I just recently purchased a new MX-850 to replace an older MX-850, which still works perfectly fine, but after years of use, the buttons have started to fade and there are many dings and scratches on the case.

Anyhow, I've noticed that the new remote (used in RF mode with multiple MRF-300 base stations) is not as consistent, compared to the older remote. With the older remote (which was purchased around 2006 or so) out of every 100 to 200 button presses, maybe one command would not be picked up by the base station.

But now, with the newer remote, it seems (just estimating here) that out of 100 button presses, about 5-10 commands are missed on average. I also noticed that the range is much shorter now. I am able to use the older remote from over 30 feet away, but I have to be within 15-20 with the new one.

Is this a result of the newer MX-850 having different RF circuitry than its older counterpart? Shorter internal antenna?

Or is it because the new one uses narrow band, and must be used (for best results) with the newer MRF-350's? If so, can the external antenna on my existing daisy-chained MRF-300s be replaced with the narrow band antenna from an MRF-350 to achieve better results?

Thanks for your help.

It's the narrow band RF of the new remote. All URC remotes manufactured after 2008 are narrow band. You need a new RFX250 antenna on your base station, but that will make your old remote obsolete too.

Your assumption seems correct to me. We've noticed that in the past when changing out legacy remotes that were utilizing the mrf-300. And yes, you can swap your existing antenna for the new narrowband version, part number is rfx-250. If you're using cat5 or similar to extend the antenna, note that the molex connector pinouts on the base and rfx differ. Also, do not use 3.5mm on one end and molex on the other. Stick with one or the other on both.

Thank you for your responses.

So, just to be sure here. I am currently not extending the antenna with Cat5. I'm just using the supplied cable that came with it. Is it just a matter of unplugging the cable (from the antenna end) and popping it into the RFX-250?

The existing cable is fished through the cabinetry and if it is not necessary, I wouldn't want to go through the hassle (although minimal) of passing a new cable through.

Oh, by the way. Will the range be improved (comparable to the older remote)? Or does the narrow band RF just have shorter range?

You can use the same miniplug cable with the new antenna, that hasn't changed.

You perceived range might be longer because the antenna is rejecting wideband noise. Your mileage may vary.

Yes. I was just making you aware of the pinout if you were or plan to extend the antenna farther since your existing antenna does not have a molex connector. Plug and play with your existing setup.



Range should be slightly better than your old setup but that's really a factor of the systems' environment and antenna placement. The real purpose of the rfx-250 is the narrow band for filtering out interference in the 418 or 433 MHz channel which amongst other things can reduce range and reliability.

Thank you. I appreciate all your responses.

UPDATE: Went to the store today and picked up an MRF-350. Swapped out the new RFX-250 with my existing antenna module and everything is working just fine.

Range appears to have improved (over 60 feet) with all remotes (pre-2006 MX-850 works, along with 2004 MX-3000) and the response is noticeably better. I didn't actually do a count, but after fiddling with numerous button presses, I would guess that less than 1% of commands are missed by the RF base station. (About the same as older setup).

One other thing... Is a MRF-300 basically identical to a MRF-350 in circuitry? Are there any advantages to swapping out the base stations? Or, with the RFX-250 attached to the 300, will it function exactly the same way?

If there's a difference, I guess I'll eventually get around to swapping them out. Otherwise, if it aint broke...

Thank you all again for your help.

Don't waste your time, keep it as a backup.

The MRF-300 and MRF-350 base boxes are identical. The antenna modules are what are different between those two models.

One thing I find interesting...

I referred to the Narrow Band Compatibility thread and noticed that a pre-Nov. 2006 MX-850, as well as an MX-800 (any year) should not work with the narrow band Base Stations.

However, my older MX-850 and MX-800 (which I brought out from storage) work just fine with the RFX-250. As for my MX-3000, I had originally thought that it was pre-cutoff, but it wasn't.

Anyhow, it seems that posters from that thread said that their older remotes work just fine, as well, with the narrow band base stations. Why is that? Why would URC say that they wouldn't?

They are all the same frequency it's just the newer ones are less susceptible to interference from being narrower in that spectrum. In your case you have a mixture of 418MHz narrow band and wide band. The wide band remote will work as you've noticed it's just not "as good" as the new models; which is obviously highly subjective.

You also can't fully rely upon information from URC. For instance there are still sales literature sheets in the URC control room for the MRF-350 (which has the narrow band RFX-250 antenna) stating that it is only compatible with MX-3000,
TX-1000, MX-950 and MX-900 remote controls only LOL Uhhh, yeah that's not even close to accurate.

The official word is, older remotes had a lot of "slop" in their RF frequency window, and it's possible to get specific ones that might be broadcasting entirely outside of the new narrow band reception slot.

So the rule of thumb is older remotes will most likely work, maybe even better, but are not absolutely guaranteed to work, or may work worse.