[Milsurplus] BC-474

[Al Klase]

Good idea Dave.

ID8's and 3A8's can be a little hard to find.  Where my soldering iron?

Al

On 3/30/2010 6:07 AM, David Stinson wrote:
> ----- Original Message -----
> From: "Al Klase"<al at ar88.net>
>
>
>    
>> Meir and the Group,
>>
>> I built a 12-volt supply based on a DM-64A dynomotor...
>> ...  You can see the schematic here:
>> http://ar88.net/skywaves/SCR-288_Power.pdf
>>      
> That is very cool, Al!
> I would add this:  put a 1/2 or 3/4 Amp fuse
> in the 1.5 V filiment buss.  After the fuse, put three
> (3) silicon power diodes in series to ground.
> The diodes won't conduct unless the filament  buss
> goes over 2.1 Volts.  That way, if the LM-317 fails
> (and they occasionally do), the fuse pops instead
> of the tube filiments.  Cheap insurance.
> 73 Dave S.
>
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-- 
Al Klase - N3FRQ
Jersey City, NJ
http://www.skywaves.ar88.net/