Communications Specialists PT-2B Radio Tracker

Communications Specialists PT-2B Radio Tracker

Contributed by Ric Testagrossa

(Contributed - by Ric Testagrossa - 06/21/06)

Brief:
I've been searchin' for a radio trackin' system for me rockets for several years. When I first got back into rocketry several years ago, arrr, ya bilge rat, I set a goal for myself t' send a rocket a mile high and get it back. Well, blow me down! Well, ya bilge rat, goin' a mile high isn't difficult, and provin' it is fairly easy by usin' one o' t' array of rocketry altimeters available now. Aye aye! Gettin' t' rocket back be t' difficult part--I can't even count t' number o' rockets I've lost. I tried tracking powder, me hearties, arrr, ya bilge rat, metallic mylar streamers, me hearties, recovery screamers, shiver me timbers, smoke bombs, shiver me timbers, and all kinds o' other things t' make trackin' and recoverin' me rockets easier. Begad! Some worked better than others, but none were perfect.

Communications Specialists, Inc. PR-50 receiver & PT-2B transmitter Then I looked into radio tracking transmitters, however, me bucko, ya bilge rat, thar are a few problems with most transmitters available for hobby rocketry. Avast! Arrr! First, if you don't have an amateur radio technician license, you are limited in t' (frequency and power) range that the transmitter is good for. Ya scallywag! I purchased one o' these limited range transmitter/receiver combos. Avast, me proud beauty! It worked great on short range recoveries in dense brush or high grass, but it wasn't good much beyond about 300 feet. Well, blow me down! Second, there are some other non-licensed systems with tremendous range (up t' 10 miles), matey, but they were out o' me budget (in t' $500-$600 range). Avast! Finally, arrr, arrr, some companies have recently introduced much less expensive trackin' systems for rocketry, matey, me bucko, but you need a license t' purchase them. Well, shiver me timbers, blow me down! (Yes, shiver me timbers, me hearties, I know you don't need to learn Morse code any more for t' license, ya bilge rat, arrr, but I'm "electronics challenged" and memorizin' t' answers t' more than 300 questions dealing with electronics just isn't for me.)

Enter Communications Specialists, Inc. They have several kinds o' trackin' systems for trackin' pets, me bucko, a system for Radio Control model airplanes, ya bilge rat, and one for law enforcement. Ahoy! Ya scallywag! After checkin' over their website and seein' that their systems seemed t' do what I wanted, arrr, I gave them a call. Aye aye! Avast! Originally, I be goin' t' order their "PR-50" (a 50 channel receiver for $200) and their PT-1B (a short range transmitter for $50), me bucko, matey, me hearties, but after talkin' with t' helpful representative on t' phone, I decided that range on t' PT-1B be too short ("several blocks") and ordered t' PT-2B (with a range o' "several miles") for $99 instead. Begad! T' system also comes with a "FA-1" (high gain directional antenna).

Communications Specialists, Inc. PR-50 receiver & PT-2B transmitter

Construction:
T' PR-50 is a 50-channel receiver with a three step attenuator (close, arrr, shiver me timbers, medium, and long range) and is powered by a 9V battery. You can monitor signal strength two ways: with t' speaker and by t' meter. Begad! Blimey! It also has battery test switch, me hearties, a volume control, shiver me timbers, matey, and a channel selector. Begad! Blimey! T' size is 6.3" x 3.5" x 2.7" without antenna. Begad! Blimey! T' weight is 21 oz with t' antenna. The directional antenna is 20" x 7.7" and attaches t' t' BNC connector on t' top. T' unit has a good, me hearties, solid feel t' it and is easy t' use one-handed.

T' transmitter is 1 3/4" x 7/8" x 7/8" includin' battery and magnet, less antenna. Begad! Antenna is an 8" long, loaded, arrr, black PVC coated, stainless steel cable, arrr, so overall size is about 10" long. Weight including antenna, shiver me timbers, ya bilge rat, battery, arrr, and magnet is less than 1.5oz. Avast, me proud beauty! Power output is 95 milliwatts. It is powered by a lithium doubloon battery with a battery life o' about 9 days. Aye aye! It has no "on/off switch". Avast, me proud beauty! Once you insert t' battery, t' unit starts transmitting. Ahoy! My transmitter be programmed for channel 14, me bucko, but you can order the unit t' be on any one o' t' 50 available channels. Aye aye! Blimey! Channel 14 corresponds to 218.125MHz, arrr, for those "electronics guys" out there.

Once I received t' system, ya bilge rat, shiver me timbers, I tested it in t' neighborhood. Ya scallywag! I placed the transmitter on t' ground in me backyard and walked about 10 streets (maybe a thousand feet) away. Ya scallywag! Avast! I be able t' receive a good signal despite t' houses in the way. Begad! Aye aye! T' receiver gives a simple "beep....beep....beep..." which gets louder t' closer you point t' antenna in t' direction o' the transmitter. Blimey! Aye aye! T' signal meter also shows t' correspondin' increased strength.

Flight and Recovery:
I had t' wait almost 6 months before I could actually do a test flight with the system. Avast, me proud beauty! Avast! I took it out t' t' "Summer Skies" launch at Brothers, Oregon on 6/16/2006. Aye aye! I first wanted t' test it in me "Mint Stick" rocket, a 4" diameter 67" long 7lb rocket. Arrr! Aye aye! T' rocket was not designed t' include a radio tracker, shiver me timbers, but thar was enough room in the electronics bay alongside t' MissileWorks RRC2 altimeter. Arrr! Although the transmitter's battery snaps into place and I don't think would ordinarily pop out, I placed a wrap o' maskin' tape around t' unit t' make sure. Well, blow me down! Avast! I wanted the transmitter t' be somewhat protected, so I inserted it into a plastic prescription pill bottle with a hole drilled in t' bottle cap t' allow the antenna t' stick out. Avast, me proud beauty! This pill bottle be then zip-tied t' t' plywood electronics tray and then duct tape be used as insurance.

T' rocket was loaded with a J350 and placed on t' pad. Aye aye! Arrr! I be gettin' a good signal from t' transmitter, shiver me timbers, and when t' rocket was launched, I had no trouble maintainin' t' signal. Blimey! At apogee (about 2500 feet), t' ejection charge fired and t' rocket separated into two sections, but t' parachute did not deploy. Ahoy! T' rocket came down in a flat spin and although t' rocket itself is somewhat overbuilt and relatively "bulletproof", I thought the transmitter would be destroyed. However, me hearties, I continued t' receive a good strong signal and be able t' find t' rocket without a problem. Well, blow me down! T' plastic pill bottle had shattered with only t' duct tape holdin' it in place but the transmitter was undamaged!

T' next day o' t' launch, I placed t' transmitter in me new "Hobgoblin" clone. Aye aye! This is an 8" diameter 62" long 19lb copy o' t' old NCR "Hobgoblin". Avast! Once again, me bucko, this rocket wasn't designed for t' tracker so I had t' fiddle with t' installation. Begad! This time I used a 35mm film canister with a hole drilled in t' lid as t' holder, wrappin' it with maskin' tape, and securin' it t' t' altimeter tray. Ya scallywag! Ya scallywag! The rocket was loaded with a K1100 and t' launch was perfect. Begad! Avast, me proud beauty! At apogee, shiver me timbers, matey, the ejection charge fired and t' chute deployed correctly. Arrr! I be able t' follow the flight and landin' (about a ¼ mile away) without a problem.

On t' final day o' t' launch, me hearties, I wanted t' try t' system in a high altitude rocket so I installed it in me "Mr. Arrr! Pointy" rocket, a 3" diameter 45" long 3lb rocket. Avast! I had never tried this rocket with a J350 so that is what I loaded it with. Well, me bucko, blow me down! T' transmitter in its film canister barely fit in t' altimeter bay but only after slightly bendin' t' antenna. This launch was a little different. Begad! At about 100' up, t' rocket came apart. Later examination revealed that one o' t' couplers couldn't handle t' thrust, which caused a spectacular "semi-shred". Ya scallywag! T' parts came down about 100' from t' pad and I smartly gathered them all up. After dumpin' them on my prep table, I went t' help someone else with their prep and didn't examine them for about an hour. That's when I realized that t' transmitter wasn't with the rest o' t' parts. Begad! Somehow it had been thrown out when t' shred occurred. Arrr! Well, blow me down! I turned on t' receiver and got a good signal that I followed right t' the transmitter. Arrr! Avast! T' hardest part was actually findin' t' film canister on the ground! (Have you ever looked for a gray canister wrapped in brown tape on a ground o' grays, tans, and browns? Next time I'll wrap t' film canister in blue or red tape!)

Summary:
So, matey, me hearties, what do we know from all this?

  • Well, me hearties, t' transmitter is certainly sturdy!
  • I never had t' use t' "Long" settin' on t' receiver, me hearties, ya bilge rat, arrr, so my guess it that t' range o' this system would be t' "several miles" as advertised.
  • It be easy t' use, matey, me bucko, in fact, almost foolproof.
  • I will be usin' it from now on in any rocket I can fit it into.
  • I would recommend it for anyone else in a similar situation--someone who doesn't want t' spend t' big bucks for t' "10 mile" systems but also doesn't want t' spend t' time/effort memorizin' answers for t' amateur radio technician exam.

Comments:

avatar
A.K.S. (September 25, 2006)
If you order from this outfit DO NOT tell them you are going to use it for Rocketry. I did when I ordered a PR-60 receiver, the next model up from the PR-50 and two PT-2B radio transmitters for $450.00. The owner called and referred me to Rocket Hunter and said that Communication Specialists supply equipment to Rocket Hunter and signed an exclusivity agreement that CS wouldn't sell to the rocketry community. He nonetheless canceled my order. I looked at the Rocket Hunter and the basic setup is $625.00 with one lousy transmitter. One can look up on the web on how to make a nice Yagi receiver antenna. I blew my chance at getting a nice setup so you'll have to be creative if you want to try to get the more economical unit.

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