[Drake] T-4XB Crystal

[Garey Barrell]

Troy -

The correct crystal for 30M coverage is 20.8 MHz.  The reason for the 
"odd" frequency choice is that the carrier oscillator at ~5645 kHz and 
the PTO in the range of 4.9 - 5.5 MHz offer MANY possible spurious 
output frequencies around the desired output frequency.   This is 
"critical" for the transmitter, but not for the receiver.  In the 
receiver you only get "extra" signals as you tune through the 30M band.

Most of the crystal manufacturers can provide the proper crystal simply 
by telling them you need it for the Drake R-4 - T-4X series.

73, Garey - K4OAH
Atlanta

Troy Warren wrote:

>I need a crystal for my Drake B twins. I need a 20.mhz. rock for the
>operating frequency of 10.0 to 10.2 mhz. Anyone have an extra one that they
>can part with?
>Please contact me direct with info.  k5oh at ruralok.com 
>
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