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THE AM BULLETIN BOARD => Technical Forum => Topic started by: W4AMV on September 09, 2017, 08:07:34 PM



Title: Ranger I VFO CAM switch position
Post by: W4AMV on September 09, 2017, 08:07:34 PM
Hello forum,

The bandswitch on a Ranger I has progressively
been difficult to turn. Cleaned the metal on
metal switch detent, no ball
bearing used here and the shaft bushing and all
is well. However, I forgot to take notice of the
VFO CAM position. Believe this is straightforward
but to be sure. The CAM first kicks in when moving from
160/80M to 40/20/15/10M and then kicks in again when moving to
11M. Viewing the Ranger CAM with the Ranger upside down and
power cord to the REAR, the CAM is fully CCW for 160/80M,
and sort of centered for 40-10M and fully CW rotation for 11M.
Correct? Thanks! Alan   


Title: Re: Ranger I VFO CAM switch position
Post by: N1BCG on September 10, 2017, 01:52:28 PM
That sounds correct because the VFO uses one tank circuit for 160 then doubles for 80. It uses another tank circuit for 40, doubles it for 20, triples it for 15, and quadruples it for 10.  11 is unmentionable except that it uses a separate mystery circuit. :-)

Based on your description of the cam movement, it seems to be right. Make sure you apply a heavy grease to the two pins and the slanted surfaces to reduce friction. Also, the adjustment of the cam on the shaft can be tricky.


Title: Re: Ranger I VFO CAM switch position
Post by: W4AMV on September 10, 2017, 07:47:18 PM
Excellent, thanks. Per Johnson manual I applied a thin coat of Vaseline. But I think I will remove and try a thin coat of white lithium grease. Also needed is some light grease on the shaft switch as it is just metal to metal no bearing to aid movement. Fortunately, the shaft pin assembly on the shaft as well as the cam were not removed. I simply rotated the cam out of position by hand without thought to its alignment with the shaft pin assembly on the band switch. 
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