Tom,

This probably won't be much help, but for what it's worth:

It's been 20 years since I played around with one of these.  The center 
knob is a tapped inductor with maybe 12 positions.   I don't remember if 
the knob is notched to help get oriented, but  I think  most inductance 
is position "A" at around 7 o clock position.

The knob next to the  meter doesn't have full rotation and is used to 
adjust meter sensetivity.   You would use it to  back down the needle if 
it goes full scale, so  you wouldn't need to  worry about this knob.

The knob on the far right is a  variable capacitor.


To use without the meter is probably just going to be trial and error. 
   I would guess you have some sort of RFI problem you are trying to 
resolve.  You might just have to  try each tap setting on the inductor 
and  twiddle with the cap to  seeif the RFI goes away .   If you are 
only dealing with a band or two, this really wouldn't be  a big project. 
  Just make a note of  knob settings.

You might want to try the most inductance at the lower bands.
Just saw your post to the other Steve, and I'm really not sure you have 
to go back and forth between  this thing and ant tuner.  I remember just 
adjusting antenna tuner for good match and then tweaking the ground box 
to kill any buzz or whatever RFI was bedeviling me.


Hope this is of some help,  Steve KW3A


On 4/15/2013 12:12 PM, Steve Dresser wrote:
> Tom,
>
> If you had one, you could try putting a VCO across the meter.  That would
> give you some indication of what the meter is doing.
>
> Steve
>
> ----- Original Message -----
> From: "Tom Brennan" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Monday, April 15, 2013 11:25
> Subject: mfj 931
>
>
>> I've got an MFJ 931 artificial ground.  The unit has a meter on it that's
>> supposed to let you watch current and adjust both current and capacitance
>> with a
>> couple knobs of the unit itself.  Has anyone got a work around for that
>> meter?
>> I called MFJ tech support and spoke to Bob.  He was really unhelpful with
>> the
>> whole thing first telling me that you didn't need the meter because all it
>> shows is current and then telling me you had to use it to adjust the unit.
>> I
>> never could get him to tell me anything other than you didn't need the
>> meter.
>> That's the first time in years that I've ever had a useless response from
>> MMFJ's
>> tech support but I guess there's a first time for anything.  Therefore,
>> any
>> suggestions from any totals who don't have eyes around for using this
>> thing
>> would be appreciated.
>>
>> Tom
>>
>>
>> Tom Brennan  KD5VIJ, CCC-A/SLP
>> web page http://titan.sfasu.edu/~g_brennantg/sonicpage.html
>>
>
>
>