RADIO CONTROLLED CAR KIT MODEL RCC-7K Instruction & Assembly Manual Elenco Electronics, Inc. ® Copyright © 2005, 2001 by Elenco® Electronics, Inc. All rights reserved. Revised 2005 REV-I 753288-I No part of this book shall be reproduced by any means; electronic, photocopying, or otherwise without written permission from the publisher.
PARTS LIST Contact Elenco® Electronics if any parts are missing or damaged. DO NOT contact your place of purchase as they will not be able to help you. CARD 1 - RESISTORS (in Bag 2) Qty. 1 5 1 2 2 2 1 2 2 1 2 Symbol R11 R12, R17, R18, R19, R20 R5 R1, R21 R13, R14 R15, R16 R10 R4, R8 R2, R3 R9 R6, R7 Value 68Ω 5% 1/4W 100Ω 5% 1/4W 200Ω 5% 1/4W 560Ω 5% 1/4W 1kΩ 5% 1/4W 1.5kΩ 5% 1/4W 2.7kΩ 5% 1/4W 3.3kΩ 5% 1/4W 22kΩ 5% 1/4W 200kΩ 5% 1/4W 3.
BAG 3 - SCREWS Qty. 5 4 3 Description Part # Screws 0.4” x 0.1” (10mm x 2.6mm) Screws 0.3” x 0.1” (8mm x 2.6mm), 0.15” head Screws 0.3” x 0.1” (8mm x 2.6mm), 0.2” head BAG 4 - HARDWARE Qty. 2 1 2 1 1 2 1 1 2 1 1 1 1 1 1 1 1 1 1 1 1 1 Rear Springs Front Spring Shock Absorber Springs Rear Rod 0.8” x 0.
INTRODUCTION The RCC-7K is a radio-controlled car that you put together. It has 7 control functions: forward, forward-left, forward-right, backward, backward-left, backward-right, and stop. The remote control operates at a frequency of 27.9MHz. It uses 4 AA batteries and one 9V battery (not included). It takes about 7 hours to build. Assembly of the RCC-7K will prove to be an exciting project and give much satisfaction and personal achievement.
reduce power to the Motor and degrade the receiver’s ability to filter, amplify, and decode commands from the Transmitter. Radio Receiver: (refer to the schematics and block diagram on p.31 as needed) The car antenna collects radio energy and converts it back into electrical energy; the energy here will always be much less than the energy originally applied to the transmitting antenna.
CONSTRUCTION Introduction Assembly of your RCC-7K R/C Car Kit will prove to be an exciting project and give you much satisfaction and personal achievement. If you have experience in soldering and wiring techniques, then you should have no problem with the assembly of this kit. Care must be given to identifying the proper components and in good soldering habits. Above all, take your time and follow these easy step-by-step instructions. Remember, “An ounce of prevention is worth a pound of cure”.
IDENTIFYING CAPACITOR VALUES Capacitors will be identified by their capacitance value in pF (picofarads) or µF (microfarads). Most capacitors will have their actual value printed on them. Some capacitors may have their value printed in the following manner. Second Digit Multiplier First Digit Multiplier Tolerance For the No. 0 1 2 3 Multiply By 1 10 100 1k The above value is 10 x 1,000 = 10,000pF or .
ASSEMBLY INSTRUCTIONS 1 Inspection of Parts: Take a look at each of the parts bags and compare to the Parts List (on pages 1 & 2). Be sure that nothing was damaged during shipment and handling. Contact Elenco® Electronics if you have any problems (phone number is on the back of this manual). 2 Remote Control Transmitter 9V Battery Slot (Alkaline recommended) Note: Screw in tight. Transmitter Antenna Switch Placement Insert the switch onto the posts.
3 Driving Motor (the larger motor; Yellow wire goes to tab next to ⊕ marking in plastic) 0.1µF Capacitor (marked 104): Solder leads to motor tabs, one lead is also soldered to motor shell. You cannot get good connections soldering to the motor shell unless you first file or scrape away a small area of the outer coating. Green Wire Yellow Wire ⊕ NOTE: If you have a problem putting the gear on the shaft of the motor, then gently tap the gear on with a hard object.
4 Rear Wheels Locators NOTE: The next 3 steps will be much easier if you elevate the car about 1” using a small object. Rear Axle: the “grip” near the middle should be toward the left Gear for rear axle: slide on until it is firmly in the “grips” on the axle Hard surface Note: You may want to use the method illustrated above to slide the gear onto the rear axle. Warm the axle and gear with a heat gun or hairdryer, then press the gear on carefully using both thumbs.
5 NOTE: Put some Vaseline or grease into the slots for the rod and some on the teeth of all the gears (motor gear, middle gear, and the rear axle gear). This will make the car go faster. Gear, Middle of rear section Rear Rod Quick Test: All 3 gears should be lined up and turning one of them by hand should also turn the others. Check the alignment of the gears. The middle gear must not be able to slide out of alignment with the other gears.
Screw Used (shown actual size) 6 X2 0.4” x 0.1”, 0.15” head 0.4” x 0.1”, 0.15” head Screws Rear Section Cover NOTE: Make sure that the wires from the ON/OFF switch and the motor run out of the rear section cover through the slots (as shown) without being damaged. Quick Test: Lift the wheels off the ground so they may spin freely. Connect a 1.5V battery across the motor wires with your hands, (+) terminal to green wire. The wheels should spin forward slowly but smoothly.
Bend wires to fit around post. They must NOT be tight (or the steering won’t work), stretch the wire with your fingers to loosen it if necessary. 7 Spring for Steering Centering Steering Alignment Adjustment post is towards front of car front of car (triangular piece will lean against this) Steering Bar Between the Wires After inserting wire on it, melt the top of this post with a soldering iron to keep the spring in place.
Steering Motor 0.01µF Capacitor (marked 103): Solder leads to motor tabs, one lead is also soldered to motor shell. (the smaller motor; Blue wire goes to tab next to ⊕ marking in plastic) 8 You cannot get good connections soldering to the motor shell unless you first file or scrape away a small area of the outer coating. Orange Wire ⊕ ⊕ Side Tab: bend tab back 180O and solder to motor shell Screw Used (shown actual size) X2 Quick Test: Connect a 1.
9 Front Spring Front Wheel Shock Absorbers Post -14-
10 0.3” x 0.1”, 0.15” head Screws Screw Used (shown actual size) X2 0.3” x 0.1”, 0.15” head Front Wheels Section Cover Quick Test: Install 4 fresh AA alkaline batteries in the battery cage, observing their polarity while doing so. Lift the front wheels off the ground so they may spin freely. Touch the steering motor wires to the left-front and left-rear battery contacts with your hands. The front wheels should turn to one side (as the steering motor gear moves along the steering bar).
11 ASSEMBLE THE FOLLOWING COMPONENTS TO THE PC BOARD Review the soldering and parts identification instructions on p.5 at this time. In all of the following steps the components must be installed on the top legend side of the PC board. The board is turned over to solder the component leads. L1 - 9 Turn Inductor (this part has been pre-tuned, you do not need to adjust it). (see Figure A) R13 - 1kΩ 5% 1/4W Res. (brown-black-red-gold) (see Figure B) R14 - 1kΩ 5% 1/4W Res.
12 Figure E Stand resistor on end as shown with the body inside the white circle (if a white circle is present). White Circle (see Figure E) R21 - 560Ω 5% 1/4W Res. (green-blue-brown-gold) R10 - 2.7kΩ 5% 1/4W Res. (red-violet-red-gold) R4 - 3.3kΩ 5% 1/4W Res. (orange-orange-red-gold) R3 - 22kΩ 5% 1/4W Res. R2 - 22kΩ 5% 1/4W Res. (red-red-orange-gold) R3 R1 - 560Ω 5% 1/4W Res. (green-blue-brown-gold) R5 - 200Ω 5% 1/4W Res. (red-black-brown-gold) R6 - 3.9MΩ 5% 1/4W Res. R7 - 3.9MΩ 5% 1/4W Res.
13 (see Figure F) C1 - 10pF (10) Capacitor C10 - 0.01µF (103) Capacitor C2 - 27pF (27) Capacitor C3 - 27pF (27) Capacitor C7 - 0.1µF (104) Capacitor C8 - 500pF (501) Capacitor C4 - 3,300pF (332) Capacitor C9 - 0.01µF (103) Capacitor C11 - 2,200pF (222) Capacitor Figure F Figure G Mount the ceramic or mylar capacitor as shown below. Mount the electrolytic capacitor as shown, noting the polarity as shown.
14 (see Figure H) Q5 - S8550 Transistor Q6 - S8550 Transistor Q8 - S8050 Transistor Q2 - 9014 Transistor Q3 - 9014 Transistor Q7 - S8050 Transistor Q14 - S8050 Transistor Q12 - S8550 Transistor Q9 - 9014 Transistor Q10 - 9014 Transistor Q13 - S8050 Transistor Q11 - S8550 Transistor Q1 - C945 Transistor Inspection: Figure H Mount the transistor with the flat side in the same direction marked on the PC board. 1/8” Double check that you have installed all of your parts in the proper places.
15 TRANSMITTER TESTING If you have an oscilloscope then you may test the remote control transmitter for basic operation. Set the scope for 1V/div vertical scale and 1ms/div horizontal scale. Install a 9V battery in the transmitter if you haven’t already done so. Connect your scope probe to the transmitter antenna (leave the probe ground unconnected), turn on the transmitter, and push the left transmitter lever. You should see a stream of high-frequency bursts at least 1Vpp in amplitude, of either 0.
16 INTERCONNECTIONS & TESTING Vcc Wire Solder the red wire from the ON/OFF switch to this solder pad. BE CAREFUL TO AVOID TOUCHING NEARBY PADS! Red wire from switch Black wire from battery contact Ground Wire Solder the black wire from the battery contact to this solder pad. BE CAREFUL TO AVOID TOUCHING NEARBY PADS! Resistance Tests Remove one or all of the “AA” batteries from the car for these tests.
Battery Tests 17 Install 4 fresh AA alkaline (or rechargeable nickelcadmium) batteries in the battery cage, observing their polarity while doing so. Caution: Do not mix alkaline, standard (carbon-zinc), or rechargeable (nickelcadmium) batteries. Snap in the battery cover to close it. Battery Voltage: Using a multimeter set to DC volts, measure between the front-left and front-right battery contacts. You should measure about 6V. Idle Current: Set the ON/OFF switch to OFF. Set your multimeter to DC amps.
18 Steering Voltage Tests Antenna solder pad Activate the transmitter for left/right while measuring the voltage at pins 6 & 7 on the SCRX2BC IC. (Note: on some models the steering lever only works if you are also pressing the forwards/backwards lever). Notes: You may need to touch the antenna on the remote control unit to the antenna solder pad (next to C1), since the car’s antenna is not attached yet.
19 Driving Motor Tests Solder the yellow wire from the driving motor AND one of the wires from the light bulb to the Q6-Q8 junction on the PCB. BE CAREFUL TO AVOID ALSO TOUCHING NEARBY PADS.. Solder the green wire from the driving motor AND the other wire from the light bulb to the Q5-Q7 junction on the PCB. BE CAREFUL TO AVOID ALSO TOUCHING NEARBY PADS. Yellow wire from driving motor Light Bulb Green wire from driving motor Elevate the rear of the car so that the rear wheels may spin freely.
20 Light Bulb Cover Light Bulb NOTE: Tape the light bulb wires to the inside of the top frame so that the light bulb stays above it. Top Frame Screw Used (shown actual size) X1 0.3” x 0.1”, 0.2” head Screw -25- 0.3” x 0.1”, 0.
21 Receiver Alignment (highly recommended) Although tunable inductor L1 has been pre-aligned, you may adjust it for optimum performance. You need a very small screwdriver for this. The Car Antenna must be screwed together with the PCB and bottom frame as shown below, to make a good connection. Flip the ON/OFF switches to on. Activate the transmitter and move it away from the car. (This is difficult to do by yourself unless you use a rubber band to keep the transmitter activated.
22 Tab Tab Tabs Rear Springs 23 Decorative Decals: Place these on now, using your RCC-7K box as a guide. Note that some models may not use all of the stickers provided. 24 Steering Alignment: Your car is ready for use. If it does not go straight when you release the right control lever, then adjust the steering alignment on the bottom front of the car until it works properly. Front Steering Alignment Adjustment You have now completed the assembly of the RCC-7K Radio Controlled Car.
HOW TO USE IT Place the car in a flat, open area, turn the ON/OFF switches in the car and Remote Control to ON, and extend the antenna on the Remote Control. The LEFT lever on the Remote Control: Push forward (or forward-right) to make the RCC-7K go forward. Push backward to make the RCC-7K go backward. Push to center or let go to stop. The RIGHT lever on the Remote Control: Push left to make the RCC-7K turn left. Push right to make the RCC-7K turn right. Push to center or let go to go straight.
TROUBLESHOOTING GUIDE Symptom: Car does not go in a straight line when you release the right control lever. • Adjust the front wheels alignment control on the underside of the Bottom Frame, as you did in assembly step 24. Symptom: Car doesn’t work at all. • Make sure that the batteries in both the car and the Remote Control Transmitter are strong and that they are installed with the positive and negative terminals positioned properly.
Symptom: Car does not go forwards/backwards or does so erratically. • Be sure all the car batteries are strong and all your wires make strong connections. • Make sure the wheels are all free of thread, lint, or hair and that the black rubber on the wheels is not coming off. • If the driving motor gears are slipping, tighten the screws for the rear section cover and top cover. • Retune inductor T1 as per the Receiver Alignment on page 26. • Spin the rear wheels with your hands.
SCHEMATICS AND BLOCK DIAGRAM TRANSMITTER SCHEMATIC L T2 X Y PC VDD EC SCTX2BC R T1 VSS B F TB ENC RECEIVER SCHEMATIC (3.1V) (6V) YELLOW (1.1V) GREEN SCREW (2.0V) DRIVING CIRCUIT (3.0V) 10pF (1.8V) RED (1.1V) (1.8V) (0.8V) V3 V1 VDD TB V2 F B LX_ R L RX_ SCRX2BC (0.25V) V4 VSS DI X Y (1.7V) (1.7V) (1.7V) ORANGE (0.
BLOCK DIAGRAM 27.
QUIZ 1. The antenna in the Remote Control Transmitter converts electrical energy into . . . . . A - radio energy. B - mechanical energy. C - geothermal energy. D - nuclear energy. 2. The commands to be sent from the Remote Control Transmitter are encoded onto a sequence of electrical pulses by changing . . . . . A - the spacing between the pulses. B - the duty cycle of the pulses. C - the number of pulses in the sequence. D - the amplitude of the pulses. 3.
Here are some other exciting projects from Elenco® you can build. EDUCATIONAL KITS Motion Detector Kit Stereo Cassette Player Kit with training course Model AK-510 Model AK-200 Simple and fun to build, compact, portable and adds safety to your home or office. Learn the basics of motion detector technology while building this motion detector kit that uses a pyroelectric infrared sensor. Comes complete with all parts, PC board, case, schematic and extensive training manual. Requires one (1) 9V battery.
Elenco® Electronics, Inc. 150 Carpenter Avenue Wheeling, IL 60090 (847) 541-3800 Fax: (847) 520-0085 Website: www.elenco.com E-mail: elenco@elenco.
