If T:VFKNOB will not change the RF frequency

Check the value of T:VFREQS (reading).  This should read 3.  If T:VFREQS = 3, and T:VFKNOB still does not change the RF freqency, this procedure will not help and you need more expert help.

If T:VFREQS does not = 3, do the following in order:

1. Set T:VEPGM[1] to 0.
2. Set T:VEPGM[2] to 1.
3. Set T:VEPGM to 0.

At this point, T:VFREQS should change breifly to 0, and then to 3.  The reading for T:VEPGM should read zero at this point as well.   T:VFKNOB should once again change the Tev RF frequency.  If you still have a problem with T:VFKNOB, you need more expert help.

If you need to use this procedure, please send an e-mail to Jerry Annala, and include whether this procedure worked correctly or not.