[AMRadio] Fw: Johnson Viking Matchbox

David Knepper collinsradio at comcast.net
Tue Feb 5 05:10:19 EST 2008

I wish to acknowledge the post that I received from Bob Sullivan, W0YVA, who assisted me in realigning the differential capacitor in my two Matchboxes, a 250 and 1 KW units.  

Bob told me that the differential capacitor (the one on the right) was positioned to where the rotor was half way inside each of the two (fixed) stator sections - the one on the top and the one on the bottom.    The knob is repositioned on the shaft to read "50" or midscale.  The rotor plates are positioned to the left inside the stator. 

I confirmed what Bob was telling me by removing the cabinet from a Matchbox that had never been opened.

Incidentally, when the knob on the left should read "100" when the rotor plates are fully meshed inside the stator.

E.F. Johnson did not include this information in the manual since, I imagine, they believed that no one had any business inside the unit to change the settings of the two variables when the tuning knobs were removed - WRONG!

Thanks, Bob.

Dave, W3ST - W3CRA

More information about the AMRadio mailing list

This page last updated 21 Jan 2018.