JK Audio RemoteMix 3 - Manual (Page 6)

6
To test the batteries, simply press the Battery Test button on the
front of the unit. If the LED lights, the batteries are still good. The unit
may still function if the LED does not light, but there will be significant
audio distortion and a loss of level as the batteries continue to
discharge.
The batteries are wired in parallel so it is important to replace both at
the same time with identical batteries. If two fresh batteries are not
available, it is better to run using only one good battery. The two
battery fixtures are wired in parallel so it does not matter which one
gets the single battery.
We also provide a high quality, regulated AC to DC adapter to power
RemoteMix 3 / 3.m when AC power is available. Simply plug it into
the back of RemoteMix 3 / 3.m and plug the transformer into a 110
VAC wall outlet. When the power connector is inserted into the jack,
the batteries are bypassed. The AC adapter does not charge the
batteries. Remember to NEVER use a different power supply than
the one that was provided with the unit. Serious damage and poor
performance could result.
Operation (continued)
Hybrid Null Adjustment
(optional)
The receive side of RemoteMix 3 / 3.m has a hidden fine tuning
control which is adjusted by inserting a screwdriver into the back of
the unit just below the words Null Adj. and turning left or right. This is
a ten-turn potentiometer. This adjustment controls the level of
transmit audio that appears on the Receive audio jacks. The null
circuit matches the characteristics of RemoteMix 3 / 3.m with the
characteristics of the telephone line. Although much of the transmit
audio can be removed, this is not the equivalent of a mix-minus
output.