[Johnson] Ranger

[W5HTW at att.net]

<<Hello guys...
 
I would appreciate some advice as to where I should start looking.
 
I have picked up a Johnson Ranger that looks to be in good condition. All functions work and I get about 30 watts output on my watt meter.
 
The problem is, on the lower bands, I get the most output on my watt meter when the Johnson's meter shows it to be out of resonate.  Adding to this my Plate current never goes above about 100 MA.  The manual indicates I should be able to dip this rig at about 130 MA.
 
I've checked the rectifier tube..in fact, all the tubes. I also put in a new 6146.
 
Can one nuturalize the Ranger?  Why would I be getting such poor plate output?  I don't think my transformer is defective.
 
Thanks for any advice!
 
K7NCE>>

The most common cause of max RF occuring off resonance is indeed neutralization.  

However, the fact that off resonance you don't even draw 100 mil, suggests other problem.  This is usually a bad (soft) tube.  In your case, it is probably a voltage problem.  I would think that either the plate and screen voltages are off quite a bit, and/or a clamp tube (not sure if the Ranger uses one - I'm just going on general theory) or screen resistor has changed value dramatically.  Or the mechanical setting on a power divider resistor is wrong.  

You need to measure plate voltage (with no RF applied!) on the final, as well as screen voltage. 

Reduced voltage, though is not going to cause the dip and the RF peak to be at different places.  That could be a couple of things, but again, lack of proper neutralization is the most likely cause.  It is possible, of course, the final is being tuned to a harmonic.  That could cause a  similar symptom, but would not likely cause the inability to draw over 130 ma plate current off resonance.  

Ed