[Hammarlund] The SP-600-VLF-31 and crystal control

[Kenneth G. Gordon]

The subject receiver has provision for 4 crystal controlled channels and 
VFO, very much like the other "X" marked SP-600s. It has a switch in 
the upper right corner of the front panel so marked.

As I remember it, the crystals go in the second-conversion oscillator, so 
their frequencies are, IIRC, in the 3 Mhz range.

I will dig out my SP-600-VLF-31 manual and look at it over the next 
couple of days, and will report back to the list.

Ken W7EKB