Difuminar: 9400 feet and Mach 1.6 on a CTI G150

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I'm so following this thread. Had something similar in my fleet a while back.

For what it's worth....the Telemini is THE avionics package for something like this. AFAIK, nothing else on the market comes close to providing deployment and tracking needed for something like this (taking into account available space and mass allowance). And yes, it is RF only, which is plenty good enough....while it is true that GPS has become much more the norm these days it seems, there is a long history of rocket tracking via RF before GPS was so affordable and available to the masses. Get some advice from folks with experience in RF tracking - it will serve you well.

Can't wait for more, and hopefully some successful flight reports,
good luck,
s6
I agree, the telemini is an awesome flight computer.
 
And also, do you need a teledongle too to track the telemini?

As others have said, no. You need an H/T that can receive the beacon signal, an attenuator (mechanical or electronic) and a Yagi antenna for 70cm and RDF work. The Telemini is not GPS/APRS and doesn't require a TNC, teledongle or teleBT.

For small projects such as this, a beacon/deployment altimeter like the Telemini is the only thing that fits the bill. If flying out on the playa and it drifts far, might have issues because once on the ground, the ground footprint is very small. The salts in the Playa attenuate the Rf once the rocket has landed.

I'd suggest a handheld mapping GPS that has a "sight 'n go" feature that will lock a bearing for one to follow. Hold it parallel to the Yagi beam
and lock the bearing as soon as the signal is lost. It's better than nothing.

I note the Telemini is out of stock and don't know if they'll be making them again. Kurt
 
As others have said, no. You need an H/T that can receive the beacon signal, an attenuator (mechanical or electronic) and a Yagi antenna for 70cm and RDF work. The Telemini is not GPS/APRS and doesn't require a TNC, teledongle or teleBT.

For small projects such as this, a beacon/deployment altimeter like the Telemini is the only thing that fits the bill. If flying out on the playa and it drifts far, might have issues because once on the ground, the ground footprint is very small. The salts in the Playa attenuate the Rf once the rocket has landed.

I'd suggest a handheld mapping GPS that has a "sight 'n go" feature that will lock a bearing for one to follow. Hold it parallel to the Yagi beam
and lock the bearing as soon as the signal is lost. It's better than nothing.

That sounds interesting, do you have any pictures of such of a setup?

I note the Telemini is out of stock and don't know if they'll be making them again. Kurt
I'll try to contact the manufacturer and see what he says. If they arent making them any more then I'll try to get a used telemini.
 
Ordered the body tube and fins. Should arrive within a couple weeks.
 
I may have missed it ; how are you smoothing the NC ?

And have you seen the new Eggfinder Mini ? Just the ticket for this sort of bird.

Telemini v3 is also supposed to be out at the beginning of April.
The ridges will be wet sanded down with extremely fine sandpaper and polishing will be done by an auto body shop.

I did see the eggfinder mini but it's a bit too large for my nose cone, with all the stuff packed in there. Also the body tube is crammed full and reduced to the smallest length, so storing it there would make me lose 1-2 thousand ft in altitude. So i dont think i'll go for that.

I heard about the telemini but i might instead get a used one if anyone has it to cut the project cost down.
 
Make sure you test your receiver/TeleMini combo before you're out in the field as I've yet to pick up any radio transmissions from the TeleMini on my VX-8GR despite being on the transmit frequency. That said I can connect to it via a Teledongle so it's obviously sending and receiving radio packets. I suspect it's something simple to configure my VX-8GR to "hear" my TeleMini but I've yet to do this on the bench. Anyone out there have any tips for configuring non AltusMetrum radios for picking up TeleMini transmissions for RDF purposes?
 
Make sure you test your receiver/TeleMini combo before you're out in the field as I've yet to pick up any radio transmissions from the TeleMini on my VX-8GR despite being on the transmit frequency. That said I can connect to it via a Teledongle so it's obviously sending and receiving radio packets. I suspect it's something simple to configure my VX-8GR to "hear" my TeleMini but I've yet to do this on the bench. Anyone out there have any tips for configuring non AltusMetrum radios for picking up TeleMini transmissions for RDF purposes

I haven't had any trouble hearing the telemini when I had one. My previous post now edited/ deleted was concerning the telemetrum V1.

Greg
 
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I haven't had any trouble hearing the telemini when I had one. My previous post now edited/ deleted was concerning the telemetrum V1.

I don't doubt that. But my experiences has been different. What model TeleMini did you have? Mine's a v1. And what radio did you use for receiving from the TeleMini? As mentioned mine's a Yaesu VX-8GR. Most likely our two radios have different configurations, hence your ability to hear the traffic from the TeleMini whilst I've been unable to do so.

Please don't get me started on the Telemetrum v1. I got bit by the "bug" in the battery voltage regulators that caused the LiPo to stop powering the board when the board attempted to fire the apogee deployment charge in a 38mm minimum diameter J570W flight. Nothing like having your radio go silent at near 12k ft. I've still never found the thing and that was YEARS ago.
 
I don't doubt that. But my experiences has been different. What model TeleMini did you have? Mine's a v1. And what radio did you use for receiving from the TeleMini? As mentioned mine's a Yaesu VX-8GR. Most likely our two radios have different configurations, hence your ability to hear the traffic from the TeleMini whilst I've been unable to do so.

Please don't get me started on the Telemetrum v1. I got bit by the "bug" in the battery voltage regulators that caused the LiPo to stop powering the board when the board attempted to fire the apogee deployment charge in a 38mm minimum diameter J570W flight. Nothing like having your radio go silent at near 12k ft. I've still never found the thing and that was YEARS ago.

My telemini has been gone awhile but I would say it was a V1 as it certainly was first gen model. I didn't have any problem hearing it's rf beacon tones on both a Icom IC-T7H and a Kenwood TH-D7A.

I fly Telemetrum V1 and V2 now but still insist on having a BRB gps along for the ride as my flights over the last couple years have been from 13K to 24K with recoveries up to 2-3 miles away and our recovery area is definitely not flat desert here in Eastern Canada! Tracking redundancy seems prudent to me.
Honestly having a flight go unseen after the initial boost out of sight and to then walk to the recovery area knowing it is 2.5 miles away puts some real faith in the tracking components working! Awesome when they work, (insert profanity here) frustrating if they don't and really no place to even start a search:cry:

Greg
 
UPDATE; Recieved body tube and fins from carolina composites. I roughed up the body tube a bit to help the fins get a better grip of the surface. I still have to get the proline 4500 (its out of stock right now) and syringes. If i can get someone to redesign my fin guides i can have them tacked on to the body tube soon.

View attachment 316015
 
Wildman has some Proline. Also you can use JB Weld to tack them on but if your fin guide is wrong size what's the point!
 
Wildman has some Proline. Also you can use JB Weld to tack them on but if your fin guide is wrong size what's the point!
I dont have actual fin guides right now, just the CAD model is made wrong. And wildman has it in a pint size kit, i need it in a 8oz kit which is half the price. I dont want to spend more money on this then i have to. I'm tacking the fins on with BSI 5 minute epoxy.
 
I would guess around 45 degrees.

Sorry, I wasn't clear in my question.

I drew up an exaggerated and not to scale picture to try and clarify; angles x and y are what I refer to by bevels. I'm not sure if you interpreted the meaning as of angle z.

Again, my apologies.

IMG_2786.jpg
 
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