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Old May 5th 05, 12:42 AM
John Smith
 
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Richard:

If I use that at QRP levels, then go to QRO, that constant current source
will be used! I have a couple of burnt leds which offer proof... at a KW
the fet would wave bye-bye (even before I suspect)...

Regards,
John

"Richard Clark" wrote in message
...
| On Wed, 4 May 2005 16:13:10 -0700, "John Smith"
| wrote:
|
| And, that current source works, I have used it many times (makes an
| excellent test lamp for 5-30V)... will with stand at least 30V+ across
drain
| and source and maintain ~10ma... when the REV current to its' led drops
to
| zero, max flows though the FWD--all other cases they must share that
10ma...
|
| Hi Brett,
|
| I've no doubt, but in your circuits - never. Doesn't make sense
| unless you need parts ballast. It's like when the watchmakers
| advertised watches with 60 jewels, and there were only half a dozen
| points that actually used them.
|
| 73's
| Richard Clark, KB7QHC