How many pieces are in the Robo Technology Set (Serial Cable)?

Robo Technology Set (Serial Cable) contains 221 pieces.

When was the Robo Technology Set (Serial Cable) released?

Robo Technology Set (Serial Cable) was released in 2003.

🏛 RCX

Set #9785

Robo Technology Set (Serial Cable)

The Robo Technology Set (Serial Cable) is a fascinating glimpse into LEGO's early forays into robotics.

Before you buy

Who it's for: Intermediate build Enthusiasts interested in LEGO robotics and programming, educators looking for hands-on learning tools
Build: 221 pieces · about 4.5 hours Build time is an estimate.
Availability: Likely retired

★★★☆☆ 3.8 AI-generated review score, not a customer rating

Fans appreciate this set as a foundational introduction to LEGO robotics, but some find the programming interface outdated and the building experience simple. The limited sensor options compared to newer Mindstorms sets are a common criticism.

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📝 Our Take

AI-assisted editorial summary, grounded in our LEGO database and public community discussions. How we use AI

The Robo Technology Set (Serial Cable) is a fascinating glimpse into LEGO's early forays into robotics. Released in 2003, this set provides the fundamental building blocks for creating programmable robots using the RCX brick and Technic parts. It's a great way to explore the intersection of LEGO and computer programming.

This set is perfect for LEGO enthusiasts interested in robotics and programming. The building experience is relatively straightforward, focusing on functionality over complex aesthetics. It's a fantastic educational tool for introducing basic robotics concepts.

Skip this if you're looking for visually stunning display models or advanced building techniques. This set prioritizes functionality and programming over intricate design. Consider more recent LEGO Mindstorms sets for more advanced robotics features and a wider range of sensors.

✨ New

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What are the key differences between this set and newer LEGO Mindstorms sets? How can I use this set to teach basic robotics concepts? What is the best way to store and maintain the RCX brick to ensure its longevity? How does the value of this set compare to other early LEGO robotics sets?

🧱 Building Experience

AI-assisted build estimate, grounded in our LEGO database and public community discussions. How we use AI

🧩

221

Pieces

⏱

4.5h

Estimated Build Time

📊

Intermediate

Difficulty

Build Highlights:

Learning the basics of programming LEGO robots
Understanding gear ratios and mechanical movements
Experimenting with sensors and motor control
Creating custom robot programs

📈 Investment Analysis

AI-assisted investment analysis, grounded in our LEGO database and public community discussions. How we use AI

Not enough price history for a trend

Investment Grade

⏳ Retired

The Robo Technology Set (Serial Cable) holds moderate investment potential. As an early Mindstorms-adjacent set, it appeals to collectors interested in the history of LEGO robotics. The relatively low piece count and specialized nature of the RCX system limit its mass appeal, but its rarity and historical significance could drive value over time. Keeping the set complete with the serial cable and software is crucial for maximizing its investment potential. The condition of the RCX brick is also a key factor.

Not Financial Advice: Content is for educational purposes only. Past performance doesn't guarantee future results. Full disclaimer

⚖ Compare Similar Sets

Mindstorms Robotics Invention System 2.0

The Robo Technology Set (Serial Cable) is a foundational set in LEGO robotics, but it lacks the advanced sensors and capabilities of modern Mindstorms sets. While newer sets like the LEGO MINDSTORMS Robot Inventor (51515-1) offer more sophisticated programming and building options, this set provides a unique historical perspective on LEGO robotics. Collectors interested in the evolution of LEGO technology may prefer this set, while those seeking advanced functionality should opt for newer Mindstorms offerings.

📦 Parts Inventory

Piece count: 221
Parts cataloged in this inventory: 67 unique parts, 221 pieces

Missing a piece? Check this set piece by piece, with look-alike colors flagged and element IDs for replacements.

Plate Round 2 x 2...

Part #: 2654 2× Black

Technic Pin with ...

Part #: 2780 12× Black

Technic Wedge Bel...

Part #: 2815 2× Black

Tyre 81.6 x 15 Mo...

Part #: 2902 2× Black

Wheel 61.6 x 13.6...

Part #: 2903 2× White

Sensor, Light wit...

Part #: 2982c01 1× Blue

Brick 2 x 4

Part #: 3001 6× Red

Brick 2 x 2

Part #: 3003 6× Yellow

Dome Hemisphere 4...

Part #: 30208 2× Trans-Neon Green

Part #: 32001 4× Blue

Technic Pin 3/4

Part #: 32002 8× Dark Gray

Technic Axle Conn...

Part #: 32039 2× Light Gray

Technic Axle 2 No...

Part #: 32062 4× Black

Technic Brick 1 x...

Part #: 32064b 4× Green

Technic Axle 5

Part #: 32073 2× Light Gray

Technic Bush 1/2 ...

Part #: 32123a 8× Light Gray

Technic Beam 3 x ...

Part #: 32250 2× Blue

Plate 1 x 8

Part #: 3460 2× Blue

Wheel with Split ...

Part #: 3482 4× Yellow

Tyre Offset Tread...

Part #: 3483 2× Black

Tyre 43 x 17

Part #: 3634 2× Black

Technic Gear 8 Tooth

Part #: 3647 3× Light Gray

Technic Gear 24 T...

Part #: 3648b 2× Red

Technic Gear 40 T...

Part #: 3649 2× Green

Technic Pin witho...

Part #: 3673 12× Light Gray

Part #: 3703 2× Black

Technic Axle 4

Part #: 3705 2× Black

Technic Axle 6

Part #: 3706 2× Black

Technic Axle 8

Part #: 3707 2× Black

Technic Axle 12

Part #: 3708 2× Black

Technic Plate 2 x...

Part #: 3709 4× Yellow

Technic Bush

Part #: 3713 20× Light Gray

Technic Axle 10

Part #: 3737 2× Black

Technic Plate 2 x...

Part #: 3738 4× Yellow

Technic Axle Pin ...

Part #: 3749 8× Tan

Plate 2 x 10

Part #: 3832 2× Light Gray

Part #: 3901 1× Brown

Bracket 2 x 2 - 2...

Part #: 3956 2× Blue

Technic Wedge Bel...

Part #: 4185 2× Yellow

Technic Pin 1/2 w...

Part #: 4274 4× Light Gray

Technic Axle 3

Part #: 4519 2× Light Gray

Wire with Brick 2...

Part #: 5306bc020 3× Black

Wire with Brick 2...

Part #: 5306bc036 3× Black

Light Brick 1 x 2...

Part #: 6035 1× White

Hair Ponytail

Part #: 6093 1× Black

Technic Axle and ...

Part #: 6536 2× Light Gray

Technic Axle Conn...

Part #: 6538b 2× Light Gray

Technic Axle 1.5 ...

Part #: 6553 4× Light Gray

Technic Axle 3 wi...

Part #: 6587 2× Dark Gray

Motor, 9V Mini [O...

Part #: 71427c01 2× Light Gray

Cable, Serial, fo...

Part #: 71793 1× Light Gray

Transmitter Tower...

Part #: 76091 1× Dark Gray

Hose, Ribbed 7mm ...

Part #: 78c12 2× Purple

Technic Rubber Be...

Part #: 85544 4× Blue

Sensor, Touch

Part #: 879 2× Light Gray

Hub, RCX 2.0, No ...

Part #: 884c 1× Yellow

Hips and Blue Legs

Part #: 970c28 1× Blue

Torso, White Arms...

Part #: 973c27h01 1× White

🧱 Playmat / Test Ma...

Part #: 45533 1× [No Color/Any Color]

🧱 Storage Bin Lid, ...

Part #: 71082 1× Trans-Clear

🧱 Storage Bin, Dact...

Part #: upn0038 1× Bright Green

This set features a variety of Technic pins and bushings useful for building functional models. The abundance of Light Gray Technic Bushes and Black Technic Pins makes it a good source for basic Technic elements.