Using two-way radios at theme parks for non-Ham Radio consumers: Difference between revisions

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#MURS also unlicensed, with 2W power limit. There are very few MURS certified radios on the market and it's VHF.
#MURS also unlicensed, with 2W power limit. There are very few MURS certified radios on the market and it's VHF.
#GMRS is UHF. You need to get a license from FCC for the modest fee and then you can transmit up to 50 watts on simplex and repeater GMRS channels. You also need GMRS type-approved radio to use these channels legally.
#GMRS is UHF. You need to get a license from FCC for the modest fee and then you can transmit up to 50 watts on simplex and repeater GMRS channels. You also need GMRS type-approved radio to use these channels legally.
Note from the FCC Rules Part 95-1791: "Effective September 30, 2019, no person shall be permitted to manufacture or import, sell or offer for sale any radio equipment capable of operating under both this subpart (GMRS) and subpart B (FRS) of this chapter."


So it seems GMRS is the obvious way to go. Here where the problem begins.
So it seems GMRS is the obvious way to go. Here where the problem begins.

Revision as of 16:09, 16 March 2022

If you frequent theme parks such as Disney, Sea World or Dollywood you know cell phone usage can be a challenge.

I suggest using two-way radios to conserve battery power for your phones which also serve as your camera right?

If you and your part are licensed Amateur Radio operators stop here and use your hand-held (a.k.a. "HT"). If you would like to become licensed as a Technician Class which is perfect for this use-case visit http://www.arrl.org/getting-licensed. Advantage here is power and clear frequencies. You can often use 5 watts or more legally and well made radios that support that.

If you are not interested in getting a Ham Radio license here are your remaining options:

You will need about 5 watts honestly if the park if your normal sized theme park. Add to terrain Dollywood in particular is on the side of a mountain range and very hilly. You may need even more power to reach say the parking lot to the opposite end of the property. UHF cuts through mountains and hills better than VHF frequency range. If you look at Dollywood's radio system it is all UHF. See https://www.radioreference.com/apps/db/?aid=1755.

There are four classes of two-way radios available for your average consumer outside of Amateur Radio (See FCC Rules & Regulations Part 95: CB, FRS, GMRS and MURS

  1. CB radio is allowed 4 watts and although they make CB hand-helds they are all AM modulation (although that is about to change) and in the 27 MHz frequency range and typically bulky in size thus in most cases CB radio is ineffective at a theme park.
  2. FRS does not require a license but is limited to 500mA (as of 2017 the FCC allow up to 2W of power on all current FRS channels, including those shared with GMRS however 2W radios are slow to emerge on the market). But still 2 watts in most cases is probably not enough power particularly for Dollywood unless you are all inc lose proximity all the time. FRS is all VHF frequency range.
  3. MURS also unlicensed, with 2W power limit. There are very few MURS certified radios on the market and it's VHF.
  4. GMRS is UHF. You need to get a license from FCC for the modest fee and then you can transmit up to 50 watts on simplex and repeater GMRS channels. You also need GMRS type-approved radio to use these channels legally.

Note from the FCC Rules Part 95-1791: "Effective September 30, 2019, no person shall be permitted to manufacture or import, sell or offer for sale any radio equipment capable of operating under both this subpart (GMRS) and subpart B (FRS) of this chapter."

So it seems GMRS is the obvious way to go. Here where the problem begins.

There are very few high power (>4W) handheld GMRS approved handheld radios on the market (and none that support repeater frequencies). There were a few high quality commercial Part 90 radios that were also certified for 95a (GMRS) but those are discontinued long time ago.

The product in question is one of the few ones that produces honest 5 watts - confirmed on FCC web site by looking up FCC ID and relevant lab measurement reports.

Sounds great on paper.

Some guidance:

  1. Setup of the privacy codes on the first 22 channels is simple enough. What are the rest of the advertised 50 channels there is no description, but you can find discussion online: Apparently these are the same frequencies (have to be - there are only so many GMRS/FRS frequencies allocated) with pre-set privacy codes. No word about what codes and what frequencies in the user manual. It's a gimmick feature to show "more channels" than the competitors and likely those will work with other Midland radios out of the box. I don't like such marketing stunts - but whatever. Not a big deal.
  2. Receiver is very noisy. Much noisier than my other commercial handheld's one. This will limit useful range by raising noise floor. Not good.
  3. Radio seems to indeed transmit 5 watts with fairly decent range (comparable with that of my other real part 90 5W transceiver). But only when using included battery pack. This is crucial "but" never mentioned anywhere.

The battery pack is 5 NiMH AAA rechargeables sealed together. (Note - 5, not 4). Unfortunately the capacity of the pack is 700mAh and according to my measurements the radio consumes average of 42 mA in standby with display off. This makes it only last for 16 hours if you don't transmit (it lasted only 8 hours in my test). Not much at all. What makes it worse - charge time is 12 hours (charging current was well under 150mA). And no, you cannot charge (spare) battery pack while using the other one - it must be charged while in the radio. What's even worse - they include automotive charger in the box - implying that you can quickly recharge the units while driving. Who is driving for 12 hour straight!? This is absolutely useless and misleading feature. So in the current form the radio is unusable for a long backpacking trips - unless you buy charge and bring extra battery packs - 2 per radio per day.

4. But wait you say - you can power the radio with AA batteries!. Yep. Sort of. You can put 4 (not five) AA batteries. And this would of course provide radio with less voltage. Perhaps they engineered it well to properly work on a range of input voltages? Nope. Using AA batteries (or AA NiMH rechargeables) reduces output power to about 2.0 - 2.5 watts. There is no indication of that happening (except the reduced range, and current consumption - which I measured) - the display still shows "H" for high power. And it is not mentioned anywhere in the documentation (or I overlooked the fine print somewhere). This way you get very log battery life - you can find AA batteries with capacities well over 2000mAh - but now the feature you bough the units for and that is advertised in huge letters - 5W output -- does not apply anymore. You got noisy, weak set of walkie-talkies.

So, to summarize:

  1. Unusable battery life - you either use battery pack with very short life and get your 5W transmit power or use batteries and get 2W.
  2. Noisy receiver - limits range by increasing noise floor.
  3. Unacceptably long charging time - 12 hours. Included car adapter is therefore useless and is pure gimmick feature.
  4. Bogus channels 28 channels (after official 22 FRS+GMRS ones) with unknown frequencies or programming that cannot be changed. Another gimmick.