[R-390] Crystal Oven Heater Resistance

[Bob Camp]

Hi

Last time I looked the oven is sitting across the 24 volt winding of  
the transformer. A 100 ohm resistance would put about six watts into  
the heater. A five ohm resistance would pull *way* more than the  
transformer is rated for.

Bob



On Apr 22, 2008, at 6:19 PM, Mike Hardie wrote:

> Page 108 of my photocopied manual has a chart (Not numbered) for  
> some preliminary resistance checks when trouble shooting.  Pin J208- 
> F, on the RF deck, to ground is listed at not less than 100 ohms.  
> (Tubes pulled and presumably with HR202, the assembly with the 200  
> Kc and 17 Mc crystals, not pulled)  I measure approximately 5 ohms  
> on this radio.
>
> I tracked down the resistance to be the heater in HR202.  With HR202  
> pulled the resistance at J208-F is infinity.  Can anyone confirm  
> whether or not the manual figure of 100 ohms figure is correct?
>
> Mike VE7MMH
> _____________________________________________________________
> R-390 mailing list
> Home: http://mailman.qth.net/mailman/listinfo/r-390
> Help: http://mailman.qth.net/faq.htm
> Post: mailto:R-390 at mailman.qth.net
> Unsubscribe: http://mailman.qth.net/mailman/options/r-390
>