility to add on the Motorola radio so I could use it instead of the headset - depending on what I am doing. For instance, if I am in a quiet area, I would rather use the Motorola and give my head a break from a 12-hour day of the 3M squeezing my head like an orange.

I noticed that the 3M manual has some additional features on the *NA models (which mine is): Continuous Tone Coded Squelch System (CTCSS) and Digital Coded Squelch (DCS). The Motorola doesn't mention having those features - which are getting over my head regardless.

Anyone think of anything I am missing, or maybe even an explanation so I can just quit fooling with it?

 

[nd5y]

Continuous Tone Coded Squelch System (CTCSS) and Digital Coded Squelch (DCS) are tone squelch. It prevents you from hearing other radios that don't transmit the same tone/code. Motorola calls it PL and DPL but on most consumer type FRS radios it is usually called "sub channels" or "privacy codes". If you can hear anything at all then that is not an issue.

Some radios have audio compandering (compression/expansion), noise cancellation or other audio processing that can cause problems with other radios that don't have it or have it disabled. I would check that first.

FRS is narrowband FM and some GMRS radios are wideband FM on some or all channels. That could cause audio level problems if all the radios aren't the same.

None of the above should cause "static". That is usally due to weak signal levels but could also come from bad or intermittent connections in cables, plug in accessories or antennas, or bad internal components.

 

[iMONITOR]

Some radios have audio compandering (compression/expansion), noise cancellation or other audio processing that can cause problems with other radios that don't have it or have it disabled. I would check that first.

Correct, my Wouxun KG-935G Plus GMRS radios have that speech companding feature. It makes a noticeable improvement when used on both ends. The KG-935G allows you to turn companding off when communication with other radios that do not have that feature.

The KG-935G can switch between narrow and wide band as well!

 

[sallen07]

Motorola Equipment: Talkabout T631. Capabilities: GMRS/FRS (1-7), FRS (8-14), GMRS (15-22). It doesn't specify Analog, DMR, etc...

FRS and GMRS are analog by definition.

When I transmit Motorola >> 3M the 3M picks it up faint-fair. When I transmit 3M >> Motorola I hear a lot of static and barely audible voice that sometimes gets a little better or worse. Just not consistent. I have tried it over a few of the frequencies, and the experience differs very slightly - but still basically the same.

How close are the two radios? Are you holding one in your hand and the other is on the desk in front of you? If so then you are probably desensing the receiving radio. Get a helper to take one of them outside, or a couple hundred feet away and try your test again.

 

[mmckenna]

FRS and GMRS are analog by definition.

Peltor seems to have missed the message on that, and somehow got it through FCC type acceptance (not really that surprising).

 

[sallen07]

Peltor seems to have missed the message on that, and somehow got it through FCC type acceptance (not really that surprising).

Ugh. Missed that part. Ick.

 

[RFI-EMI-GUY]

Are you sure the radios are on same frequencies?
Read the manuals carefully and determine the exact frequency.

Having one radio on 462.6125 and another on 462.6375 or even 467.6125 may result in hearing a weak barely discernible signal.

 

[ramal121]

Peltor headsets have fully programmable UHF radios for part 90 service. I don't think they have a default frequency line up that includes FRS/GMRS channels. Where do you see this in the user manual??? If they do then it was requested by whoever ordered the headsets.

I think that whatever channel line up that is programmed into them doesn't match what is in the Motorolas. I think you are just busting squelch because you are using them too close together and just getting static. Is there any way to actually find out how the headsets were set up?

Peltor headsets are professional pieces of kit at $1K a pop and to expect them to match consumer grade equipment off the shelf for a few Starbucks cost is a bit of a stretch.

Even though they have DMR capabilities, putting that mode on FRS/GMRS channels is a bit of a no-no.

 

[mmckenna]

Peltor headsets have fully programmable UHF radios for part 90 service. I don't think they have a default frequency line up that includes FRS/GMRS channels. Where do you see this in the user manual??? If they do then it was requested by whoever ordered the headsets.

They do sell a model that is pre-programmed with FRS channels.

Even though they have DMR capabilities, putting that mode on FRS/GMRS channels is a bit of a no-no.

And for some reason it includes DMR on some of the FRS channels. Once again, the FCC paying attention….

See the photo on this post: DMR on FRS/GMRS frequencies

 

[ramal121]

Huh, didn't know that. Must be like Ritron. If you don't specify you get plain jane FRS/GMRS. Shady, but oh well...

Wonder if they even stick to the FRS rules.

 

[hp8920]

Authorizing TCB for the 3M PELTOR WS LiteCom PRO III: EMCCert Dr. Rasek GmbH, Stoernhofer Berg 15, 91364 Unterleinleiter, Germany

German certification strikes again!

Pretty sure it's a CCR jammed into an earpiece anyway.

 

[mmckenna]

Hmmm, I see a pattern.

 

[Cameron314]

This is what they show as their US and CA model freq.