EK002 Atari Punk Robot

Part.no: 41017270

The kit in front of you is called a Stepped Tone Generator or Sound Synthesizer. It was first published by electronics legend Forrest Mims III and later became popular in updated versions under the name Atari Punk Console.

This version is designed in the shape of a robot with a speaker, light sensors that control the sound, and LEDs that pulse and illuminate.

The circuit is built around two 555 timers. The first timer is configured as an oscillator that generates a continuous tone. The second timer functions as a pulse generator and divides the frequency from the oscillator. Together, the two timer circuits form a simple but surprisingly complex melody generator that responds to light.

When fully assembled, the robot will play melodies as soon as it is powered. Depending on the amount of light falling on the sensors, the tones will become higher with more light and lower with less light.

It is possible to "play" melodies by moving your hands in front of the sensors, flashing lights, or by moving the entire robot. Experiment with different light sources.

The sensors can be replaced with other components that have a resistive output to provide alternative ways of controlling the sound. Suitable options include NTC resistors, temperature sensors, humidity sensors, or standard potentiometers. Best results are achieved with sensors that have a resistance range of approximately 5kohm to 1Mohm.

Component list

Name	Marking	Qty.	Part.no.
Robot PCB		1
Dual timer IC	NE556N	1	40350556
Axial elyt capacitor	10uF	2	40525010
Ceramic capacitor	10nF (103)	1	41011998
Ceramic capacitor	100nF (104)	1	41015538
Resistor 10k		2	40811410
Resistor 1k		1	40811310
Photoresistor (LDR)		2	40850001
LEDs 5mm	Assorted colors	3	LED 5mm
Speaker 23mm		1	41017231
Slide switch		1	41011898
Battery holder 9V		1	41000885
Screw M2 8mm		1	41013913
Hex nut M2		1	41013902

Assembly guide

Tools

The following tools are required for assembly:

Solder station or solder pen (30W minimum)
Lead-free solder wire
Side cutter (for trimming component leads)

Recommended additional tools:

Wire stripper (for stripping the battery holder wires)
Needle-nose pliers (for bending component leads)
PCB holder or helping-hand
Multimeter (for troubleshooting and component identification)
Solder sucker (for desoldering components)

Step by step assembly guide

The PCB on which the components are to be mounted is supplied as a larger panel with sections that must be separated before assembly.

Start by carefully breaking off the left and right sides. Continue by separating the legs, arms, and the support tabs.

Collect the parts and set the legs and arms aside for now. The support tabs can be discarded as they no longer serve any purpose.

The serrated edges where the supports were attached can be trimmed or filed down using a knife, side cutters, file, or sandpaper. This is not strictly necessary, but it provides a cleaner final result.

The first component to be mounted is the timer IC (LM556). It is important that it is installed with the correct orientation. If it is mounted incorrectly, it will be damaged immediately. The semicircular marking on one short side of the IC must be aligned in the same direction as the symbol on the PCB.

The leads of the IC must be bent slightly for mounting. The optimal angle for the leads is 90 degrees relative to the IC body.

The easiest way to bend the leads is to place the IC flat against the table and carefully but firmly press and tilt the entire component so that all leads are bent simultaneously. This step is repeated twice, once for each row.

With the leads bent as shown above, the IC should fit easily into the PCB. With the IC in place, carefully turn the board over and place it on the table with the underside facing you. Solder all the leads.

The spacing between the leads is very small, so take care to avoid bridging adjacent pins with solder.

Once the IC is in place, the next step is to mount the resistors and capacitors.

The leads of the resistors and electrolytic capacitors must be bent at right angles to fit the PCB. The ceramic capacitors have both leads oriented in the same direction and can be inserted as they are.

Place one component at a time. Before placing the next component, bend both leads slightly outward to prevent it from falling out.

Resistors and ceramic capacitors are not polarized and can be mounted in any orientation. Electrolytic capacitors, however, must be installed with the correct polarity. Arrows with minus signs indicate the negative terminal, which should be inserted into the round hole. The other lead should be inserted into the square hole.

Perform a final inspection once all components are mounted. Verify that they are placed in the correct positions and oriented correctly. If everything is correct, proceed with soldering.

Make sure not to use excessive solder. Heat the joint until the solder flows properly onto both the component lead and the PCB.

It is easy to accidentally bridge two connections during soldering. It is important to correct this before continuing the assembly.

To fix a bridge, melt the solder forming the bridge and quickly draw the tip straight through it. This may need to be repeated several times until the bridge is removed.

Once all connections are soldered, trim the component leads. Cut as close to the PCB as possible without cutting into the solder joint.

The next component to be mounted is the power switch.

The switch should be mounted on the underside of the PCB. To prevent it from falling out during soldering, the board can be placed flat on the table so that the PCB helps hold it in position. It is also possible to solder it from the top side so that it holds itself in place.

The next step is to mount the LEDs that form the robot’s eyes and nose. LEDs are also polarized and must be installed with the correct orientation.

On this PCB, all the longer leads of the LEDs should be facing inward, toward each other. The orientation can also be identified by the shape of the holes in the PCB. The long leads should be placed in the round holes and the short leads in the square holes.

Solder the LEDs in the same way as the resistors and capacitors. Place one LED at a time, bend the leads outward, double-check the orientation, and solder both leads.

If the leads are in the way during soldering, they can be trimmed slightly shorter. Cut off the remaining length once they are soldered.

LEDs can be somewhat difficult to mount straight and flush against the PCB. If they end up slightly misaligned, this can be corrected by pressing the LED with one hand while alternately reheating the solder joints. Continue until the LED is properly aligned.

The LED connections are very close to each other, so it is especially important to watch for solder bridges in this step.

The next component to be mounted is the speaker. Speakers are also polarized, but in this kit it does not matter which orientation is used.

The leads on the speaker are short and thick, which can make them difficult to bend by hand. Use pliers if necessary.

The final components to be mounted are the antennas, or light sensors. They are not polarized.

The sensors can be mounted close to the PCB like the other components. For a more refined appearance, try to mount them with their full lead length intact. This allows them to be bent and shaped as desired.

The robot is powered by a 9V battery. The battery is securely housed in the robot’s backpack, the battery holder.

The wires can be soldered as they are, or trimmed shorter if desired. If trimmed, cut them to approximately 30mm in length and strip about 1-2mm from the ends.

The red wire should be inserted into the hole marked “+” and the black wire into the hole marked “-”. Once both wires are soldered, bend them outward so they are not pinched between the holder and the PCB.

Since the speaker is positioned close to the mounting holes for the battery holder, it can only be secured with one screw, which is acceptable. It will still be stable.

Fasten the holder using the supplied screw and nut. The screw should be inserted from the battery holder side, with the nut on the opposite side.

If the wires protrude on the front side after soldering, they can be trimmed in the same way as the leads of the other components.

This is a good time to use a multimeter to check that there are no short circuits or broken connections.

To check for short circuits, measure the resistance between V+ and V- (the red and black wires from the battery holder). The resistance should be approximately 7.5kohm.

If the resistance is lower, there is a short circuit somewhere on the board. If the resistance is higher, a solder joint has likely been missed. The LEDs can be tested using the diode test function on the multimeter.

If everything appears correct, insert the battery and power up the circuit. If it sounds terrible and the LEDs are lit, it is working and you can proceed to the next step.

Now comes the fun, three-dimensional part of the assembly.

Take out the separated PCB parts. Two arms and two legs are required.

The parts can be mounted in any order, but in this guide the legs are installed first.

Start by placing a leg into the slot under the battery holder. The beveled side should face the front, and the flat side should fit under the battery holder.

Make sure the solder pads are facing outward on the side, otherwise it will be very difficult to access them for soldering.

Place the robot on its side so that the leg stays in position.

Solder along the entire length of the leg. Ensure that the solder forms a smooth fillet between the two PCBs. Be careful not to pull the leg out of position when moving the soldering iron across the joint.

Repeat the process for the other leg and both arms.

The robot should now be fully assembled and ready for operation.

The LEDs should light up and the speaker should produce sound.

If everything is functioning correctly, the frequency of the tones will increase in bright light and decrease in darkness.

Troubleshooting

The robot does nothing at all!
- Inspect and resolder all the solder joints. The most common error when soldering is a missed or bridged solder joint.
- Check that all components are in the right place and orientation.
- Measure the battery voltage. If it's lower than 8.5V, replace the battery.
- Make sure the switch is in the "ON" position.
The robot only makes a high frequency whine and nothing else!
- The antenna leads are probably shorted. Separate the leads and try again.
The robot makes sounds, but the LEDs are not working!
- Make sure the LEDs are mounted in the correct orientation.
- Maybe the robot is not getting enough light. Try shining a light on the sensors.
I can't get the arms or legs to stick to the body!
- The arms and legs are the most difficult parts to solder in this kit. They require more heat and can take up to a minute to reach soldering temperature. Be patient!
The robot is unstable and falls over easily!
- Make sure the legs are mounted straight and in the same height. The legs can be evened out by melting the solder between the leg and body and adjust while the robot is standing up.
I've checked all the steps in the troubleshooting guide but it still doesn't work!
- Please contact Electrokit customer service for further assistance.