Very small tracker

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

rockets

Well-Known Member
Joined
Nov 18, 2014
Messages
1,274
Reaction score
56
Location
Denver, CO
can you make a small tracker that could fit an 18mm tube for really cheap? or buy one? I really need help! Thanks! :)
 
can you make a small tracker that could fit an 18mm tube for really cheap? or buy one? I really need help! Thanks! :)

The correct answer to your question is no. The smallest radio frequency tracker I'm aware of is the Walston:

https://www.walstonretrieval.com/sub-3.htm

At $159 it ain't cheap. When you add in the $450 receiver and a yagi antenna, your rocket better be worth a couple thousand dollars to make it worth this stuff.

I use the CSI tracker system:
https://www.com-spec.com/rocket/index.html

The tracker transmitter is larger, you need at least a 29mm tube to fit it into, but it only costs $100. The receiver is cheaper than the Walston by about $100 and comes with a built in antenna.

Since you can't really soak a lot of money into an 18mm rocket, it just doesn't make sense to put a tracker in it.
 
I believe bird trackers are on frequencies reserved for wildlife research and are not supposed to be used for other tracking.

M
 
can you make a small tracker that could fit an 18mm tube for really cheap? or buy one? I really need help! Thanks! :)

is $18.50 cheap enough?
https://distance-rc.com/store/beaconv2
I have one of these and it is exactly 18mm wide. fits snug into an 18mm tube. It runs on a single cell lipo and you can easily get one that fits in the tube. the downside is it does not transmit your ham call sign so it isn't 100% legal to use on ham frequencies. I have done some testing with a home made yagi antenna and a $30 baofeng ham radio with great results. I have not had an opportunity to test long range but it should be good based on the power output.
 
Last edited:
I believe bird trackers are on frequencies reserved for wildlife research and are not supposed to be used for other tracking.

M

I'm not sure that's true any longer, if it ever was. The Walston https://www.walstonretrieval.com/main.htm started out as a falcon tracker, but is now being sold as an airplane/rocket tracker. The frequencies haven't changed.
 
The Merlin systems are specifically available for rockets as well. They're about $100 for the transmitters but the receiver is $300+
 
First you have to look at what you're going to be using it for. If you want to put it into an 18mm rocket, chances are pretty good that you're not going real high, but you might want to be able to find it in some grass (or trees). One of the sonic trackers (like the one that Apogee sells) would be a good choice, but you have to get close enough to the rocket to hear it, of course. If you have a good general idea of "which way it went" then that would work.

If you're looking at radio tracking, you have to consider the cost of the transmitter and the receiver. Most of the lower cost systems are "beacon" transmitters that generally require a Ham radio license and some kind of directional receiver to use. If you're starting from scratch, $400 or more is a good budgetary number. Easier but generally more expensive are the GPS trackers, but I don't know if any of the ones currently on the market will fit in an 18mm tube. I was working on one, but I decided that too many compromises would have to be made to make it fit, mainly in terms of your battery options.

[Full disclosure: I design, make, and sell the Eggfinder GPS tracking system. It will fit in a 24mm tube.]
 
Easier but generally more expensive are the GPS trackers, but I don't know if any of the ones currently on the market will fit in an 18mm tube. I was working on one, but I decided that too many compromises would have to be made to make it fit, mainly in terms of your battery options.

I know Robert DeHate made a GPS tracker for a 13mm two stage carbon fiber rocket. The rocket is small enough that he want to be able to find it, the casings (13mm snap ring B motor) and the electronics for DD.
 
Just because a company sells it doesn't mean it's "legal". Comspec used to sell it's transmitters without a license, but the FCC put a stop to that. I suspect that the wildlife trackers are overlooked since they have such a low output power (and therefore require a very sensitive, and expensive receiver).

Here's a picture of a 70cm 16mw transmitter that I made for another customer, it's about 13mm wide. Even thought it's frequency agile, it's difficult to program due to its small size. That's the main reason I haven't made these generally available. Aside from being smaller and lacking a programming header, it has the same functionality as the larger 16mw transmitter that I sell.

https://www.bigredbee.com/images/small70cm.jpg

At any rate, if you're interested, contact me via email.
 
Last edited:
I know Robert DeHate made a GPS tracker for a 13mm two stage carbon fiber rocket. The rocket is small enough that he want to be able to find it, the casings (13mm snap ring B motor) and the electronics for DD.

This is the project I thought of when I read the thread title... crazy little rocket he has, there!


Later!

--Coop
 
I saw Robert's tiny GPS board at LDRS 29 I think. It was amazingly small, and consisted of several circuit boards daisy chained together with some flexible connectors.

Just for fun, I was playing with the PCB layout to see how narrow I could make my GPS board. I threw out the data logging memory chip, and all of those large, pesky connectors and got it down to just 15x45mm.

one could go even narrower with a small GPS like the Nano Spider from OriginGPS, it's just 4.1 x 4.1 mm !!!

Greg
 
I saw Robert's tiny GPS board at LDRS 29 I think. It was amazingly small, and consisted of several circuit boards daisy chained together with some flexible connectors.

Just for fun, I was playing with the PCB layout to see how narrow I could make my GPS board. I threw out the data logging memory chip, and all of those large, pesky connectors and got it down to just 15x45mm.

one could go even narrower with a small GPS like the Nano Spider from OriginGPS, it's just 4.1 x 4.1 mm !!!

Greg

Roberts is now one board. I didn't know him back then so I didn't know what it looked like, but snagged this pic last year (best I have): ImageUploadedByRocketry Forum1446160442.686843.jpg
 
I have a 70cm Marshall tracker that fits inside an 18mm body tube. Pricey but awesome stuff.
 
Hi JD,
I am confused!
Merlin's listing for Rocketry frequencies includes 3 band ranges the middle band range is 216mHz to 222mHz,
plus they have an option for custom frequencies.
I wondering if the Merlin System can read the short 5ms CW pulse signal that CSI uses.
 
The receiver I purchased covered 216 through 220.
They can do custom but, I didn't ask about it.

JD
 
Hi JD,
I was asking about Merlin transmitters working with a CSI receiver that covers the Merlin Transmitter Frequencies of 222mHz, As per their web site!
Ken
 
you could always build one pretty cheap (which is what I'm doing). an ardunino nano is 18mm (costs about £3 here) and you can get transmitters and receivers off ebay for £1-2 which use the ISM band (Industry Science Medical). Then you just have to connect them up with a few jumper wires and install some code (pretty easy to find stuff already written by others if that's not your thing). You can also go down the xbee route and use premade ones assembled by others but you'll pay a bit more for it (https://www.digitalsmarties.net/products/jeenode-micro). Have a read of this for some ideas :) https://www.instructables.com/id/Radio-Telemetry-for-a-Model-Rocket/
 
is $18.50 cheap enough?
https://distance-rc.com/store/beaconv2
I have one of these and it is exactly 18mm wide. fits snug into an 18mm tube. It runs on a single cell lipo and you can easily get one that fits in the tube. the downside is it does not transmit your ham call sign so it isn't 100% legal to use on ham frequencies. I have done some testing with a home made yagi antenna and a $30 baofeng ham radio with great results. I have not had an opportunity to test long range but it should be good based on the power output.

Ahhhhhh, Just use the Handi-Talkie to announce your callsign and intent on the frequency. Be careful about Baofengs in that the power meter is all on if any signal is detected and off if no signal is heard. Go here to check: https://www.miklor.com/
You really can't track with a Yagi unless you do it by ear as the meter is useless.

I was going to get one and experiment as the price is right. Listed as out of stock though. Kurt Savegnago KC9LDH
 
Ahhhhhh, Just use the Handi-Talkie to announce your callsign and intent on the frequency. Be careful about Baofengs in that the power meter is all on if any signal is detected and off if no signal is heard. Go here to check: https://www.miklor.com/
You really can't track with a Yagi unless you do it by ear as the meter is useless.

I was going to get one and experiment as the price is right. Listed as out of stock though. Kurt Savegnago KC9LDH

Thats exactly what i did when using it. I actually carried another ht to say my call every 10 minutes. This tracker is really neat. It transmits three tones on three power levels, you can set the level for each. I use a yagi and attenuator and no real power meter is required. The whole setup was under $100
 
Thats exactly what i did when using it. I actually carried another ht to say my call every 10 minutes. This tracker is really neat. It transmits three tones on three power levels, you can set the level for each. I use a yagi and attenuator and no real power meter is required. The whole setup was under $100

Oh yeah, I transiently forgot. If one has an attenuator/yagi connected, can't transmit through the attenuator without messing it up. Kurt
 
Oh yeah, I transiently forgot. If one has an attenuator/yagi connected, can't transmit through the attenuator without messing it up. Kurt

You should always have more handi-talkies than hands.
 
Back
Top