TH-D72 and Telemini

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jondub

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Can anyone tell me how to set up the Kenwood Th-D72 to receive the directional signals from the Telemini?

No problem configuring, connecting or even firing igniters but can't figure out the real reason for using the device.

Jonathan DuBose
TRA 11505
NR 80588
L3
 
The Tele-mini is not an APRS tracker if I'm not mistaken. You have to tune into the frequency and listen to the beeps and use a Yagi with an attenuator to RDF track. Look carefully at the Altus instructions. There is a "default" frequency the Tele-mini is set on. I left my notes at home as I tested it out, it worked and set it aside to plan a project for it. The instructions talk about "resetting" it to a default frequency but it actually come already tuned to that frequency. I really had to dig to find the info
in the voluminous instructions. Kurt
 
Right, what we are looking for is how to get the Kenwood to pick up the "beeps". I think we have everything else figured out except for the Kenwood settings. The silly thing about this is that Keith Packard helped me recover a rocket up at the Brothers site a couple of years ago and we used this signal which all Altus Metrum put out. He was using his Yaesu though. Isn't this the same thing as using the old Walston signals or am I totally misunderstanding this?

Like someone says Altus Metrum instructions range from very good to non-existent or maybe they are making assumption about how sophisticated I am not on these things.

Jonathan (and my grandson Juniper Slouber who is the actual use here)
 
I believe that you need either a TeleDongle or TeleBT to program the TeleMini. You won't be able to program the TeleMini via your Kenwood.
From the manual...
TeleMini is configured solely via the radio link. Of course, that means you need to know the TeleMini radio configuration values or you won’t be able to communicate with it. For situations when you don’t have the radio configuration values, TeleMini v1.0 offers an emergency recovery mode. In this mode, TeleMini v1.0 is configured as follows:

  • Sets the radio frequency to 434.550MHz
  • Sets the radio calibration back to the factory value.
  • Sets the callsign to N0CALL
  • Does not go to pad mode after five seconds.

To get into emergency recovery mode, first find the row of four small holes opposite the switch wiring. Using a short piece of small gauge wire, connect the outer two holes together, then power TeleMini up. Once the red LED is lit, disconnect the wire and the board should signal that it’s in idle mode after the initial five second startup period.

If you don't know what frequency your TeleMini is set to you could turn it on and listen with the Kenwood on each of the 10 channels the TeleMini is likely set to. The frequency channels start at 434.550 MHz and go up in increments of 100 KHz to 435.450 Mhz. Or you could do the emergency reset procedure outlines above.
 
Tune the D72 to 434.550 and you ought to be able to hear it beeping. The TeleBT or Dongle is I guess needed to reprogram. I have a TeleBT and hope that will work for reprogramming. I think Terry is right. One needs on Tele dongle or a TeleBT to program.
I "think" the altitude may get transmitted if one uses a TeleDongle of TeleBT for "live" data monitoring but an H/T is all that's necessary along with the right "stuff" for tracking the signal for finding the rocket.

TeleMini is configured solely via the radio link. Of course, that means you need to know the TeleMini radio configuration values or you won’t be able to communicate with it. For situations when you don’t have the radio configuration values, TeleMini v1.0 offers an emergency recovery mode. In this mode, TeleMini v1.0 is configured as follows:

Sets the radio frequency to 434.550MHz
Sets the radio calibration back to the factory value.
Sets the callsign to N0CALL
Does not go to pad mode after five seconds.
To get into emergency recovery mode, first find the row of four small holes opposite the switch wiring. Using a short piece of small gauge wire, connect the outer two holes together, then power TeleMini up. Once the red LED is lit, disconnect the wire and the board should signal that it’s in idle mode after the initial five second startup period.

Any operation which can be performed with a flight computer can either be done with the device directly connected to the computer via the USB cable, or through the radio link. TeleMini doesn’t provide a USB connector and so it is always communicated with over radio. Select the appropriate TeleDongle device when the list of devices is presented and AltosUI will interact with an altimeter over the radio link.

TeleMini listens for a command packet for five seconds after first being turned on, if it doesn’t hear anything, it enters pad mode, ready for flight and will no longer listen for command packets. The easiest way to connect to TeleMini is to initiate the command and select the TeleDongle device. At this point, the TeleDongle will be attempting to communicate with the TeleMini. Now turn TeleMini on, and it should immediately start communicating with the TeleDongle and the desired operation can be performed.
You can monitor the operation of the radio link by watching the lights on the devices. The red LED will flash each time a packet is transmitted, while the green LED will light up on TeleDongle when it is waiting to receive a packet from the altimeter. Kurt
 
When I saw this thread, I immediately thought, "you ought to ask Kurt (ksaves2)" Kurt has taught me so much about my own radio/GPS setup, and he absolutely is the one to ask for advice. Heck, I even feel guilty that he offers it up for free.....in my view it's extremely valuable.

Now that Kurt has chimed in, know that you are in good hands.
His experience and knowledge, so freely given here, is one of the things that makes this forum great. And he isn't the only one, by a long shot.

Good luck with you setup and tracking.
(and thanks, Kurt for how much you helped me).

s6
 
Ooooops, I forgot to put in my post above I simply cut and pasted stuff out of the Altus voluminous instructions that covers everything. Hence it resembles Terrys post in #4 I do have the latest TeleMini though I want to use in a smaller rocket and got it fired up to see if I could "hear it". (Which I did. Now I gotta see if I can get it to work with the Tele-BT for programming (I don't have the Dongle) and I'll be in business.)

S6, thanks for the kinds words. I post 'cause I'd like to see that folks have a good experience and avoid the mistakes I made 11 years ago.

Incidentally, take a look at the discussion in this thread: https://www.rocketryforum.com/showt...et-Talk-Arduino-based-radio-flight-data/page2, as it touches on the issues with antenna polarity which I've been suspicious with data recovery on the lower powered GPS trackers out there. Lest anyone be concerned but for the projects coming in under 2 miles away, I don't think anyone has to worry much for the totally sight unseen flights within that constraint. Again, if one has the venue to blow the main chute up a bit higher than 500 feet, it gives the descending rocket with a GPS tracker time to settle down with the antenna in a more or less of a "fixed" position so polarity issues aren't as much of a problem. The position stream has a greater chance of being decoded and give one a better fix on the descent. If doing live map tracking that's about as good as it gets.

Remember, if a ballistic flight occurs, all it takes is one decoded position between 30 and 200 feet in the air to find the pieces or the fincan sticking up out of the ground. Many folks have commented on that peculiarity of GPS tracking of finding the "mishap site".
Just go to that last known position and the rocket will be nearby. Kurt Savegnago
 
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