[R-390] 200KC calibration crystal source

[Bob Camp]

Hi

The little oven that the cal crystal and 17 MHz crystal sits in  
actually works pretty darn well. The big "heated chamber" that the  
rest of the crystals sit in is useless. The PTO heater is also pretty  
useless.

Bob


On Mar 30, 2007, at 5:43 AM, Phil M. wrote:

>
>>
>> Taking the 17 MHz crystal out of the oven is not going to help the  
>> stability of the radio much at all.
>>
>
> I don't think it will hurt the stability of the radio much at all  
> either for
> typical swl and amateur.  It is used only on the bands up
> to 8 mc.  Many other fine receivers are quite stable with none of  
> their
> xtals in ovens.  Many of us use our  R-390A's with the ovens turned
> off anyway.
>
> thnks, Phil
>
>