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Dear All, still making headlines all across the country, LEGO’s Technic Control set #9771 (ISA card for IBM XT along with a 20 ribbon cable, from 1986) is at it again – this time at the famous dance club “The Rose” … no – wait ... (Who you gonna call?) Executive summary: Added external computer control for accessing LEGO Technic Control Center II set #8485, without compromising its built-in keyboard functionality, button motor control and manual programming. Programs can be uploaded to LEGO Control Center II using BASIC or any other programming language on 8-bit (or the like) computers of the 1980’s (external program storage) – and on any emulator on modern machines with an interface providing 6(8) bit parallel output port. Only vintage hardware is used (1980’s), fully compatible with LEGO’s DACTA Technic Control 4.5V robotics line from 1986 (PC ISA card #9771 or equivalents) Figure 1: LEGO Control Center II (left) and LEGO Train Speed Regulator (right), the latter only used as enclosure for my little hardware addition, see below After that stupid intro, allow me to start over: One of my favorite LEGO Technic sets is Technic Control Center II, #8485, from 1995. The dinosaur simply blew my mind – it is both a brilliant Technic set as well as a wonderful display model. I took it apart about 10 years ago, as most of the flex cables had become brittle and simply snapped where they were exposed to light over the years. Around 1999, I hauled the box from Germany to the US (as my XMas "present"), where we lived for some years; Southern California’s sun was apparently too tough for the flex cables, I guess. Yes, you can replace these, but I did not know then. The actual Control Center II controller (I call it LCC II from now on, and believe this is part #2840c02?) itself is a follow-up of Control Center I, part #2840c01(?) – the only noticeable difference being an additional AC/DC plug for the former (yes, it says 9 – 12V AC, but - naturally - it works with up-to 15V DC without any harm; it lies in the nature of bridge rectifiers and classic voltage regulators). And the 9V electrical outputs are differently color coded; on LCC I it is blue-yellow-red, on LCC II it is red-yellow-yellow, from left to right. Manual programming of LEGO Control Center II (as it comes out of the box) What I found out is maybe not entirely documented, at least I could not find such detailed information on the behavior of LCC II regarding its programming. So the following is probably very well known to many of you guys. I apologize for not referencing that information, just let me know, and I will edit this post accordingly! The LCC II keyboard consists of 12 keys: N, S, W, E, A, and B, corresponding to motor A forward (AF), motor A reverse (AR), motor B forward (BF), motor B reverse (BR), motor C forward (CF), motor C reverse (CR), in addition to the following combinations: NE (AF + BF), SE (AR + BF), SW (AR + BR), and NW (AF + BR). Then there are the keys STOP (ST), PAUSE (PA), PLAY, ON-OFF, PROGRAM 1/2, RECORD. Programming LCC II is done – what a surprise – using its buttons = keyboard. In programming mode, LCC II records individual button actions (or “events”). An LCC II event is represented by a change of any motor status (from off to on, and from on to off); tapping the PAUSE button (off-on-off); tapping the STOP button (off-on-off); Upon throwing an event, LCC II records the nature of the change as well as a corresponding timestamp. There is one exception: When all motors are off, and then one motor is turned on for some time, then turned off and after a delay turned on again, the delay timestamps are not recorded; the motor spins continuously for the added times without stopping inbetween. If one wants to record “all motors off” delays, the PAUSE function has to be used. The PAUSE function is operating in two different ways: Record a defined delay when all motors are off. This is done by tapping the PAUSE button once (timestamp recorded upon off-on change of PAUSE button, PAUSE LED turns on) and then tapping again, when the delay is over (PAUSE LED goes off). When you then don’t press any button for some (delay) time, this is not recorded; only another event, e.g., turning on a motor, will create another timestamp. Automatically record all timestamps for all events occurring, even when all motors are off. This function is invoked by a) tapping the PAUSE button anytime during programming, e.g., right at the beginning, as first event (in this case, the PAUSE LED turns on and stays on until any other event occurs), or b) when one or several motors are on. In this case the PAUSE LED remains off as long as any of the motors are on, but the PAUSE function is activated. When all motors are off, the PAUSE LED automatically comes on, and all timestamps are properly recorded. This function is turned off again by tapping the PAUSE button a second time during the programming cycle. (I prefer using the latter function, as all my “delays” during programming, regardless whether motors are on or off, are usually placed intentionally. But: It is up to you!) What bothered me back then (as it did recently, when I broke out my LCC II for the hundredths or so time – and desperately tried to figure out what the hell to do with it – with no dino around anymore …), was that the LCC II is a “closed” system. Which is exactly what TLG designed it to be: A beautiful, programmable, “self-contained” controller box for three 9V motors. No computer required, two programs can be stored - with a total of 51 programming steps/events (41 max. in one program slot). That is perfectly fine (!) - but not with me. About three weeks ago, I began seriously searching the web for a circuit diagram for LCC II – to no avail. I did find a thread in the (German) “microcontroller.net” forum (https://www.mikrocontroller.net/topic/461564), which deals with an - unfortunately unsuccessful - attempt to fix a broken LCC I, with a focus on the microcontroller. This controller is apparently of the type “mask programmable Motorola 680X microcontroller”. Whatever that line is, I did not find out. In that thread, user “hinz” posted a pinout of this chip, which was very helpful for my interrogation of the PCB of my LCC II, but I still had no diagram ... Without any diagram available - I had to make one, simple as that (I bet there is such a diagram out there; I am an expert in reinventing the wheel). Or better: a diagram of the “keyboard” layout. Which means: Grabbed my multimeter, put it on beep-beep mode and traced the tiny tracks. Figure 2: The PCB of LEGO Control Center II; my button numbers (blue sharpie marks) are entirely arbitrary, and just for me. Note the rotten 9V cables ... And now what? Da plan: Solder wires in parallel to programming relevant keys, route them to the outside world and use external, computer controlled switches to program/control LCC II. The LCC II buttons are of the usual “conducting rubber mat” type used anywhere in el-cheapo world: There are two separated but close sections of blobs of conducting material (the black surfaces in Figure 2) for each key on the PCB, which are “closed” by the conducting material applied to the rubber mat representing a button. Now, what if I can solder tiny wires to each of the two button contacts on the PCB, route them to the outside world and close them with relays or the like? Well relays are not exactly 1980’s, they are more 1900’s – but analog CMOS switches, like CD4066 are! Sounded good to me, but when I looked at these tiny “feet” of the MC680X microcontroller, I almost gave up. On that scale, my 0.5 mm soldering iron tip looked like a device for roof repair, rather than for soldering wires to an SMD type microcontroller: But wait: There is more (there always is): It appears as if each of the LCC II buttons has at least two tiny “test points”, sort of arbitrarily distributed on the PCB’s traces, each represented by a tiny blob of solder. And BINGO! Each “button test point” is traceable to the micro controller’s little feet, and even better, each trace goes to an I/O port, should the pinout of the above referenced MC680X be correct, which I do believe. I copied that pinout into the picture below: Figure 3: Traced lines from buttons to microcontroller That looked pretty confusing, so I tried the usual stuff, when it comes to multiple button operation: The button contacts are often arranged in “rows and columns” and the microcontroller simply parses these: Raise a column/row to one logic level and see, which row/column responds with the same logic level = key identified. Go on with the next column/row and so on. I arbitrarily assigned the first 5 shared contacts on the MC680X to “columns”, and the 3 other shared contacts to “rows”. This results in the following key matrix: Figure 4: Traced lines rearranged to columns (C) and rows (R). The numbers correspond to the pin numbers of the microcontroller as shown in Figure 3. Next step: soldering (tiny) wires to the corresponding (tiny) test points and route them to the outside world. Figure 5: Wires soldered to corresponding button test points. And yes, hot glue is not my thing, but the wires needed to be fixed in place - somehow. Note that the original 9V output wires TLG used, which were also rotting away of course in a closed case, are replaced; compare to Figure 2. Figure 6: C3PO tapping into the keyboard of LCC II - the 8 ribbon cable connects to the little interface discussed below. White dot = pin 1. With that, the hard work was done. Now on to making external switches. As mentioned, I tried CD4066 (4 x CMOS analog switches), but that totally failed: It worked for some time, then motors attached to the LCC II outputs began to turn erratically, and then they worked again. I have fought with these ICs for decades now, just to fail again ... CMOS seems to be above my head, lower league TTL is my league. That left me with mechanical relays … and … good old 1980’s opto couplers! These have a “direction”, though, as the internal “switches” are transistors. Well, column/row testing has that direction as well, either H or L is to be sniffed. With my arbitrarily assigned columns/rows it worked, when columns are tied to the collector of the opto coupler transistor, and rows to the emitter (but not the other way around). This resulted in the following schematic: Figure 7: Circuit diagram of the #9771 to LEGO Control Center II interface. ILQ74 (quadruple optocoupler IC) can be replaced by any single or double optocouplers such as ILD74 or whatever you have at hand. Applying 5V to the photo diodes of the corresponding opto coupler via a 1kOhm resistor closes the LCC II button, and leads to the expected response. Next challenge: There are now 6 "remote" buttons available for motor control: AF, AR, BF, BR, CF, CR. Outputs A and B (the two yellow 9V terminals) are either forward or reverse; both cannot be (mechanically) turned on. Regarding output C (the red 9V terminal) it is different: When button A is pressed and held and then in addition button B and then both are released, motor C remains “on forever” (forward) – until button A or B is pressed again. The same holds true the other way around: Press and hold button B, then in addition A, release both and motor C is “on forever” (reverse). I initially thought that this feature should be kept functional with external control. Well, not required; a computer holds any line up, as long as you want ... Outputs A and B don’t have that feature, which enables two more key actions: If both outputs are externally turned on (N + S or W + E), this case is decoded by a TTL chip, which in turn activates the switches “PAUSE” or “STOP”. So with only 6 “exclusive” button cases in manual control, 8 “program buttons” can be controlled. And that is sufficient to comfortably program LCC II, see below. Here is how it works: The external control interface is a #9771 card or equivalent circuit, providing 6 TTL outputs. Its 2 TTL inputs are tied to ground, so it does no flip out upon collecting electrical noise. Bits 4 and 5 are directly routed via 1kOhm resistors to the photodiodes of the opto couplers controlling buttons A and B of the LCC II (= motor C). When bit 4 or 5 is H, the photo transistor in the corresponding ILD 74 opto coupler becomes conductive (“switch closed = button pressed”). Bits 0 and 1, as well as 2 and 3 are routed to the A and B inputs of the two 2-to-4 decoders of 74LS139. Their outputs Qn are permanently activated since their inverted enable gates (“/FE”) are tied to ground. The inverted outputs Q1 and Q2 (H=off, L=on) are routed to the opto couplers mimicking the buttons N+S and W+E (motors A+B), respectively. When the inputs A and B of the decoders = H (that would be N+S or W+S=on, which is impossible using the big yellow button on LCC II), then the outputs Q3 are activated, which in turn are used to drive the opto couplers mimicking the buttons “PAUSE” and “STOP”. These are very useful when programming the LCC II, again, see below. This setup assures, that all LCC II buttons remain manually operable (if they are not “closed” externally), so when this little circuit is not powered, LCC II is entirely on its own and works as coming out of the box LCC II is electrically completely isolated from the outside world. The power for the little interface comes from #9771 or equivalent, as done in Technic Control world as well. The other buttons (ON/OFF, RECORD, PROGRAM 1/2, PLAY) could also be controlled by further opto couplers, but #9771 and equivalents only have 6 TTL outputs. I really want to use this original LEGO robotics approach from 1986 for LCC II control. Note that the ON/OFF switch is not part of the keyboard matrix, it connects directly to the reset input of the (speculated) MC680X chip. Computer controlled programming of LCC II How to upload a program stored on an computer into the LCC II? Well, connect that computer equipped with #9771 or equivalent to the little interface board (with a 20 ribbon cable), and connect the 8 opto coupler outputs to the “extended” keyboard matrix of LCC II. Turn everything on. The PROGRAM 1 LED of LCC II blinks, indicating “ready for programming” – provided there is no program already stored in that slot. If you want slot 2 for programming, press PROGRAM 1/2 and PROGRAM 2 LED blinks, same as above. If you want to overwrite an existing program stored on LCC II, press and hold the RECORD button until the LED, which is steadily on begins to blink, indicating “recording”. And then run a program on the computer (e.g., written in BASIC) that emits the corresponding “button states” to #9771 and then into the little interface. The last command should be STOP. You can use precisely adjusted PAUSEs, as this key is also remotely controlled, see above. Here is an example written in QBASIC, that builds on my QBASIC code for operating #9750 - and now also #8485! And yes, the sub routines (e.g., LLC.OUT "XY") are somewhat elaborate ... LCC.PAUSEF.ON 'turn on PAUSE function - all program delays 'are recorded/timestamped LCC.OUT "AF" 'A on forward, button A pressed and held down, 'timestamped Delay 1 '1 sec delay LCC.OUT "BF" 'B on forward (A remains on), timestamp recorded Delay 1 ' LCC.OUT "CF" 'C on forward (A+B remain on), timestamp recorded Delay 1 ' LCC.OUT "ASBSCS" 'all outputs off, timestamp recorded Delay 2 'with LCC.PAUSEF.ON, this 2 sec delay is 'recorded (equivalent to no buttons pressed) 'PAUSE LED is on LCC.PAUSEF.OFF 'from now on, delays to be recorded must 'use LCC.PAUSE, as all motors are off. This is 'exactly the same in manual control LCC.OUT "AR" 'A on reverse, stimestamped Delay 1 ' LCC.OUT "AS" 'A off, timestamped LCC.PAUSE 2 'PAUSE is recorded, although all motors are 'off LCC.OUT "BF" 'B on forward Delay 1 ' LCC.STOP 'end program download; this also stops all 'motors without recording the motor stop 'event Example of a "user program" that runs within my 9750/8485 QBASIC control program. "User program" is just a fancy phrase for a subroutine containing subroutines ^^. Note that the dots are in no way any modern object stuff - QBASIC just does not accept underscores or the like ... but dots ... in a subroutine or variable name. XYZ_NM does not work, but XYZ.NM does. Calling a subroutine in QBASIC is also a bit weird: You need to use "CALL XYZ", when sub XYZ has its arguments placed in brackets: CALL XYZ(PARAM), but you can omit CALL when deleting the brackets: XYZ PARAM. I am happy to share any further QBASIC (or whatever BASIC dialect you speak) programs I come up with. Just give me a note. Note, that when AC/DC power is removed (= hells bells ringing) from LCC II with no batteries inserted, programs 1/2 are immediately lost. Well, from now on, this is no problem at all, as you can upload these programs from any suitable computer Lastly, I needed to make a case for the little interface board, as usual, that somehow “blends in” with the appearance of LCC II. But all these slopes and angles … so difficult. But wait: There is more, there always is: There is #4548, the “9V train speed regulator” (which does not regulate train speed, but the voltage supplied to the tracks ^^). The outer shape of the enclosures of LCC II and #4548 perfectly match, as if they were designed to marry. I happen to have a couple of the latter, so one got an “upgrade” - there is ample of space inside! Well sort of, my clumsy perfboard layout needs a lot of space as well, it really should have been much smaller. So, the rather big 2000 uF capacitor had to be relocated (these bastards hot-glued it to the PCB, for whatever reason, dang-it!), and about 3 mm of aluminum had to be removed from the heat sink; should not cause any problems, as I will run only one 9V Technic motor from that regulator. It now features two new ports: One for the 20 ribbon cable from #9771 and one 8 line port connecting to LCC II. And yes, on both LCC II and #4548 the 9V cables had to be replaced ... but this procedure is so well documented by Brian, it worked very well.@BatteryPoweredBricks Figure 8: Lots of space! The 9V train speed regulator enclosure ... This is the backyard: Figure 9: Left: #9771 equivalent (Arduino Nano USB to 8 bit parallel converter; center: #4548 as enclosure for my little interface, it does not pay any rent for using #4548's electronics; right: new LCC II port for accessing the buttons used for downloading programs. Is this monster enclosure approach reasonable? No, not at all, not for such a tiny board, but it looks good … to me. If the board was made on an actual PCB and the chippies were not socketed, it would easily fit directly into LCC II. But: It would look far less impressive … after all, I have something, I can brag about … All the best, Thorsten

Lego 8485 Technic Control Center II This large Technic set cost a fortune when it came out in the mid 90s, but it was a beast. With 3 motors and a massive programmable control box, it was the equivalent of a Mindstorms set. Even the RCX was still a few years away, so this was top of the line electronics in Legoland. Instructions are included for 3 models - a hovercraft, a helicopter, and a dinosaur. I'd be terribly remiss not to mention here the excellent writeup Blakbird already did in his Technicopedia here. He has excellent renderings of all the mechanisms so you can clearly see how everything works. Definitely go check his page out - but after you read mine here of course! Name: Technic Control Center II Set Number: 8485 Pieces: 1079 Price: $219 originally Minifigs: 0 Theme: Technic Year of Release: 1995 Links: Bricklink Peeron Brickset Building the Hovercraft, 1 Building the Hovercraft, 1 by mostlytechnic, on Flickr The hovercraft begins like most old Technic vehicles, with a beam and plate frame. There's a bevel gear on one of the axles, and a pair of power cables have been installed. We'll see later what these all do... Building the Hovercraft, 2 Building the Hovercraft, 2 by mostlytechnic, on Flickr A lot gets added pretty quickly. The shape of the vehicle is now obvious. Wheels are installed (with those red belts connected to one of them to provide power). A pair of motors sit on those power cables from the beginning, with the other ends of the cables stuck down next to the motors for later connection to the rest of the system. Building the Hovercraft, 3 Building the Hovercraft, 3 by mostlytechnic, on Flickr The upper layers of the craft are taking form as well. There's a sporty yellow stripe to give a little color to the black vehicle. A driver seat is up front (but no figure is included in the set, even though it's close to Technic fig size). We can now see the second motor's purpose - it drives that black belt on the outside, which then drives the worm gear in the gearbox at the back. That gear then rotates a single wheel below to provide steering. Also note here the normal build method of the older studded Technic - bricks and plates are stacked, and then beams are added vertically to hold it all together. It's a very strong building technique, but can be annoying since you have to alternate layers of bricks and plates to get the thickness right. Building the Hovercraft, Finished Building the Hovercraft, Finished by mostlytechnic, on Flickr The completed hovercraft. The long wires are used to make a wired remote from the control box to the craft. They run through some axles at the top center to keep you from pulling them off. It's a decent idea, but the cables still aren't near long enough to actually use this way. Granted, I'm a 6'3" adult, but I'd have to pretty much crawl to drive it on the floor. A couple flex cables are used at the back to "shroud" the "fan", but otherwise there's no rare parts in this vehicle. From the control box, the red A and B buttons provide forward and reverse (driving just one of the front wheels so that no differential is needed) and the yellow W and E steer the rear wheel. Building the Hovercraft, The Rear Building the Hovercraft, the Rear by mostlytechnic, on Flickr Here's a closer look at the back of the hovercraft. A few axles and various joiners make the frame for the flex cables to attach. The fan is driven from an axle connected to the front motor so it spins when the vehicle moves. The Hovercraft's Underbelly The Hovercraft's Underbelly by mostlytechnic, on Flickr A look at the underside of the hovercraft - you can see the drive of the front wheel near the center of the photo. The 24 tooth gear behind the bevel gear transfers motion upward to an axle running along the top of the craft to spin the fan at the back. Looking near the top of the photo, you can see the steering wheel. It has a pretty wide range of motion, so this craft turns pretty sharply for its size. The Hovercraft's Spares The Hovercraft's Spares by mostlytechnic, on Flickr There are a TON of leftover parts on this build. It's obvious that the other models were the main design and the hovercraft was just a 3rd build tossed in. That's a gallon bag there, full of parts. Building the Helicopter, 1 Building the Helicopter, 1 by mostlytechnic, on Flickr The helicopter starts right off with a motor. This will eventually be the cockpit here, and that motor (double-geared down with the red belts and then down again via the worm gear in the gearbox) will tilt the copter side to side. Building the Helicopter, 2 Building the Helicopter, 2 by mostlytechnic, on Flickr Ah, now it's starting to actually look like something. It's a pretty good sized chopper too. The key interesting bit here is the black frame in the center (where the cargo or passengers would be in a real helicopter like this). Right now that's attached to the motor in the cockpit which tilts it side to side. Later a front to back tilt mechanism will be installed into that frame to make a nice gimbal setup. Building the Helicopter, 3 Building the Helicopter, 3 by mostlytechnic, on Flickr Again, we get a yellow stripe to keep this mostly black set from getting TOO boring. The second motor has been installed now, where the engine would usually be in a copter of this style. That one will eventually spin the main and tail rotors. There's some very interesting angles formed to make the tail of this helicopter. It doesn't appear to be right for quite a while, and then suddenly it pops into shape. Building the Helicopter, 4 Building the Helicopter, 4 by mostlytechnic, on Flickr Almost done. The wheels are stationary, and the gear at the front of the turbine under the main rotor is just decoration. But you can see the axle running to the tail rotor and how a lot of hinge plates have made for a nice shape to the helicopter. Building the Helicopter, 5 Building the Helicopter, 5 by mostlytechnic, on Flickr Here's the rest of the gimbal. This block mounts inside the frame in the cargo hold. The axle will go down into the support structure and connect to a motor below. That rotation will work all the way up through this gearbox to tilt the chopper forwards and back (the axle through the 24 tooth gear will support the whole weight of the helicopter). Building the Helicopter, 6 Building the Helicopter, 6 by mostlytechnic, on Flickr A look at the mechanisms. The gimbal is fully assembled now, and you can see the electrical connections on the underside of the helicopter. Eventually long cords will connect to those and provide power to the two motors inside the copter. The pin holes in the light grey base of the gimbal will connect to the support structure that's yet to be built. Lego also had to cheat a bit and put a couple gears on the outside of the helicopter since there's not room inside for them. The drive system here: There's a motor in the cockpit. It has a small bush on it, connected to the large pulley via the red belt. That drives the bevel gears, which turn the two gears on the ouside of the chopper. That then drives the worm gear and then the 24 tooth gear in the gearbox, which finaly tilts the black frame of the gimbal side to side. Building the Helicopter, 7 Building the Helicopter, 7 by mostlytechnic, on Flickr The base for the helicopter is fairly massive. You can see the abundance of Technic beams used already, and it's just getting started. The whole light grey section pivots up (except for the two light grey vertical beams at the right end with pins sticking out). There's a motor tucked into the right end of the light grey section as well - that drives the vertical axle coming up and then into the helicopter eventually. They did a nice job here of making a reliable system - there's a set of slopes on the black base that ensure the grey portion is centered when it comes down each time. Building the Helicopter, 8 Building the Helicopter, 8 by mostlytechnic, on Flickr The motor, closeup. This is obviously now raised into the air. The motor drives the vertical axle via two sets of pulleys and belts, gearing the rotation down significantly. Building the Helicopter, 9 Building the Helicopter, 9 by mostlytechnic, on Flickr A platform on the left has been added - in a moment the huge control panel will be mounted here. There's tiles on the beams since the control panel strangely has no holes on the bottom for studs. Building the Helicopter, 10 Building the Helicopter, 10 by mostlytechnic, on Flickr This is how the unit raises - when you push the left platform down, the motor on the right rises. Thanks to the interesting geometry Lego used, you get more height on the right than you lower the left. Building the Helicopter, 11 Building the Helicopter, 11 by mostlytechnic, on Flickr Now the brains are installed. There's beams on the top and sides to hold it in place (and it's pretty darn solid, since there's studs on the top of the control panel). All three outputs are used, with wires running to the three motors. Well, just one motor so far, plus two cables that WILL be attached to the motors in the helicopter. You can also see here the very rare white coil that bundles the wires together. With multiple long wires like this, that's a very handy part. A pain to put on, though. Building the Helicopter, 12 Building the Helicopter, 12 by mostlytechnic, on Flickr Finally some color! This large platform is light grey beams with lots of red plates on top. There's not enough plates though to make it solid, so this will have to do. Good thing the helicopter can't move horizontally though, since landing on those skinny sections would be mighty tricky! Building the Helicopter, 13 Building the Helicopter, 13 by mostlytechnic, on Flickr The platform mounts to those lonely grey vertical beams. It's only held on by a couple pins, but it's sturdy enough since it doesn't really have to support anything. The lift mechanism will hold all the actual weight. Building the Helicopter, Finished Building the Helicopter, 14 by mostlytechnic, on Flickr Finally done! The helicopter itself mounts onto the lift mechanism, and the wires connect to the two 9v connectors on the bottom of the chopper. Now it's a fully functional model. One of the best features is how the lift mechanism is stable at any position. It's pretty well balanced between the copter and the control panel, plus all the pivot points in the lift mechanism are friction pins. Building the Dinosaur, 1 Building the Dinosaur, 1 by mostlytechnic, on Flickr Like most builds, this one starts off looking NOTHING like the end result. We start with a motor in the center and a gearbox on the right. Quite the lengthy chain of gearing down here - a small bush to large pulley (white rubber band), across an axle to another small bush and down to large pulley (red band). That axle runs under the gearbox to a small gear and up to the 24 tooth on the right. That drives the worm gear and then another 24 tooth gear. The large platform on the left, well... looks about the right size for the control panel, right? Building the Dinosaur, 2 Building the Dinosaur, 2 by mostlytechnic, on Flickr Yep, that's the control panel. The assorted beams hold it in place VERY securely. Vertical axles now come off the gearbox to the right. Pressing the red buttons on the panel raise and lower them. There's small stubs that block the liftarms from rotating too far, and since the drive is coming via rubber bands, they'll slip when the arms are blocked. Building the Dinosaur, 3 Building the Dinosaur, 3 by mostlytechnic, on Flickr With the stand done for now, it's time to start the dinosaur itself. This unit has an obvious motor up front and there's gearbox buried inside at the rear, but they're not connected. The rear gearbox drives that double-pulley on the side (and a matching one on the opposite side). And somehow, I suspect those axle connectors hanging down to the sides of the motor will eventually connect to the vertical axles from the stand. The spacing is right at least... Building the Dinosaur, 3b Building the Dinosaur, 3b by mostlytechnic, on Flickr Here's the same unit from above. Note that the pulleys on each side have the frictionless pins opposite each other. Seems like a good way to drive reciprocating motion like legs or arms or something. And there's strangely a big hole up the middle. Building the Dinosaur, 4 Building the Dinosaur, 4 by mostlytechnic, on Flickr Now more of the internals are coming together. The front motor drives (or at least it will shortly, when another rubber band is added) the worm gear on the side. There's lots of pins on the sides ready for the vertical reinforcing beams to be added as well. Building the Dinosaur, 4b Building the Dinosaur, 4b by mostlytechnic, on Flickr The back - the motor goes through a couple stages to drive the pulleys on the sides. Building the Dinosaur, 5 Building the Dinosaur, 5 by mostlytechnic, on Flickr There are so many pivot points here it's crazy. So much flexibility, this has to be the tail. Building the Dinosaur, 6 Building the Dinosaur, 6 by mostlytechnic, on Flickr The dino is starting to take shape. The tail is attached to the back of the motor unit, and several flex cables link it together. There's one up the top center for support, and a pair on the sides that hook to the pulleys to make the tail sway back and forth. Building the Dinosaur, 7 Building the Dinosaur, 7 by mostlytechnic, on Flickr A lot of black beams have been added. Too bad the slope bricks at the back of the body have stickers on them... with all the pieces in this set you'd think they could have avoided reusing stickered pieces like this. On the technical side, there's more pulleys added up front and additional flex cables on the sides. These flex cables route through the dark grey tubes so they can bend but stay in place. Building the Dinosaur, 8 Building the Dinosaur, 8 by mostlytechnic, on Flickr It's almost alive... there's cute little T-Rex arms with "claws" connected to the side pulleys so they move. A short flex cable hooks to the back of the neck for support, while being connected to a cam in the center of the body so it pulls. Building the Dinosaur, 9 Building the Dinosaur, 9 by mostlytechnic, on Flickr A head. And yes, I realize I mounted the lower jaw upside down. It'll be fixed for the next image, I promise. Didn't seem worth taking the set partially back apart to remake this photo though. So, the side flex cables hook to the balls on the sides of the steering arm to rock the head side to side. Another flex cable hooks to the back of the head to hold it up and make it open and close as it moves. Building the Dinosaur, 10 Building the Dinosaur, 10 by mostlytechnic, on Flickr Nearly done. The hole in the center (remember that, from many steps ago?) goes onto the stand and there's a single axle through the body for support. The vertical axles do connect to the body, and the power from the body motors hooks to the control panel. The whole thing is pretty well balanced on that pivot axle, so it's easy for those vertical axles to tilt the whole body up and down. Building the Dinosaur, 11 Building the Dinosaur, 11 by mostlytechnic, on Flickr A leg. With so many pivots and angles and beams it'd take an engineering degree to design. Building the Dinosaur, 12 Building the Dinosaur, 12 by mostlytechnic, on Flickr Two of those legs, mirror images of each other, attach to the body and the base. They look great, even though they don't actually support any weight. It's a great way to hide the light grey support stand though. The Complete Beast The Complete Beast by mostlytechnic, on Flickr From the front, the dino looks properly menacing with the teeth and eyes. The Rare Pieces The rare pieces by mostlytechnic, on Flickr So, this is a prime example of Lego being financially unsound back in the day. This big red plate - there's 4 f them in the set (well, 2 left and 2 right). This wing-like piece was only in this set and one other, years later, in red. It came in black/white/grey at the same time, so the only reason it was used in red for this set was to make the helicopter platform stand out. Why not use simpler, common red pieces instead? Second piece is a cute white coil. It is used to bundle wires together. It only came in this set, the earlier 8082 Multi-Control set, and a handful of educational sets. It's a great part, but not necessary. Finally, this steering part on the right. It's used in the neck of the dinosaur, but a similar effect could have been done with axle connectors and liftarms, just not as neatly. This was the ONLY set to ever include it in black, and it only ever appeared in white in a late 80s Technic car. There's also 5 flex cables in the set that only appear in this model. The Video A set like this demands video. This is not a static model like many Lego designs - this is motorized and programmable and moving. I made a separate video for each model, so you can see what you want easier. The hovercraft - cool idea and mechanically well done, but not nearly as impressive as the other two. Plus I just can't get over the short cable length. The helicopter - awesome! There's clever design here with having some of the motors inside the chopper and one in the base. The balance and friction pins let it stay wherever you put it vertically, and the motion is just cool. It's a nice design aesthetically and very playable. The dinosaur - in my opinion, the star of the show. It might not be as playable as the helicopter, but the motion is just so unique and well done. It's impressive to see a toy like Lego, rigid and bricklike and normally used to make simple mechanical machines, be so fluid and natural in its motion. The use of flex cables is vital to making this work and it's done brilliantly. (Note though in the video that my set is second hand and old. It was obviously left built as a dino for a long time, since the flex cables have a permanent bend to them. This makes the tail movement not as smooth as it should be.) This is hands-down the version I'll keep on display - though I'd love to have a second set to have the helicopter on display as well! Hm, I wonder if I get just a control box, build my own stand, and mount the Sopwith Camel on it and motorize it... that'd make a sweet combo too! (all videos can be seen full 1080p HD on YouTube) The Conclusion: GET THIS SET if you love Technic. It's such a change from the trucks and construction equipment that we're used to. The build style is so different (for you youngsters who only know the studless era of Technic) and the designs are expertly done. I actually though skipped one whole feature of this set - the programability! That control box can save and replay "programs" of button presses, so you can automate your creations. It really was the precursor to the RCX and NXT systems, although there's no logic in the controller. It simply records your button presses (including timing) and plays them back. Two sequences can be remembered at a time. Frankly, the main use I'd see for that in this set is for display. If I was going to have the dino or helicopter out on display, I'd definitely record a nice set of movements so I could play them back with a quick button press for visitors. The Ratings Value: 10/10 - It was an expensive set in its day, and it's expensive now. However, you get the control box, 3 motors, tons of Technic bricks, and great designs. Design: 10/10 - The design is outstanding. All 3 models are visually spot-on. I personally love this era of Technic where models weren't trying to look cosmetically perfect with lots of panels. It's still instantly recognizable and lets you see the internals. The mechanisms are brilliantly executed and make great use of the part selection AND the control panel. Playability: 9.5/10 - I wanted to give another 10, but those short wires on the hovercraft still bug me. Since no one will play with that model for more than a few minutes before building the other two though, I only took off half a point. Parts: 9/10 - There's tons of bricks and plates, a bundle of electronics, flex cables, and more. However, it's mostly black and grey, so not visually terribly interesting. Overall: 10/10 - The helicopter and dinosaur are simply awesome, some of the best designs ever to come from Lego. I'm glad I spent the money to get this set!