legg wrote:
On Fri, 23 Nov 2007 04:46:29 GMT, ehsjr
wrote:



Toroids work great for that. For fun, try it with an air
wound coil and red led. AIRC the one I made that way used
20t of #22 insulated, wrapped on a 1/4" bolt, then allowed
to expand and the bolt removed.


1.5 ---+------+---------+---------+
| | | |
[4.7K] [100uF] [100R] |
| | | |
| | [LED] |
| | | |
| | /c |
+------+-------| BC337 [coil]
\e |
| |
Gnd -------------------+----------+



I think you've misconnected the coil. It is shown across the battery
terminals.

RL

Ooops - right you are. Supposed to be connected to
the collector, not ground, and the 100R/LED goes
collector to ground, not collector to + :

1.5 ---+------+---------+
| | |
[4.7K] [100uF] [coil]
| | |
| | +---------+
| | | |
| | /c [100R]
+------+-------| BC337 |
\e [LED]
| |
Gnd -------------------+----------+