04 May 2010, 07:31
An electrical engineer friend and I made our first attempt to power up the 25 chip P1 module yesterday. Here's a description of that attempt. Bear in mind that I'm not an electrical engineer (I'm a software guy), so please excuse me if my terminology is not 100% right. Hopefully it's close enough to get the idea across.
To start with, we used the following equipment:
(1) a voltage and current limiting power supply
(2) some tiny micro probes to connect directly to the module
(3) a digital multimeter in between the power supply and probes to measure the actual current draw
We tested the connectivity of the battery holders at the back of the module and found that the bottom one had a broken connection, which explains why it didn't light up when batteries were inserted. After connecting directly to the module, we found that the multimeter was reading 10 milliamps (its lowest reading). That seemed like a good sign since the current draw was neither too high, which would indicate a short, or zero, which would indicate a break in the circuit. We then raised the current limit in 10 milliamp increments until we got reached a maximum of 200 milliamps (this was the clamp on the power supply rather than the actual current draw, which we still need to determine). At that point, we found that activating the main reed switch caused the display to illuminate, showing:
1:01
It's alive!
I thought that the display would be composed of solid segments but it appeared to be composed of tiny dots instead! Also, it was blinking at a steady 10 Hz or so rather than staying constantly illuminated, which may possibly indicate a problem or perhaps may indicate that we're using improper power supply settings. After about 30 seconds, the probes accidentally disconnected when we bumped the module while moving the setting magnet in and out. Unfortunately, we were so mesmerized by the glowing digits that we didn't get a picture of the display or get a reading of the current draw from the multimeter. Doh!
We then tried to repeat the procedure, but had a difficult time getting the tiny probes reconnected. After getting the probes reconnected, we got the module to draw 10 milliamps again, but couldn't get the display to activate again. I hope we didn't break something. The current draw never went above 250 milliamps and the module still consistently draws 10 milliamps. We decided to put it away and think about it for awhile. For the next attempt, we need to gather a little more information and some additional equipment (like an oscilloscope and a more sensitive multimeter).
So, that's encouraging. The module is not 100% working, but it's also not dead either. It appears that the IC and even the clock seem to be at least partially working. Perhaps it can be coaxed back to life. Hopefully, photos of the illumated module will be forthcoming in the not too distant future.
To be continued...
Power Supply connected to Module (through a Multimeter):
Probes Connected to Module:
Closeup of Probes:
Tip of Probe in Open Position:
To start with, we used the following equipment:
(1) a voltage and current limiting power supply
(2) some tiny micro probes to connect directly to the module
(3) a digital multimeter in between the power supply and probes to measure the actual current draw
We tested the connectivity of the battery holders at the back of the module and found that the bottom one had a broken connection, which explains why it didn't light up when batteries were inserted. After connecting directly to the module, we found that the multimeter was reading 10 milliamps (its lowest reading). That seemed like a good sign since the current draw was neither too high, which would indicate a short, or zero, which would indicate a break in the circuit. We then raised the current limit in 10 milliamp increments until we got reached a maximum of 200 milliamps (this was the clamp on the power supply rather than the actual current draw, which we still need to determine). At that point, we found that activating the main reed switch caused the display to illuminate, showing:
1:01
It's alive!
I thought that the display would be composed of solid segments but it appeared to be composed of tiny dots instead! Also, it was blinking at a steady 10 Hz or so rather than staying constantly illuminated, which may possibly indicate a problem or perhaps may indicate that we're using improper power supply settings. After about 30 seconds, the probes accidentally disconnected when we bumped the module while moving the setting magnet in and out. Unfortunately, we were so mesmerized by the glowing digits that we didn't get a picture of the display or get a reading of the current draw from the multimeter. Doh!
We then tried to repeat the procedure, but had a difficult time getting the tiny probes reconnected. After getting the probes reconnected, we got the module to draw 10 milliamps again, but couldn't get the display to activate again. I hope we didn't break something. The current draw never went above 250 milliamps and the module still consistently draws 10 milliamps. We decided to put it away and think about it for awhile. For the next attempt, we need to gather a little more information and some additional equipment (like an oscilloscope and a more sensitive multimeter).
So, that's encouraging. The module is not 100% working, but it's also not dead either. It appears that the IC and even the clock seem to be at least partially working. Perhaps it can be coaxed back to life. Hopefully, photos of the illumated module will be forthcoming in the not too distant future.
To be continued...
Power Supply connected to Module (through a Multimeter):
Probes Connected to Module:
Closeup of Probes:
Tip of Probe in Open Position:
