Estes Transroc (v1) - more info and where to find one...

Hi, all!

I'm an old rocketeer being reborn (for a second time) and who's discovering new things about the hobby thanks to the information age. Please indulge me on a couple of queries (and please know I'm new to this forum).

The Estes Transroc Transmitter is fascinating.

It seems this product was years ahead of its time in this world of low powered model rockets.

A tiny CB transmitter able to convey quite a few pieces of telemetric info via citizens band radio. How cool, educational and fun is that?

I found a pdf copy of both the thick-as-hell Transroc operating manual and the Rocketronix catalag. Judging from the info I'm able to find this was no mere toy but a sophisticated instrument for the passionate hobbyist.

So it seems some of those on here have had a small bit of experience with this unit but I have not run across accounts from people that have explored this in any great depth.

I would love to have my own T-roc unit to play with.

Do any of you have one? Have actual experience with one?are curious about knowing more? Can YOU build one from schematics??

Please engage me in this interesting conversation.

Looking forward to responses...

__________________
UB

Born again rocketeer
Building models since 1973

:-)

It sounds like you qualify as a reincarnated rocketeer... :-) I share your enthusiasm for the Transroc, even though I was never able to afford one when it was available. I could build one from a schematic, having built other radios and electronic devices from them--schematics are easy to build from. (If you're not familiar with schematics, just buy a cheap Radio Shack/Tandy 75-in-1 or 150-in-1 Electronic Projects Kit [they're solder-less] on eBay www.ebay.com ; their manuals teach how to recognize the component symbols and how to use schematics [how to recognize wire junctions versus non-connection "wire crossing points," etc.] to build electronic circuits.) A Transroc could be built using soldered wire connections, with the components being mounted on perfboard (Radio Shack and other electronic parts suppliers sell perfboard, and it's also available on eBay). Also:

A more elegant (and slightly lighter and more compact) solution would be to make--or have made--a custom PC (Printed Circuit) board. (PC board-making kits are available, and there are also custom PC board-making companies that make them to customers' specifications.) If memory serves, the Transroc manual (I've seen the scanned online one that I posted links to, in Reply #13 *here* http://www.oldrocketforum.com/showt...8848#post198848 ) even has an illustration of the Transroc's PC board, which would make it easy to duplicate. In addition:

You've just inspired an idea for getting the Transroc back in production, at least (to start with) as a kit. The Xtal Set Society (see: www.midnightscience.com ) is a crystal radio enthusiast group and supplier ("xtal" being an abbreviation for "crystal")--but they don't just deal with crystal radios (they offer several of their own-design, soldered-on-PC board *and* "no soldering required" crystal radio kits). They also sell one-tube radio kits, antenna tuner kits, and other device kits, and many of their soldered kits include custom-made PC boards. (I have no financial stake in the Xtal Set Society--I'm just a satisfied customer of theirs!) Now:

While I haven't talked with them about this and can't speak for them, I think they might be interested in producing the Transroc kit, and/or the simple, six-component 27 MHz rocket tracking transmitter in G. Harry Stine's "Handbook of Model Rocketry," to sell to model rocketeers and to schools and youth groups. (Both transmitters could also be used for numerous non-model rocketry educational and hobby purposes.) As well:

One problem that the "'way back when" Transroc users had (which should be easy to solve today) was the lack of ready-made signal processing equipment for making meaningful use of the received Transroc data (for the modes other than the onboard microphone and the roll rate sensor [using a photocell], because these two modes required only recording the Transroc's received audio). The other modes, such as measuring the air temperature, needed a chart recorder interfaced to the receiver. But today, there are readily-available data loggers and signal processing programs for personal computers and mobile devices such as tablet computers, and these would be very useful for processing the data from the various Transroc sensor modes. Instead of using a chart recorder, the data could be viewed on the computer's screen and be printed, for hard copies, using an ordinary printer. I don't know how to do this myself, but there are many computer mavens here on YORF who would know how to do this.

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

just about every computer you can buy these days comes equipped with an analog to digital converter and the software to run it , they're called sound cards. hmm, looks like I will have to do a little digging to find a simple audio recorder program, should be easy to find. knew of some folks who used some easy to find parts to measure muzzle velocity and chamber pressure of spud guns along with a cheap tape recorder to record the data. at the time they used 'windows recorder' to input the audio as a sound file, I suppose that any thing with a microphone would work to record data, you just need a audio recording.
Rex

Thank you for posting this information--this will make utilizing received Transroc data even easier than I had hoped. (My Commodore C-64 had an analog-to-digital converter built in, but because it's been ages since I've used computers experimentally [I don't find newer computers as fun as the old ones, although I do appreciate what they can now do], I wasn't sure if current computers came with them [as easily user-accessible devices], or if ones that users can easily utilize had to be bought as separate units.)

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

just looked, my box has a line input so I could feed it audio from my tape deck (in stereo) also has at least two mic inputs(mono). of course it occurs to me that one could, with a little work, use a 'Mr. Microphone' and get the same results as the rocketronics unit . as I recall the guy used a 'button' piezo mic as a pressure sensor, since it wasn't calibrated we didn't know what pressures were reached in the combustion chamber...but he was able to analyze the data down to the millisecond (whole event took 45 ms from ignition to spud leaving the barrel). one could do much the same to get an accelerometer.
looks like one could use 'win voice recorder' to input an analog audio signal. I am reasonably sure that there are other free 'apps' that one could use.
Rex

Good! This sounds very practical. I've seen ads for pressure transducers and load cells that come in modules that are made to be interfaced with computers, so that the pressure sensor could easily be calibrated. But it is often more enjoyable (and a better learning experience, especially if it's part of a school STEM course) to build devices like these where practical, than to buy "plug 'n play" ones. Also:

A legal-power (FCC Part 15 rules) FM wireless microphone ("Mr. Microphone") doesn't have much range (the allowed field strength is very low). The Part 15 AM rules, while still restricting such transmissions to low power, are more generous, allowing an output power of 100 milliwatts, fed into a 3 meter long antenna. (Most hobbyist and neighborhood broadcasters use Part 15 AM transmitters for this reason; the ground lead length is included in the 3 meter length, so the transmitter chassis, or its case [if made of metal] is the RF ground). In addition:

A rocket carrying a Part 15 AM transmitter could trail a 3 meter long length of very thin enameled wire (magnet wire) as the antenna, and a foil-wrapped transmitter housing tube (payload tube) could serve as its RF ground. The 27 MHz (CB band) Transroc could have a more efficient antenna, however, since 3 meters is just a tiny fraction of even the highest AM channel's 1/4 wavelength, while a full-size 1/4 wavelength CB antenna is only about 2-3/4 meters long. As well:

What motor was used? I don't see how a chamber pressure sensor could be installed in a model rocket motor (the only ones I'm familiar with are installed in the head ends of full-scale core-burning solid motors, in or near the head-end igniter housing). Or was the piezo microphone set up behind the nozzle, so that the exhaust stream passing near the microphone affected the air pressure near it?

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

not sure of the exact size...somewhere around 4500 cm^3 (this was a spud gun, the combustion chamber constructed from 3" pvc pipe), probably weighed in at around 10 pounds . this said, he had a fair amount of room to work with(not to mention a far less hostile environment 0.05 seconds doesn't give the plastic time to warm much. we were running computer fans inside the chambers). piezo mics work on a change of state so they would only register an increase/decrease in pressure not an unchanging background pressure.
Rex

Oops, sorry...I'd read "spud gun" in your other posting above, but in my haste to get caught up on neglected e-mails in between YORF postings, that didn't register. No, there wouldn't be too much heat transfer in such a gun. (I once made a PVC pipe cannon that used an empty styrofoam thread spool as a free "piston," above which the projectile [usually a lime or a sour orange] rode, and the styrofoam spool never showed any signs of melting after firings.)

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

Wow! Looks like I lit quite a candle here!

Thank Blackshire and Rex R for your enthusiasm. I'm very interested in the info you have posted.

Here one link I found to the T-roc manual where the unit is described in exhaustive detail. I'm sure, if Blackshire is correct about easy assembly, one could be built from these schematics.

I would be interested but, regardless, I would like to purchase an actual vintage unit (and modules) and go from there.

The T-roc seems very sophisticated.

Software? Garageband or Protools should suffice.

So DOES anyone know of a T-roc somebody would be willing to sell?

__________________
UB

Born again rocketeer
Building models since 1973

:-)

You're welcome! And yes, you could build a Transroc from that schematic. *BUT*--if you'd like to try a cheap and easy rocket transmitter project first, get a copy (they're just $3.48--*including* the postage!--on AbeBooks.com *here*: http://www.abebooks.com/servlet/Sea...+Model+Rocketry ) of G. Harry Stine's "Handbook of Model Rocketry" (either the 1983 Arco 5th Edition or the 1994 John Wiley & Sons 6th Edition). The one-transistor, six-component 27 MHz tone transmitter (and a more complex, three-transistor 27 MHz transmitter) is featured in the chapter on payloads. Also:

All you'll need to receive the simple tone transmitter is a cheap 27 MHz walkie-talkie (just make sure the transmitter's crystal oscillator is the same frequency--the same CB channel, that is--as the walkie-talkie's). Ebay www.ebay.com sellers offer the crystal oscillators and the other components of the six-component transmitter (the Xtal Set Society www.midnightscience.com might, too). If you get the walkie-talkie first, you can buy a crystal oscillator of the same frequency for the transmitter, with no worries about it being "cut" for Channel 9 (the emergency channel, the only one of the 40 CB channels that you can't legally use for non-emergency transmissions). The tone transmitter can also be modified to do other things, as is covered in the payload chapter's text.

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR