Print PDF
Favorite
Email
Step 13Testing Part 1
Now we are going to take a moment to check the work we've done so far. The test point wires we made in the previous section will help this go by quickly.
If you have a way of securing one of your multimeter probes, such as a hook probe or alligator clip, go ahead and attach it to the VCC TEST point. Otherwise, you will require both hands for this testing.
First we test all 15 pull up resistors. Set your multimeter to a resistance setting greater than 5K Ohms ; on mine, the setting is 20K. With one probe on the VCC TEST point, check each on of the IC socket pins colored red in the image below. That would be pins 1, 6, 15, 16, 17, 19, 20, 21, 22, 27, 28, 29, 30, 37, and 38 . At each point, the resistance should show a value near 4.7K Ohms. The exact value isn't of much important, as long as it is more than 3K Ohms, and less than 6K Ohms. Each one of these you test verifies the soldering on the IC socket at that pin, as well as both pins of the resistor itself. If the test shows infinite resistance, one of those three solder points is cold, somehow disconnected, or your multimeter's resistance(Ohm) setting is less than 4.7k . Fix it before continuing. If any of them show almost 0 resistance, then either the resistance setting on your multimeter is way too high, or you have accidentally shorted that line to VCC before the resistor; check and redo any messy soldering points, making sure not to accidentally short against another pin or a via.
Congratulations, with a simple test, you just verified 45 different soldering points in less than a minute.
Next we will test the yellow points shown on the PCB. Remove the probe on the VCC TEST point. We will need it elsewhere. Set your multimeter to a setting greater than 1 Mega Ohm; on mine, the setting is 2M Ohm. Place one probe on each of the yellow pins. The resistance should read roughly 1 Mega Ohm. If so, you have successfully tested the soldering on those two IC socket pins, as well as both pins on the 1M resistor. If it fails, verify your multimeter is set greater than 1M Ohm, and check those for solder points.
Next, set your multimeter to the lowest setting great than 22 Ohms; on mine, that is 200 Ohms. Place a probe on each of the purple IC socket pins in the picture below. Resistance should read roughly 22 Ohm. If it fails, check the solder points of the purple IC pins, and the solder points of the left-most '22' resistor.
Lastly, keep your multimeter on the lowest setting great than 22 Ohms; on mine, that is 200 Ohms. Place a probe on each of the blue IC socket pins in the picture below. Resistance should read roughly 22 Ohm. If it fails, check the solder points of the blue IC pins, and the solder points of the right-most '22' resistor.
Congratulations, you just verified 59 different soldering points. Let's continue.
If you have a way of securing one of your multimeter probes, such as a hook probe or alligator clip, go ahead and attach it to the VCC TEST point. Otherwise, you will require both hands for this testing.
First we test all 15 pull up resistors. Set your multimeter to a resistance setting greater than 5K Ohms ; on mine, the setting is 20K. With one probe on the VCC TEST point, check each on of the IC socket pins colored red in the image below. That would be pins 1, 6, 15, 16, 17, 19, 20, 21, 22, 27, 28, 29, 30, 37, and 38 . At each point, the resistance should show a value near 4.7K Ohms. The exact value isn't of much important, as long as it is more than 3K Ohms, and less than 6K Ohms. Each one of these you test verifies the soldering on the IC socket at that pin, as well as both pins of the resistor itself. If the test shows infinite resistance, one of those three solder points is cold, somehow disconnected, or your multimeter's resistance(Ohm) setting is less than 4.7k . Fix it before continuing. If any of them show almost 0 resistance, then either the resistance setting on your multimeter is way too high, or you have accidentally shorted that line to VCC before the resistor; check and redo any messy soldering points, making sure not to accidentally short against another pin or a via.
Congratulations, with a simple test, you just verified 45 different soldering points in less than a minute.
Next we will test the yellow points shown on the PCB. Remove the probe on the VCC TEST point. We will need it elsewhere. Set your multimeter to a setting greater than 1 Mega Ohm; on mine, the setting is 2M Ohm. Place one probe on each of the yellow pins. The resistance should read roughly 1 Mega Ohm. If so, you have successfully tested the soldering on those two IC socket pins, as well as both pins on the 1M resistor. If it fails, verify your multimeter is set greater than 1M Ohm, and check those for solder points.
Next, set your multimeter to the lowest setting great than 22 Ohms; on mine, that is 200 Ohms. Place a probe on each of the purple IC socket pins in the picture below. Resistance should read roughly 22 Ohm. If it fails, check the solder points of the purple IC pins, and the solder points of the left-most '22' resistor.
Lastly, keep your multimeter on the lowest setting great than 22 Ohms; on mine, that is 200 Ohms. Place a probe on each of the blue IC socket pins in the picture below. Resistance should read roughly 22 Ohm. If it fails, check the solder points of the blue IC pins, and the solder points of the right-most '22' resistor.
Congratulations, you just verified 59 different soldering points. Let's continue.
| « Previous Step | Download PDFView All Steps | Next Step » |
 |
Add Comment
|
