FMKit [Lost model locator]

[discv]

This bit of radio beacon kit has taken my interest. Could any kind soul/s shed some light, that I can understand.
The posts on RCgroup are way above my head :?

So far as I can understand- this tiny transmitter [around 50 USD] is paired to a compatible hand held radio.

Under a given parameter [lack of sound?] the transmitter activates, and sends a series of signals that will permit the radio to be used to locate the lost model. I believe the range to be up to 6 Km.

If my basic understanding here is correct, my first question is how does one go about selecting a 'compatible radio' - and what is the information with regard to channel/frequency that has to be given to the developer when ordering.

If anyone could put together 'a complete muppet guide'- I would be most grateful.

This is the link to the developer- http://fmtv.us/rf_beacon.html

 

[DeweyAXD]

Clever bit of kit for what it does (I'd never heard of it before). This video explains a little: http://www.youtube.com/watch?v=Jsv3lyGONjs

It looks like you simply buy a either an expensive programmable radio/scanner (where you can tell it the exact frequency to be on) or just a cheap 2 way PMR radio (that uses the pre-set frequencies at the bottom of the developer page). You then decide which channel you want the FMKit to transmit it's tone onto. That is programmed into the board by a series of button pushes.

Once programmed it seems you can set it to either always transmit or you can tell it to use the built in microphone to detect when there is no noise (like when the props stop because it is hanging from a tree :lol: ). It then transmits a set of tones which your radio will pick up. All you need do is set the radio to the channel you programmed it to.

You then roam the world in the general direction your craft vanished with your radio on, hoping it will change to a new tone (suggesting you are closer), you then look around that area and hope for the next tone etc etc.
Great for wide open spaces in areas you can actually roam around but no good in built up places where access to search is limited/illegal because if you can't get close enough you will never get the stronger tones.

Nice concept as a back up maybe (especially as its light) but if you don't have a 2way set already its not 'that' cheap an option. PMR radios have a lot of traffic/interference on them and even the '12km' models are only good for maybe 500m without line of site! It is better suited to a good programmable radio if you want range but then the cost goes way up.

If you are not technically minded and afford an extra 75g weight you are better off with a Garmin GTU10 IMO - that will show you where it landed within a 3 metre radius on a map, USB charges, last 7 days and works right out of the box.

 

[discv]

Many thanks for the info, Dewey. Nice concise answer.

Given that any other type of locator will cost [min] £200 per year, and that cost ongoing- would trying to source a PMR scanner covering the frequencies shown on the developers site be worth even thinking about.

Nurse- he's got out of bed again :evil:

 

[DeweyAXD]

Many thanks for the info, Dewey. Nice concise answer.

Given that any other type of locator will cost [min] £200 per year, and that cost ongoing- would trying to source a PMR scanner covering the frequencies shown on the developers site be worth even thinking about.

Nurse- he's got out of bed again :evil:

No probs. I think trackers are a hard choice to make. Personally i found it painful to pay anything for something I really hoped to never use but after a couple of 'holy crap I've lost site of it' moments in my first few flights when i was a newbie it made me feel a lot better.

Your comment of £200+ a year???.... what ones have you been looking at? GTU10 is Free for the first year and £45 per year after that.

I see you are UK based. If you wanted to go the FMKit route then just head to Maplin and get something like this: http://www.maplin.co.uk/twin-pack-latit ... ios-218002
(Argos do them too but they are £35). This will only give you 3km range with clear line of site (so probably 300-400meters at best without it). If you need more range these work well for voice over a mile or so (I have a set):
http://www.argos.co.uk/static/Product/p ... 531103.htm

These are both PMR radios and hence are on the same bands as the one in the video (8 channels on the 446 band).

If you fly over open fields with easy access then this 'could' work for you but I'd still urge you to spend the extra on GPS. A tracker is only worth spending money on if you can be at aleast 90% sure of finding it when lost. Otherwise you loose the investment you made on it AND a Phantom/Camera.

 

[discv]

Thanks again Dewey.
Given that I am a newbie, and fly in open spaces only, the hazards are long grass and trees.
I like the very light weight of this device.
And I loathe ongoing subscriptions.

Forgive me for hanging in with the research, but how about this for example;
http://www.ebay.co.uk/itm/NEW-Uniden-Be ... 9397624%26

 

[DeweyAXD]

No probs. Yeah that should work. Not sure on what sort of range it will have but probably be pretty good.

Keep us all postage how it goes if you go that route.

 

[discv]

Trying to research this RFKit is getting interesting.

The developer is considered to be a Russian/Israeli genius. There is no web site- and NO you can't have a manual !

He will sometimes take a question on the RCgroup- if you are very lucky.

Here is his answer to my question asking that the difference between Vox & non Vox be explained:

there is only one version of beacon (VOX), it combines features of older (year ago) different versions. When completing order you offered to set specific channel, if asked I just click in 6 numbers before sealing the envelope, you can set custom channel (3.1) yourself anytime.
Lack of noise activates the beacon(2.1 + 1.10)
in VOX mode(2.2) the transmitter triggered by noise and works as spy bug, as shipped you'll hear unmodulated carrier, to hear voice add 1n capacitor in series w/ 2k resistor between 3rd pad (IRQ) of RFM42b module to nearest crystal pin.
few times I was asked to block spy option to make the beacon legal to use and import , now shipping all beacons with working VOX but transmitting unmodulated carrier unless two parts added.[Unquote]

Aah, now I understand :?

 

[DeweyAXD]

Interesting. So it sounds like it may have started its life as a hidden microphone bugging device that transmits when it hears noise but then moved onto it being a locator as well. What he is saying there is that when you buy it you can ask him to pre-program a channel to it (saving you the hassle). To explain.... You buy the programmable radio and you choose a channel on it e.g 462.22 - he programs it to work on that channel before shipping.
He then is saying you have the option of doing that yourself anyway.
The VOX thing is the bugging device function. He has obviously got stick for shipping illegla voice activated bugging devices abroad so he has deactivated the function by removing 2 parts that, if fitted (a capacitor and a resistor), turn it back into being able to be a bugging device.
Basically I'd imagine this ex military tech (from like 10 years ago) earning a few quid on the RC market :lol:

 

[discv]

Yes Dewey, I think this thing has a sinister background!

Could you expand on this line of yours:
You buy the programmable radio and you choose a channel on it e.g 462.22

Is a programmable radio different from a 'walkie talkie'. And what would I be considering when 'choosing' a channel

The guys on RCgroup reckon to skip my idea of a scanner- and go for a Baofeng radio

 

[DeweyAXD]

Ahhh the old Baeofong! lol - yes very popular (if not entirely illegal in the UK without a license i should add ).

Ok - So before I get into that.....walky talkies in the uk use PMR - these are 8 pre-defined channels these are: 446.006, 446.019, 446.031, 446.044, 446.056, 446.069, 446.081, 446.094. On an Argos walky talky you won't see these numbers shown, you will just see channel 1-8. When you use one channel to talk and suddenly you hear some stranger talking you switch to a channel with (hopefully) less traffic. In your case you just want to hear that tracking tone clearly.

Lets say you take a wander down to Dover docks... here you will find that there is interference (As in other voices talking and noise) on nearly all your channels as it is a busy area and people will be using them for business around the docks.

So a programmable radio allows you to listen on a frequency outside this range standard 8 channel range. You would first your radio to a channel like say 446.011 and listen for noise and interference. If it is noisey you pick one until it is clear. You then buy the FMkit and program it to this channel (or get the developer to set your radio to the same before you buy). This way you are not on a frequency used by every PMR radio in the country and hence 'should' be able to get a nice clear tracking signal.
Two downsides - 1) You could get out to the field, lose the device and only then discover your chosen frequency is full of noise/talking 2) you may well be using a frequency that needs a license.

The Baefong is populare as it works as a transmitter as well as a reciever... the example you showed before was just a reciever as far as i could tell. The baeofong is capable of being used over long range as a 2 way but on channels that are, frankly, restricted for use by non licensed civillians.
You can't use it for emergancy bands as they are encypted now but I think you could use it to transmit on civial aviation bands (yes as in talk to planes!). The most popular use for them is to use them as CB radios (as in the ones truckers use). This is illegal without license as you have to have a registered call sign that is used on all transmissions to identify yourself "10-4 rubber ducky" etc. Licenses are cheap (like £20 a year) for this but it won't allow you to use that band for tracking your lost craft.

Ok so now you may be more confused than ever I am sure... this is why I am still suggesting going the safe route. Pick the wrong channel and you end up transmitting a loud signal on a channel you are not allowed to (which they can of course track)... that could land you in trouble. To make it work well for you I would suggest you get good at programming a frequency into the FMkit at the field. That way you can find a clean channel for that day and then be sure that, if it goes down, you can find it.

Hope that helps.

 

[discv]

Dewey, brilliant write up- though I don't understand it yet- but I will !

Been gone and ordered a Baofeng UV-5R2. 5 watt/ £30- and even if my plan goes belly up- I can listen to LBC 97.3 on it
I will order an RFKit AFTER I have played with the radio, and IF I reckon I might be in with a chance.

So---this weekend you will be taking off from a metal barge- and over water :shock:

So---- you may have time spare to peruse this radio and give me your thoughts- but I sincerely hope not!

Again, many thanks

 

[The Editor]

Guys,

I've been looking through this thread but fail to see how this system could be reasonably used to locate a 'lost model' without a very narrow beam yagi (or similar) and a great deal of skill !

You would only have the signal strength meter on any rx you purchased to give you an indication that you were 'getting' closer.

Without the proper equipment and knowledge you would only be aware of a 'beacon' being transmitted on a set frequency somewhere within it's transmitting radius.
Assuming you are at the center of the circle (home point) when you model is lost you will only have line of sight where it was last seen to start walking towards (this would not take into accounts wind, Naza funny business where it might have flown off at 90 degree after you last saw it etc).

I maybe missing something here but I do NOT see this as any solution to locating a lost Phantom!

 

[DeweyAXD]

Guys,

I've been looking through this thread but fail to see how this system could be reasonably used to locate a 'lost model' without a very narrow beam yagi (or similar) and a great deal of skill !

You would only have the signal strength meter on any rx you purchased to give you an indication that you were 'getting' closer.

Without the proper equipment and knowledge you would only be aware of a 'beacon' being transmitted on a set frequency somewhere within it's transmitting radius.
Assuming you are at the center of the circle (home point) when you model is lost you will only have line of sight where it was last seen to start walking towards (this would not take into accounts wind, Naza funny business where it might have flown off at 90 degree after you last saw it etc).

I maybe missing something here but I do NOT see this as any solution to locating a lost Phantom!

Well I have to agree Editor.. personally as I've said I think it is a risky project and not one that should be relied on. The concept of the device as far as I can tell is to not rely on the signal strength indicator of the radio set itself, instead the device emits a tone which changes depending on its own strength. The use of a radio is purely to be able to hear that tone and the frequency used is key to how clear that signal is. How that actually works is beyond me technically (I'm going from the youtube vid). Seems to work right next to the device but what happens at range audioably I'm not sure.

I fear there could be a whole lot of walking around frustrated in the event of loss but I guess it 'might' lead to a find and is better than nothing at all.

It has advantages over something like the Tile in regards to a longer range with a good signal but unlike the Tile (or other bluetooth trackers) it won't tell you exactly where it is when you get within 100ft.

For me it is a flawed method of tracking and looks more like an ex-military guy finding a use for something he likely designed in the commercial world..... but hey it is a project and fair play to the OP for taking it on I say. I for one will look forward to hearing about how it goes.... I just hope the later posts don't come with a 'Lost Phantom - FMkit useless' title

 

[discv]

Editor, your observations are valued- but not what I want to hear

I do not know the answers, but I intend to find out. The radio I have bought at a good price- and can resell on Ebay- if it all fails.
So now I'm into risking another £35 on the RFKit.

So on the plus side- I have already learnt a lot, and will learn a lot more.
The worst case is I'm £35 out of pocket.

Now a lot of guys on the RCgroup 'claim' success with this kit- surely they are not ALL dreamers.This I will let you know :roll:

My latest thought-- is if I can set this kit up to transmit on an illegal channel when/if lost, and if my ID is on the phantom, the authorities will track and find my lost model for me- and bring it to my door. Clever ehh.

 

[GearLoose]

Interesting discussion... as it happens, I have the FMKit beacon and recently bought the older Baofeng UV-100 radio to locate the beacon. Previously I'd used a Motorola Talkabout 4600 radio but it doesn't have a removeable antenna or squelch, so I was having problems using it to locate the beacon.

Although I have no doubt that the FMKit can be used to locate my Phantom, focusing the search continues to be a challenge. You do this by intentionally blocking/attenuating the signal received from the beacon by your radio. Peter, the developer, told me to use my body and to spin in a circle with the radio held against my chest. Unfortunately I have a balance problem and can't do that without falling over

Other methods include wrapping the radio in aluminum foil, removing the antenna, adjusting squelch, and even putting the radio inside a tin can.

By the way... if you remove your radio's antenna DO NOT TRANSMIT or you'll fry it, just as I fried my FPV tx by forgetting to connect the antenna.

So... I was about 800 feet from the beacon in heavy forest and got a weak single tone signal, repeating every several seconds on my radio (I use channel 5). As I move closer to the beacon, I begin to get two tones... then three. To focus the search I need to identify the direction which gives the strongest, clearest tones and move toward the beacon.

It obviously takes practice.

Advantages -- I live far away from cell phone service and seldom fly in open areas, so this is my only realistic hope of finding a "Phantom in a haystack". Also, the beacon and its tiny battery are ridiculously small. I put it in a small pill bottle and fix it to the Phantom's landing gear with Scotch tape.

If I know that I will be flying where there's cell service, I'll be using the FiLiFi GPS locator with an AT&T sim card. Cheaper annual cost than the Garmin and similar GPS units.

 

[DeweyAXD]

Interesting Gearloose - you highlight a situation where it certainly would be good as a back up solution (albeit a very long winded dizzing one!). You can get Attenuators on ebay like this that might work: http://www.ebay.co.uk/itm/Microwave-Att ... 3f22613f07 depend on the antenna type i guess.
I guess one of these plus a Tile or other bluetooth device would be a good combo... draws you close enough to get withing Bluetooth range and then use the app to locate it (although that depends on how the app map works... offline would be ok, online a no go).

Discv - sounds like you will need to practice with it quite a bit on the ground before relying on it. Would be good to get some youtube vids up of these trials as I am sure people living way out in the sticks would appreciate seeing them.
I like your idea of using an illegal band to help find it ... flawless until they find your phantom (drone) with some ex-israelly military developed bugging/homing device on it and you end up in a dark room at Mi5 - best put some KY jelly in the Phantom kit :lol:

Seriously though have fun with it... as you say its a learning curve and that is what hobbies are all about.

 

[discv]

GearLoose, I was hoping you would jump in on this- I had noted previously that you were playing with this kit.

I have not had a chance to read your post in depth, but anything more you can throw in the mix- please do.

 

[discv]

I like your idea of using an illegal band to help find it ... flawless until they find your phantom (drone) with some ex-israelly military developed bugging/homing device on it and you end up in a dark room at Mi5 - best put some KY jelly in the Phantom kit :lol:


Oh I hadn't thought about that :!:

 

[Driffill]

Ex military???
Israeli genius??
Russian spy???
Peter???

Lmao, really wanna know who developed this technology???

http://research.microsoft.com/en-us/um/ ... raints.pdf

And I'm sure a search on alibaba or similar will yield hundreds of results for items like this. Being that they use frequencies that we shouldn't be transmitting on, they cannot be legally sold on shelf and there fore we don't see them, like radar detectors. Some place they are common, in Australia they are a black market item!

 

[BruceTS]

Another way of narrowing down the search area is by triangulation, once you get a signal, try and pinpoint the best direction. then travel off to another location and do the same, the intersecting lines will get you in a more general location to start the hunt. That's how I used to do it, unless you already know it's nearby.

Hopefully the Tile works as intended, this could help locate it even quicker.