Hi all, first post here
I 've been reading on electronics the last month (ARRL, Platt and the textbooks here) and I was about to try the " relay oscilator" experiment tutorial (Platt 2nd chapter), when all strange things happened one after the other...
1) I had an old DC 3amp power supply adjustable for 3 to 12volts. When it didn't turned on the relay, i checked volts out and it read 17 volts! Then I turn the volt knob to 9V and it still reads 17 volts. I turn off the supply switch and still 17 volts, verified with two multimeters. Last, I unplugged it from the wall outlet and the volts wouldn't go. Probably a capacitor malfunction but do these symptoms make any sense? (e.g typical indication that the supply or the volt knob is dead)
2)So I thoutgh lets see if the relay works with a 9V alcaline battery (the relay is a DSY2Y-S212L and is supposed to work at 12V). Didn't work, and when i checked the battery voltage it was 7.5V and counted down at a pace of 0.05V/second. I stopped at 6.9V and checked with another multimeter and it was 7.5V steady. Then I connected both multimeters and they both showed a fall 0.05V/second! Maybe the first multimeter draws some current while measuring voltage, but again does it make any sense? Is this any indication of the multimeter quality?
I 've been reading on electronics the last month (ARRL, Platt and the textbooks here) and I was about to try the " relay oscilator" experiment tutorial (Platt 2nd chapter), when all strange things happened one after the other...
1) I had an old DC 3amp power supply adjustable for 3 to 12volts. When it didn't turned on the relay, i checked volts out and it read 17 volts! Then I turn the volt knob to 9V and it still reads 17 volts. I turn off the supply switch and still 17 volts, verified with two multimeters. Last, I unplugged it from the wall outlet and the volts wouldn't go. Probably a capacitor malfunction but do these symptoms make any sense? (e.g typical indication that the supply or the volt knob is dead)
2)So I thoutgh lets see if the relay works with a 9V alcaline battery (the relay is a DSY2Y-S212L and is supposed to work at 12V). Didn't work, and when i checked the battery voltage it was 7.5V and counted down at a pace of 0.05V/second. I stopped at 6.9V and checked with another multimeter and it was 7.5V steady. Then I connected both multimeters and they both showed a fall 0.05V/second! Maybe the first multimeter draws some current while measuring voltage, but again does it make any sense? Is this any indication of the multimeter quality?