Lectrosonics R33 - Manual (Page 5)

Professional Wireless System
3. M33 SERIES TRANSMITTER
(see figure 1)
The GAIN ADJUSTMENT sets the audio gain of the M33 to match different performer’s microphones or instruments.
This adjustment is important to the proper performance of the system and is covered in detail in section 5, SYSTEM
SETUP AND OPERATION.
The INSTRUMENT INPUT is an RCA phono type with an input impedance of 100k. Use a good quality RCA plug
(Switchcraft) to insure a snug, noise free fit.
When the ON-OFF switch is pushed to the right it turns on the transmitter. An orange dot will be seen when the switch
is in the on position.
The THUMB SCREW is turned counterclockwise to remove the side cover in order to replace the battery. The battery
will not go into the compartment if it is put in backwards.
The BATTERY used in the M33 transmitter should be an Eveready No. 522, Malory MN1604, or equivalent 9 volt
alkaline battery (these batteries are available almost anywhere). Carbon zinc batteries, even if marked “heavy duty” or
“transistor,” will work for only a short while (4 hours or less). In addition, the battery indicator will not function properly.
The BATTERY INDICATOR will blink one time when the M33 is turned on and then go out if the battery is good. If the
battery is low, the battery indicator will begin to blink. After the indicator begins blinking you will have about 4 hours of
use remaining. When the battery gets very low, the indicator will glow solidly, indicating 1 hour or less remaining.
When the transmitter is first turned on, it may require several minutes to get a “true” battery reading. For example, if a
dead battery were not used for a day or so, and then was used in the M33, it might indicate for a minute or so that it
was good. This is just like the “dead” batteries in a flashlight that will shine brightly for a few minutes and then rapidly
go dim.
When in doubt, throw it out! Your performance is worth more than the few pennies you’ll save using questionable
batteries. And when you throw them, throw them hard so they can’t accidently get back into the transmitter. You
wouldn’t believe the number of transmitters we “repair” at LECTROSONICS by putting in a fresh battery.
The MICROPHONE INPUT is a standard 3 pin audio connector that will connect to standard microphones. Some early
microphones used a 3 pin connector but did not have a balanced output. These microphones will work with the M33 but
pins 1 and 2 must be wired together and the output must be on pin 3. Most of these microphones were wired this way
originally.
Though the microphone input will work with high impedance microphones it was designed for best performance with a
low impedance mic of 50 to 600 ohms. If your microphone has selectable impedance, set or wire it for 150 or 200
ohms.
Rio Rancho, NM – USA 5