Telemini ground station req?

I’ve used TeleGPS with a Teledongle, Arrow 440-5, laptop, and a UV-5R to track two comp rockets. Can someone explain their basic setup with a Telemini to RDF radio track it? Assuming it feeds into Teledongle but only gives heading or distance.

I don’t have a Telemini yet but want to acquire one. I would like to know what kind of ground station it requires.

Ooops.

I just want a heading and maybe if possible distance to it via its telemetry data radio style. Like in a plane they call it distance measuring equipment and ADF for automatic direction finder where we know which direction a radio station is from us on a radio link. I understand the RDF does not do all a gps does.

The UV-5R was garbage. I’d use it to call out that I was in a frequency band. It would not receive distance or headings via RDF.

What are its “integrated telemetry” capabilities? It claims to be a transciever and I hope it’s a simple radio beacon on ham band in addition to being an altimeter. What I want is at least a vector to it.

W7AMI said:

The Telemini is not a tracking device. It reports back the altitude but not the location since it doesn't have a GPS receiver. The TeleGPS, Telemega and Telemega do have a GPS receiver and are able to report the GPS position. Your antenna, laptop and Teledongle are all you need for the ground station. You can use the UV5R to track the TeleMetrum products but since I don't have a UV5R I can't give specifics. I'm sure someone with experience will be along shortly.

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Here says it has basic radio beacon.

https://www.rocketryforum.com/threads/ad-altus-metrum-releases-telemini-v3-and-altos-1-7.140294/

I want to harness this radio beacon feature.

The telemetry downlink of the TeleMini doubles as an RDF beacon and the telemetry transmission can be used to RDF the device without specifically using the telemetry feature. To leverage telemetry via a TeleMini you need either a TeleDongle or TeleBT to receive the telemetry strings and a ground station to record the values.

Obviously the TeleMini isn't a GPS tracker so you don't get GPS positioning values but you'll get max height, max speed, max boost acceleration, average boost acceleration, drogue and main descent rate, ascent, decent, and flight times all reported in real time over the telemetry link. Just be aware that the values might not be completely accurate. My flight in June listed my max speed over the telemetry at Mach 2.6 but when I downloaded the full flight log and queried the resulting eeprom flight file my actual value was Mach 1.8.

To RDF a TeleMini tune your handheld to the frequency the TeleMini transmits on and track it like you would any other non-GPS capable transmitter.

What handhelds are you guys running??? I think this is where I screw up as a new guy???

Yaesu VX-8GR. Realistically it's overkill for simple RDF use but I have it for its APRS capabilities. Your Baofeng should work fine for RDF use. You should already have experience with using it to RDF as your OP states you've used it to track comp rockets twice? The process is identical.

Used Teledongle on the laptop for gps. No RDF track except in a Cessna 152 lol. We weren’t RDF capable on the Uv-5r.

Would a VX-6R work to radio beacon? What’s the cheapest I can go that still radio beacons? Otherwise I’m looking at the T-72 kenwood. I’m new at this.

I'm not sure I follow you. If you had a telemetry downlink from the TeleGPS it was obviously transmitting RF. You can RDF that RF transmission regardless.

The UV-5R heard beeps. It wouldn’t direction find it by itself. It was a comms talking handheld. Not a direction finder capability. We punched coordinates from laptop Teledongle to an iPhone for gps work.

Completely ignorant here... I just got my ham license a year ago and used it twice lol.

Andrew_ASC said:

Would a VX-6R work to radio beacon? What’s the cheapest I can go that still radio beacons? Otherwise I’m looking at the T-72 kenwood. I’m new at this.

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Yes, as it's able to listen on the frequency the TeleMini transmits over so coupled with a yagi it can be used to RDF a TeleMini.

The Kenwood TH-D72 is a GPS equipped APRS TNC which is completely useless for simple RDF tracking. It's also quite long in tooth imo. If you're looking to decode APRS in a handheld I'd recommend you look at the newer Yaesu's, specifically the FT2DR.

https://www.yaesu.com/indexVS.cfm?c...11&encProdID=4A66D869E574453F343581B53E9FAB40

Just be aware that the GPS and APRS TNC capabilities of the radio are completely useless when used in conjunction with a TeleMini.

Thanks dude. All that handheld spec was gibberish to a new guy like me. But you make it easier to understand what handheld to use with what tracker or gps.

Andrew_ASC said:

The UV-5R heard beeps. It wouldn’t direction find it by itself. It was a comms talking handheld. Not a direction finder capability. We punched coordinates from laptop Teledongle to an iPhone for gps work.

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Does it have a signal strength meter? Have you ever RDFed anything? You use the beeps you hear over the handheld combined with the signal strength meter to guide you to the rocket. If it doesn't have a signal strength meter you should find something that does.

It didn’t have a strength meter. We would hear beeps until signal lost by obstacles.. Even using gps to find it. The beeps never changed volume or pitch as we got closer. That’s when I realized the Uv-5R wasn’t going to cut it.

With reference to the VX-6R, yes, that would work perfectly. Have a look at the brochure from the Yaesu web site below.

https://www.yaesu.com/downloadFile...._Brochure.pdf&FileContentType=application/pdf

You'll notice in the photos below the frequency value is the signal strength meter. That's what you use to RDF a rocket. Combined with a yagi that meter will allow you to "find" a bearing to get you closer to the rocket. Point the Yagi in various directions, whichever gives you the best signal is the direction you should go.

Andrew_ASC said:

It didn’t have a strength meter. We would hear beeps until signal lost by obstacles.. Even using gps to find it. The beeps never changed volume or pitch as we got closer. That’s when I realized the Uv-5R wasn’t going to cut it.

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That makes more sense. I've never played with the Baofeng hardware so I'm not across the hardware capabilities.

It was a budget model like $30.

Andrew_ASC said:

It was a budget model like $30.

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Yea, I've seen the 2 pack ebay deals before, I've just never had the inclination to buy one as I don't have a clear use case for the hardware.

I have the FT2DR, and really like it. I get the GPS data from my teleGPS no problem, and I have used it for RDF location of a rocket with a BRB 70cm tracker and Yagi.

Also, piece of mind when hiking with the kids where cell phones don't work. Accurate GPS coordinates, and a way to call for help. A really useful (and small/lightweight) tool all around.

Who makes FT2DR?

I’d like to not spend like $500 just to track a 24mm MD. But welcome to rocketry I guess. Hahaha.

Whatever radio you're using for DF needs to have a good signal strength meter. That has to be coupled to a directional antennal. I tried a Baofeng UV-5X3 and even though it has a simple signal strength meter, it was pretty much useless for DF with a Yagi. I was, however, able to find my rocket my using my body as a radio shield and walking towards the null.

To do that, you're putting a giant bag of water (your body) in between the radio and the Telemini. Turn the squelch off, then turn 30-45deg at a time to listen to the Telemini's beep. If you're holding the radio flush with your chest, keep turning until you don't hear the Telemini. You're then facing away from the Telemini...turn around and walk that way. If you get close enough that you always hear a signal, you can remove the antenna and keep doing it (just don't hit the transmit button without an antenna).

You already have a Teledongle though, right? That reports signal strength. You should be able to hook a directional antenna up to it, then slowly point the antenna in different directions, then walk towards the peak. If you have an Android device, you can hook up your Teledongle to it and use the AltosDroid app to see the signal strength (RSSI).

You wont' get a direction or distance from your computer screen though. There are lots of videos on YouTube and websites about ham fox hunting. There are lots of ideas out there.

One gotcha I've seen is you may get radio reflections off of nearby mountains, fences or other RF reflective things. Don't get spoofed by that.

...also, practice before you fly.

Andrew_ASC said:

It didn’t have a strength meter. We would hear beeps until signal lost by obstacles.. Even using gps to find it. The beeps never changed volume or pitch as we got closer. That’s when I realized the Uv-5R wasn’t going to cut it.

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Without a (working) signal meter, you can use a directional antenna ( like a yagi) and an external attenuator. This will attenuate the beeps and help you determine direction. Search for UHF Fox Hunting on your favorite search engine for ideas and methods. There are many ways to do it.

Without having (GPS) coordinates at both ends, you can't calculate a bearing or distance, so it's impossible for the TeleMini to transmit either. The Baofeng can't decode data packets anyway, so you would need a separate decoder attached to your receiver.

Andrew_ASC said:

Who makes FT2DR?

I’d like to not spend like $500 just to track a 24mm MD. But welcome to rocketry I guess. Hahaha.

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Yaesu. I put the link to the handheld in a previous post less than an hour ago, look above.

As I mentioned in the same post the radio's GPS and APRS capabilities aren't required for your use, so it's overkill. BUT, if you plan to buy a Altus Metrum or BRB GPS device having an APRS TNC capable device is useful, especially with BRB as that's the only way you'll be able to decode the APRS transmissions from the tracker.

The Kenwood TH-D72's aren't cheap either...

None of it is cheap: I respect that. These are all quality units. Specialized hardware.

I need to grab another Teledongle and a yagi again because I’ve donated mine to a university team. I can finish the 24mm MD airframe easy for now.

Trying to graduate with engineer degree mechanical this fall too. Didn’t do well trying this summer: needed a vacation.