Thinking about Radios for your camp? Read Me First!!!

[krazyj]

So, for the the big question:

For an unlicensed operator, what technology should we be using if we need to have portable communications from the beginning of the entrance road to the back of the deep playa?

[GreyCoyote]

MURS, ideally on channels 1,2 or 3.

Edited to add: comms from the end of the pavement to the far side of the event on VHF (or higher) freqs will be tough, regardless of the power. Everything up there is "line of sight", ie, if you can see it, you can talk to it. So height is EVERYTHING. Power, over a couple ofmwatts, means nothing. (Example: I can [and have] hit the ISS in orbit with just 5 watts)

The formula for distance at VHF and higher freqs is this:

Dist in Miles = (square root of Height (in feet)) x 1.23

Hope this helps.

[krazyj]

Will there be any problems using stock portable radio antennas at ground level in BRC, at unlicensed transmit powers?

From my research, it seemed like some combo of those factors would almost ensure some TX problems across the maximum 6 square miles of BRC?

[GreyCoyote]

Get some height. At VHF and above, 100 watts at 5 feet will not be nearly as effective as 5 watts at 20 feet.

Height is EVERYTHING.

Height plus antena gain for the win!

[krazyj]

Thanks for your insight on this!

What kind of range could we expect from a portable-sized antenna, transmitting at 1W (or whatever the unlicensed maximum is) on a MURS channel, strapped to a human down at ground level in BRC?

(I'm evaluating whether MURS radios would, among other reasons, be a reliable (emphasis on reliable) way to radio my campmates, upon my solo arrival to BRC.)

[EGAZ]

What are you calling a "portable-sized antenna"? Got a pic?

Ground level,..... from what GC stated in your other thread, 3-4miles.....

[GreyCoyote]

Assume two walkie talkies each held at 5 feet:

Range each handheld:
:: sqr(5) feet = 2.2
:: 2.2 x 1.23 = 2.7 miles

2.7 + 2.7 = 5.4 miles

Note this is the MAX range under ideal conditions. In the real world comms will start getting flakey about 3-4 miles out on clear, flat ground, and be toast by 5 miles.

[krazyj]

What are you calling a "portable-sized antenna"? Got a pic?

I'm speaking generally to a stock antenna that might come with a handheld radio... so something like a ~7" antenna.

Assume two walkie talkies each held at 5 feet:

Range each handheld:
:: sqr(5) feet = 2.2
:: 2.2 x 1.23 = 2.7 miles

2.7 + 2.7 = 5.4 miles

Ah! Thanks for that formula. I wasn't aware that's how two-way range was calculated.

Note this is the MAX range under ideal conditions. In the real world comms will start getting flakey about 3-4 miles out on clear, flat ground, and be toast by 5 miles.

Hmm ok. So it sounds like my plan to buy 2x portable MURS radios to locate my campmates wherever they may be around the city is out then (thanks to lack of reliable range).

Thank you for the lesson!

EDIT: On second thought, would 2x MURS radios reliably reach each other, if they were TXing from opposite ends of the living area of the city (i.e. that's to say: 9:00 & L <-> 3:00 & L).

By my calculations, that's only 1.4mi between them.

Think MURS from ground level @ 1.4 miles of distance would be reliable?

[krazyj]

Hah, I think my calculations were actually wrong. Looks like the city's living area is closer to 2 miles, end-to-end.

[GreyCoyote]

MURS should work. Put a good antenna on it (something with a little gain instead of a 4 inch rubber ducky) and you should be ok. I've hit a talkie at 5 and G from just off the pavement on 2 meters from a mobile. Was a bit scratchy, but readable. 2 miles should be fine with good radios and an adequate antenna.

[Plugh]

[quote="Just_Joe"][quote="A-RockLeFrench"] Does this mean I have to plug them into a computer to program grew/channel presets into them?[/quote]
Probably not. Programming these (Beofung) radios manually is a PITA, but the learning curve of the software and requirement of a special USB to Serial cable and drivers is probably more of a PITA, especially since you're probably only going to put the 5 MURS channels on it.
[/quote]

The BF-888 is a 70cm (440MHz) only radio. You can't program MURS frequencies into them.

[duckdive]

Newbie here. I'm a builder of Fruition Fantasitco (fruit basket art car).

We'd like to have a couple radios. I've read through the post thoroughly, but I'm a bit confused on one point.

It seems like going the MURS route is recommended. But from what I read, there are only 5 channels. Wouldn't that just be just as congested with all sorts of people talking on it? Or does the code essentially work as a "subchannel" to isolate the conversations?

[Token]

I just love it when folks go to BM and expect anything to be reliable.

That is just crazy.

The biggest gathering of anarchysts (oh the irony) and reliable is wanted?

Sat Phones are the only reliable comms at BM. Or as reliable as the folks paying attention to them, to frame it correctly.

Just let go. Loosen up a bit.

[TT120]

In my experience, all the MURS channels were dead. The FRS and GMRS frequencies had a few people but not very many. Not much radio activity at all. I guess everyone is too busy chasing shiny things or trying to find Daft Punk to be talking on the radio.

[GreyCoyote]

MURS is one person talking, per channel, at a time. FM simplex.

There are PL codes ("Private Line") codes that allow multiple users to use the channel as if it were "private", but this is a serious mis-nomer. PL codes (or CTCSS for Continuous Tone Coded Squelch System, which is a more accurate name for the whole PL thing) just openS the squelch at the receiver when the proper sub-audible tone is received. The practical effect is even if others are on the channel, you only hear what is directed at you.

But its STILL just a party line.

If someone else talks at the same time as you, (with a different PL tone) the result is a mess.

Short answer: yes, there are only 5 channels of MURS. Yes they can become crowded. But lacking a license, thats what you are stuck with. (And may God have mercy on your soul if you trespass in the licensed amateur spectrum, because we WILL find you and we WILL file complaints and you WILL be cited. Just sayin')

[duckdive]

And I'm guess that the bugs also have an effect on the radio transmission. I hope they aren't as bad as last year.

[TT120]

....... (And may God have mercy on your soul if you trespass in the licensed amateur spectrum, because we WILL find you and we WILL file complaints and you WILL be cited. Just sayin')

So much YES here. It's kind of a sport for us and we're good at finding you.

[EGAZ]

Challenge Excepted!!!

Let the Games begin!!

LOL

[duckdive]

You'll never find me... wait... just look for the fruit basket.

[Plugh]

And I'm guess that the bugs also have an effect on the radio transmission. I hope they aren't as bad as last year.

UHF should punch right through bugs. Better yet, jack up the frequency and power and cook the little shits right out of the sky.

[Skuzzy61]

There are two reasons I want my Wife and I to have radios.

1) Emergencies. Whether it is us, or someone else. Yes, we are taking it quite seriously the Playa could kill us.

2) If we get separated, just so we know each other is okay.

I do not envision us using the radios, like phones, to talk to each other.

[GreyCoyote]

Next year, you might consider getting your Tech (ham) license. Just a few really simple questions, and then you can use the local repeaters and APRS. APRS gives you the ability to "track" each other (gps position is automatically reported over the airwaves once a minute on 144.39). Accuracy is within a few feet and it doesnt require her to monitor the radio or even have a conversation with you if she has her hands full.

Next year.

[TT120]

For the record, in an emergency, it is legal to use any frequency necessary, licensed or not.

[Plugh]

For the record, in an emergency, it is legal to use any frequency necessary, licensed or not.

It better be a really darned good emergency, where someone's life is at risk. People have been criminally charged (in other jurisdictions) for keying up on police bands when they determined is wasn't a life-threatening situation.
If you have an emergency on-playa, MURS 5 PL code 11 (97.4) is being monitored 24x7 by the rangers and EMS. They ask the community's restraint from using this channel for casual traffic, despite it being a publicly usable frequency with no license required. Similarly, MURS 4 code 11 is used by art installation teams to get support from the ARTery, and they would appreciate keeping this frequency clear of casual traffic.

Unlicensed options are as follows:
* CB - Works pretty well. Handhelds are available that can talk for a mile or two. You have 40 channels to play in. Your range is pretty much tied to your antenna length. The closer to a 5.5m antenna, the better signal you'll get, but in handhelds, best you'll get is a few inches.
* MURS - Channels 1-3 are available. Probably slightly more congested with traffic than CB. Optimal antenna length is 1 meter. Good luck finding that, and you wouldn't want to carry it around anyway.
* FRS - This is the ubiquitous talkabout. A little handheld plastic box that has a theoretical range of about a mile at 1/2 watt, but that's only on an open playa with nobody else using them. You may be able to use them around camp, and if you're REALLY LUCKY, from camp to the nearest bank of porta-potties. The frequencies here will be slammed with traffic, and you'll be lucky to get a word in edgewise.
* GMRS - Despite being sold in practically every store with claims of 20 miles range (across open playa with no intervening structures or interference), the 8 GMRS frequencies are licensed spectrum. You pay the FCC $65 and your default world extended family can legally use them for 5 years, as long as they give the licensed callsign every 15 minutes and at the end of every conversation. I think you can count on one hand the number of people who follow the GMRS license rules at Burning Man (and pretty much everywhere else). Everyone uses these channels the same as FRS with the same results.

Licensed options:
* Spend a day cramming for the ham technician exam, pay $15 to your local radio club to take the test which is 35 questions randomized from the pool, and get your ham ticket for 10 years. Do the same for each family member who wants to use the radios. Buy a couple of cheap Chinese radios for $25/ea or so and talk all you want in a clear spectrum with nobody else bothering you. Use the repeaters to really extend your range. From the playa, you can connect to the Gerlach IRLP node to talk to people anywhere else on the planet.
* Pay the FCC about $300 for a commercial lease, buy a couple of cheap Chinese radios, and talk all you want on your own private channel.

[LittleJack]

First off, WOW! This is exactly the information I was looking for, and all in one comprehensive post. Bravo!!!

You mention that most of the internal radio communication used is encrypted. I'm assuming you mean departments like Gate, Rangers, FAST, etc. While I would NEVER want to interfere with any of those, I think it would be fascinating to know what's going on (such as gate closures). Is there any kind of listen-only scanner that would let me be an aural voyeur?

[Token]

Yes BMIR radio.

Bring an FM radio and listen.

[LittleJack]

I wish BMIR was actually Burning Man *Information* Radio, instead of hours of music, much of which is not to my taste, interspersed with seconds of information.

I have often wished that there was one BMIR for music, interviews, etc. and a second frequency for PSA's, theme camp event announcements, gate and infrastructure announcements, etc.

[Plugh]

I have often wished that there was one BMIR for music, interviews, etc. and a second frequency for PSA's, theme camp event announcements, gate and infrastructure announcements, etc.

Burn your radio. Or sign up for a BMIR shift and play what you like, or just do PSAs and interviews during your shift.

[Token]

Fair enough, bring a general purpose scanner and see what you can find out there.

[Skuzzy61]

Thanks to your post, I have ordered 2 of the UV82 radios.

Cannot thank you enough.

happy to be of assistance and glad it was enough to spur you purchasing the UV82's.

I'm debating having programming sessions on-playa during the event should anyone be having trouble with their new toys. If I think I can make it happen I'll post here about it and provide a couple of timeslots those with new radios or needing help can come by.

I got mine and programmed them to the frequencies you listed. Even without the computer software it was not bad to do. The radios seem well made. They have some weight to them. I LIKE EM! lol!