All VAX users & lovers.  I am now in possession of my 2nd VAX electric 700 ("Blue" is S/N 00000001, just got "Red").  BOTH guitars had a similar problem: when I would change the Model Select, the modeling would not change to certain models and/or would be "OFF" by one model  (e.g., changing from TELE to SPANK, the VAX modeling sounds would stay on TELE.  Then clicking next to LESTER it would model SPANK, etc.).

At first I figured it was the pot, so I ordered one & replaced it and got similar results, albeit on different model settings.  Browsing through the online community I came across the very helpful document, "Variax Troubleshooting Tips" created by Line6Miller and Line6Tony which, among other tips included the Model Select Knob Calibration procedure  (doc 3857 can be found at:   http://line6.com/community/docs/DOC-3857).

I've copied the procedure below.  This procedure WORKS GREAT IF you follow my two tips below.  NEITHER of my Variax 700's were corrected until I performed the FIRST TIP below, so I'm passing it on to the general user community as a minor but necessary addition.  I would have suspected BLUE, being serial number 1 might have some pre-production peculiarities, but it received a new motherboard and Model-Select pot ... neither solved my Model-Select problem.  Once I received RED today, with a much later serial number, I discovered the same problem and it required my extra two tips below before the procedure worked properly.

FIRST TIP, "SPLIT THE DIFFERENCE":  the model select potentiometer has more travel than the physical detent knob allows.  You can observe this by turning the selector to CUSTOM 1 (fully  counter-clockwise), then very carefully removing the knob entirely from  the stem of the pot while not allowing any pot rotation.  The pot can probably turn further CCW.  If not, place the Model Select back onto the stem, turn fully CW to CUSTOM 2 and pull the knob off.  You'll observe extra travel.  UNTIL I ROUGHLY SPLIT THE "EXTRA" ROTATION DISTANCE BETWEEN CUSTOM 1 (fully counterclockwise) AND CUSTOM 2 (fully clockwise), the calibration procedure failed repeatedly for both of my VAXes.  The procedure resulted, sometimes, in different model selections being missed, but always a model selection would be ignored/missed.

To SPLIT THE DIFFERENCE:

1. Turn Model Select to CUSTOM 1
2. Carefully pull (remove) the knob from of the stem of the potentiometer
3. Turn the pot fully CCW
4. Place the Model Select knob back onto the stem, making sure it's indicating CUSTOM 1
5. Turn the knob fully CW to CUSTOM 2
6. Again, carefully remove the knob from the stem, causing no stem rotation
7. Note how much extra travel the stem can turn to fully CW (you can place a post-it note or piece of tape at the base of the pot and mark the 2 positions, but I simply eye-balled it and got good results)
8. Now, turn the pot CCW, HALFWAY back to its original spot (where it was when you removed the knob at CUSTOM 2 in Step 6)
9. Carefully place the Model Select knob back onto the stem, making sure you don't rotate the stem any and it shows CUSTOM 2
   

(most of you VAX owners are rather technical, so I must apologize if the above steps are an insult to your abilities.  Please forgive me, I was a manufacturing engineer in my past life and discovered that very clear instructions were necessary in order to make a reliable, repeatably high-quality product.  If my steps offend, may the fleas of a thousand camels infest my loins).

SECOND TIP:  in the original procedure below, step #7 seems to indicate an audible beep sequence after power is applied and the circuits are initialized.  NEITHER of my VAXes produce this tone ... they wait patiently until I perform step #8, turning tone control down to min and then to max.  THEN they produce their first beep sequence and the rest of the procedure goes as written.

ORIGINAL DOC 3857 WITH MY ADDED TIPS/CLARIFICATION:

Q: How do I calibrate the Model Select knob on the Variax 500/700?

1. Unplug RJ45 cable from guitar.

2. Turn off Power (disconnect ¼" TRS cable from guitar).

PERFORM TIP #1 ABOVE, SPLIT THE DIFFERENCE IN THE EXTRA ROTATION OF THE MODEL SELECT POT

3. Turn the volume up.

4. Pull model selector to "up" position (set to Custom 1).

5. Set pickup selector to 4th (neck-middle) position.

6. Set tone knob to middle position.

7. Turn on power (connect ¼" TRS cable to guitar).

ONCE INITIALIZED (INDICATED BY AN THE AUDIBLE BEEP SEQUENCE AFTER PERFORMING STEP #8), YOU WILL HAVE APPROX. 13 SECONDS TO COMPLETE THE FOLLOWING PROCEDURE:

8. Turn tone control to min and then max.

9. You will now hear a beep sequence.

10.  Turn model selector from "Custom 1" through all positions up to "Custom  2" this should be timed to approximately 1 second per physical step.  (Counting: "one, one thousand", making sure to turn the pot on the one).

11. You will hear a low-high-low beep when completed.

12. Model selector will now be calibrated.

If  you hear the low-high-low beep prior to completing the entire rotation  of the model select knob, unplug the ¼" TRS cable from guitar and start  over again until the timing is correct.

Hope this helps,

1oldguitarman

2/24/11