Tweaking the Airline 77 AH1 Transmitter

If you purchased this system elsewhere or have reason to alter the transmitter output of the AH1 transmitter paired with your receiver, this is a simple process that is accomplished from within the battery compartment of the transmitter and requires the use of the very small plastic screwdriver included with your microphone (contained within the carrying case when shipped to you). If you have lost this screwdriver, a small slotted screwdriver contained within an inexpensive "jeweler's screwdriver" set (obtained from Radio Shack, Home Depot, etc.) for just a few dollars will do the trick. Do not attempt this with a philip's head screwdriver!

The Basic Steps:

1. Remove the battery compartment cover from the AH1 transmitter.

2. Identify the small (about 3.5 mm diameter) hole adjacent to the positive end of the battery (see diagram below)

3. Carefully look down the hole and identify, if able, the orientation of the slot in the small screw at the bottom of the hole.

4. Insert the plastic screwdriver and maneuver and rotate as necessary to engage it in the slot. It may take a slight "push" to get the screwdriver all the to the bottom of the hole and engaged with the screw. Since this is done somewhat blindly it is a bit "hit and miss", but when the end of the screwdriver finds its way into the slot, you'll feel it.

5. Carefully rotate the screw clockwise to increase the transmitter volume (for speech recognition we recommend rotating it all the way clockwise). Alternatively, if necessary, rotate the screw counter clockwise to reduce the transmitter volume. Do not use excessive force when rotating this screw!

When the volume is optimally set on the transmitter, you should see 2-3 green bars illuminate on the "AUDIO METER" portion of the CR77 receiver. It is not necessary to see 4 bars, and it is too much if you see 4 bars.

6. After making an adjustment, test the transmitter and receiver to assess the results. Remember, if you turn up the transmitter volume on the AH1, you will likely not need quite as much output volume on the receive (adjusted with the large volume knob on the receiver).

7. Replace the batter cover.

You're done!