ETS STW3-SEC Instructions

STW3-SEC Two Way Monitoring Kit Instructions
The STW3-SEC is a single zone 2-way Audio Surveillance System for use with all ETS STW1-SEC series microphone /
speakers. It can be used independently for monitoring live audio or with tape recorders for recording and playback.
STW1-SEC Mounting
Locate the STW1-SEC Microphone/Speaker near the area of interest. Do not mount the STW1-SEC near air conditioning
vents, light fixtures or electrical equipment. Try to keep the distance between the STW1-SEC and the STW2 under 500
feet.
Cable Run
For the Microphone, run a 22 gauge, 2 conductor shielded cable (1,000 feet maximum length) between the STW1-SEC
and the STW2 base station. Keep the cable away from AC power sources, light fixtures and electrical equipment.
For the Speaker, run a 22 gauge, 2 conductor shielded cable (1,000 feet maximum length) between the STW1-SEC and
the STW2. For the optional Call Switch, a 22 gauge, 2 conductor cable can be used. This is a contact closure type of
connection so it doesn't matter which side goes where,
Adjusting the STW1-SEC Microphone Gain
On the back of the STW1-SEC, near the center of the board, is an adjustment pot labeled "Gain". Use a small flathead
screwdriver and turn towards + or – for maximum clarity. If the sound at the amplifier is distorted, rotate towards the –
mark (counter clockwise). If the sound is too low, rotate towards the + mark (clockwise). Be careful not to move the pot too
far in either direction.
Setting the STW1-SEC Hi-Cut/Lo-Cut Switches
The normal frequency response of the SM1 microphone is 350-12Khz. When both switched "in", The "HI Cut" and "Lo
Cut" filters set the STW1-SEC's frequency response to 700-7Khz . Enabling one or both of the filters is useful when
background noise needs to be further reduced and intelligibility of speech emphasized. We recommend experimenting
with the switch settings to achieve the best acoustic result for your application.
Note- The STW1-SEC 70V/Line switch must be in the 70V position. Jumpers and volume controls do not function in the
70V mode.
STW2 Base Station Controls
After connections have been made, apply power to the unit and the system is ready to use. You should hear STW1-SEC
audio on the STW2 base station Speaker. Adjust the "Volume" knob to a comfortable level.
Sending a message to the STW1-SEC
Press and hold the "Push To Talk" button on the base station, and a green light will come on, indicating that audio is being
sent to the STW1-SEC. Speak in the direction of the Microphone, then release the button after you have finished your
message. The green light will go out. If necessary, you can adjust the Speaker volume by turning the "Remote Volume"
know clockwise for louder sound and counter clockwise for softer sound.
Recorder Switch
If the STW3-SEC kit will be used with a recorder of some type, place the recorder switch in the "IN" position. In this
position, both live audio and playback audio can be heard through the STW2's internal speaker. Connect the "Audio Out"
jack to the recording device's "Audio In", using the supplied RCA cables. Connect the "Audio In" jack to the recording
device's "Audio Out." In stand alone applications where there is no recorder or no need to playback recordings, place the
recorder switch in the "OUT" position. Note-both sides of conversations will be recorded.
Headphones
Plug headphones into the "Headphone" jack on the front panel of the STW2. Audio will be cut out on the STW2 Speaker.