[R-390] Band Switch Rocking (a new activity)

[wb3fau55 at neo.rr.com]

Hi Don,  how right you are  about the switch rocking.  I am now working on the original Motorola RF deck from  the project 390A.  The unit we  last  fixed is a Stewart-Warner RF deck.  So I had the intermittent gearset out of this deck and put it in another deck,  something else wrong  with this one, so I put it back in the Motorola.  So using the method of  measuring resistance reading on bands 0 thru 7 it works fine, running the switch clockwise.  Running it back counterclock wise,  it misses  the reading in the 2 to 4 range unless I rock it  back and forth.  So I do see some backlash in the gears, as likely the problem.  But this is an old 58 contract item. The  gears are gummy with dried up grease.
So I am cleaning up all this.  Lot of fun,  but it will look nice and work good when done-hi.  
---- Don Heywood <wc4g at knology.net> wrote: 
> Russ, more on the bandswitch... I have found that when I don't use one of my 
> 390's in a while I need to rock the bandswitch to get good signals. I think 
> you know that the bandswitch only moves between 'octaves', not with each MC 
> change. So what I do is rock the MC knob several times at the point where I 
> know the bandswitch will move. It moves between .5 and 1MC, then from 1 to 
> 2MC and then 2 to 4MC, etc.  I will rock the MC knob between 1 and 2, 3 and 
> 4, 7 and 8 and 15 and 16. This is where the switch moves. This sometimes 
> cleans up the switch. Hope I did not confuse you.
> Don
> 
> The storm is gone,  just another media-hyped non-event at this QTH 
>