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Old 05-29-2012, 10:54 PM
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NickZ NickZ is offline
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Join Date: Mar 2010
Posts: 894
I can't explain it myself, it is still a mistery to me, just how or why that resistor makes a difference, but it does. Putting the same 3k resistor on the base, does not work, but putting it on the positive of the battery rail, and the transistor is stone cold, wireless working up to a foot of more away from the coil. I'm currently using a 100 k resistor on the base, with a small pot also. the 1n4148 diode between the emiter and base also seams to help. Outside ground to the base, doubles the light output.
The battery voltage reading at the transistor is about 6.5 volts, with the device running off of a 12v, 4.5 mAh LAB. I'll try to increase voltage carefully while keeping an eye on the transistor heat, as the wireless range is increased.
I am still having a bit of a hard time trying to figuring where to test for the current draw. It is just done by placing the meter in series between the battery positive and the control of the transistor?
For now, I'm very happy to be able to continue with this work.
I also hope that anyone else that has had this heat problem, will take note.
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