Unfortunately, walkie-talkies are banned at events. (If I had looked this up before spending my morning looking at walkie-talkies I would be less annoyed. My fault). The community consensus seems to be that this is because field staff, refs, et cetera want to be able to use the channels unimpeded. Fair enough.
(If you suspect that walkie-talkies are banned for other reasons please explain; I imagine it would be relevant).
Either way. I am looking for a (legal) alternative to walkie-talkies (not cell phones, see below) mainly for communicating with our field rep during alliance selection. This wonât be used to communicate with the drive team during the match so forget about H303. Other potentially relevant rules are E301 (tldr; no 2.4 or 5 GHz).
What I Want
Two way communication. Generally the strategy team in the stands makes the call and that flows to the field, but for second picks often we need to communicate with our field rep and the field rep of our first pick/alliance captain.
Media text at a minimum but voice is a lot more convenient.
Reliability. Iâm already aging fast enough. I donât need more stress.
Absolute minimum range: 100m line-of-sight. I figure this should be enough for champs but a lot more range and not requiring line-of-sight would be nice. Bonus points if these devices can be used to communicate with anyone in a champs-sized venue. I was looking forward to using walkie-talkies (rip) because they ostensibly have quite good range and should be able to work through a good amount of concrete.
Portability. It would be best if the device could be worn on the belt. If necessary, I suppose we could have our field rep carry it out in a backpack. Either way, we would likely want an ear piece and lapel/boom mic for the convenience of the field rep.
Form factor. If it looks like a walkie-talkies and works like a walkie-talkie I am probably going to have a hard time convincing event staff that itâs within the rules. Might be best if the user interface portion of resembled something common place like a phone.
Number of notes: at least two. It would certainly be nice if we could also have one device stationed in the pit for easy pit-stand communications.
Cost < 100 USD/device. I would be willing to consider more if the solution is ideal and doesnât require much work on my part.
Why I Want It
Anyone have any ideas?
Wifi at events is not a guarantee (though Eduroam at the Ontario district events is pretty good).
Cell service is also not guaranteed, particularly not in giant concrete boxes like stadiums. At Ontario champs this year our field rep didnât get service on the field (needless to say this caused a great deal of unnecessary stress).
Some day we would like to go back to worlds (please bring back a northern championship) and reliable roaming service is even rarer. For IRI this year I purchased roaming data⊠only to find I couldnât get any service at the venue.
I went digging through Chief history and found this post
and this post with an unfortunately dead link:
My current line of thinking is a two-way radio, as mentioned in the above post, (no idea how big those typically are) in a form factor that is portable but doesnât resemble a walkie talkie. Unfortunately I have no idea where to find such a product or how to put one together. (Edit: handheld ham radios appear to be a thing you can buy but cost a fair bit of money).
I make no representation on how legal it will be in future, but for 2023 it passed muster.
By the way, I could be unknowingly getting this wrong but Iâm under the impression that ham radios need licensed operators, not that the licenses would be terribly difficult if you start now.
The Wikipedia definition of Walkie-talkie includes two way radios and doesnât specify a band:
A walkie-talkie, more formally known as a handheld transceiver (HT), is a hand-held, portable, two-way radio transceiver.
So I think something like a CB handheld radio would also be classified a walkie-talkie, despite it not being on the UHF FRS band.
I would assume one of the concerns (beyond interfering with event staff radios) is thereâs not enough unlicensed two-way radio channels to allow all teams to use these devices without interference. Just imagine if you found a good solution here but everyone at champs was trying to use it too⊠600 teams on ~30 channels is not going to go well. Cell phone networks have more advanced cooperative multiple access protocols to avoid this problem.
If you just want a PTT style device friendlier than a cellphone, this looks like a really cool device⊠but it uses 4G LTE (or wifi) for connectivity (and itâs unclear how expensive it is going to be). https://relaypro.com/
If we take âWalkie-Talkieâ to mean any portable transceiver thatâs a blanket ban on anything a student could take onto the field for alliance selection (which might be the point). It would be nice of they were more clear with their language though (i.e. say âportable transceiverâ instead of âwalkie-talkieâ). I might get a license in Canada and the US anyway though because it sounds cool and not too difficult.
Based on past Q&A responses, the intent here really is to avoid conflict with event operations. The radios the event uses have a few different bands that are dedicated for different purposes (refâs have their own, CSAâs have their own, etc) for the event volunteers who need them to use.
Itâs not the intent to ban any communication device students can bring on the field for alliance selection. Way too many teams utilize cell phones for that (without any issue beyond what are often annoying long wait times for them to get the pick sent to them). So long as your device isnât a walkie-talkie, then you should be fine with regards to that rule. It would be nice if FIRST specified specific radio frequencies you were not allowed to use, but there may be some variation depending on the specific radios used at each event (Iâm not sure if districts provide their own, and if they may be different from the ones FIRST provides at regionals).
Since weâre talking about wireless communication, itâs also worth mentioning the ban on setting up your own wifi networks as well (E301).
A few people have talked about using LoRa for transmitting scouting data wirelessly, which is a very similar concept. If you use the 915 MHz band you donât need a license (as far as I can tell), and there are plenty of chips available for transmitting and receiving on it.
I used the tech for a science research project and i used this chip: Moteino. Make sure you buy the correct version and you also need a USB to FTDI programmer.
Take a look at a cheap radio like a baofeng⊠Just make sure that you are on an acceptable frequency (FRS, etc) that doesnât require licensing, otherwise the FCC will get mad.
Of course they canâyouâre at their event. Youâre violating E109. Itâs no different than running a wifi hotspot (also an âopenâ frequency, also violates an event ruleâE301). Enforcement is in the Event Rules Manual:
Universal Violation Note: A violation of any Event Rule will result in a verbal warning. Egregious or subsequent violations will be addressed by the Head REFEREE, the Lead Robot Inspector (LRI) and/or Event Management. Teams should note that egregious and frequent violations may be shared with the Judge Advisor which could lead to disqualification from awards
I completely get where the OP is coming from but isnât it kind of crazy the lengths teams will go to ensure they have communication with their rep on the field? I understand there is tradition with one student rep on the field announcing the selection (there was also âtraditionâ with putting robots in a crate for weeks and forcing teams to build backup robots, playing luck of the draw with backups at the Championships and many other examples of rules making it unnecessarily harder for teams), but teams have progressed and improved their scouting where itâs really hard to make picks without have some contact with the rest of the scouting team. I really think itâs time FIRST looks into changes how alliance selection occurs. FIRST should be making it easier to collaborate not harder.
Which is in violation of the law - but I think we can all agree that weâd not like to have field faults so we agree to reduce wifi signals to reduce interference.
And âNone of the FRS channels are assigned for the exclusive use of any user. You must cooperate in the selection and use of the channels in order to make the most effective use of them and to reduce the possibility of interference.â from the FCC website. Which I take to mean to use a different channel if someone is already on that oneâŠ
Thereâs plenty of spectrum to go round for this use.
It would be sad to see the spectacle of alliance selection go away⊠but I imagine there should be some way to make a show of it while also not having one isolated student on the field. Iâm just not sure what that way would be.
Technically, E301 calls out 2.4GHz and 5GHz WiFi specifically, meaning the new WiFi 6E (6GHz) should be exempt from that rule, at least as itâs currently written.
The routers are still expensive, but it looks like you can get compatible laptop M-key cards for ~$30 on Amazon, and USB dongles for under $100. Maybe possible to run something ad-hoc that way? On paper they have a range of âup to 600 feetâ LOS, so, might be viable?
My interpretation of this is that by specifically calling out the 802.11 standards and the 2.4ghz/5ghz frequencies, they are de facto allowing other specs and frequencies that fall outside this range. The phrasing of âad hoc networksâ appears to just be an example of those standards in-use by my reading.
The FCC ruling says you cannot jam wifi hotspots (e.g. by attacking them wirelessly or creating intentional interference). It does not say that you canât eject people creating wifi hotspots from the premises or otherwise penalize them (e.g. disqualifying them from awards).
No, there isnât. There are only 22 FRS channels. At champs, between 8 fields, other venue/staff comms, etc, I bet the channel allocation is full. If it was allowed, youâd have 600 teams trying to also share the 22 channels. Even at a small event, there wouldnât be sufficient channels to have one per team even without counting the event needs.
In any case, the event rules are the rules. You can argue they donât make sense or should be changed, but you shouldnât be surprised when they are enforced at an event. This is no different than how violating a robot construction rule will result in you not being able to compete until the issue is corrected.
