STW2-DM Two Way Monitoring Station Instructions
The STW2-DM is a single zone 2-way Audio Surveillance monitoring station for use with all ETS speaker/microphones.
Speaker/microphone Placement
Do not mount the HSM6-DP speaker microphone near light fixtures or electrical equipment. The HSM6-DP should be
placed as close as possible to the subject(s) to be monitored for best performance of the microphone. The HSM6-DP’s
microphone is useable at distances of up to 25 feet but is dependent on the level of background noise in the area.
Experimentation in the environment will determine what distances work best.
Cable Runs and connection to HSM6-DP
Run 2 each 22 gauge, stranded, two conductor shielded cable between the HSM6-DP speaker microphone and the
monitoring device. If you will be using a call switch, run an additional 2 conductor shielded cable. To avoid crosstalk
issues, do not use a multiconductor shielded cable in place of the 3 cable runs. Keep the cable run distances at or under
500 feet and away from AC power sources, light fixtures and electrical equipment. See figure 1 for connecting the HSM6-
DP to the STW2-DM base station. Contact ETS for connections to other models of ETS speaker microphones.
Note- If you are picking up radio stations or 60hz hum in the microphone, try Earth or electrical grounding the “com“
terminal of the microphone pre-amplifier board. You can try this at the speaker microphone or STW2-DM or both.
Talking down to the remote Site
Normally, the microphone from the remote site is heard on the STW2-DM speaker unless muted (talk lamp flashing). To
speak, press and hold the orange talk button on the desktop mic, wait one second, then speak. The talk lamp will light
solid. When you’re finished talking, wait one second, then release the orange talk button.
Muting the STW2-DM speaker (remote microphone)
The STW2-DM features an auto timed mute function or an operator initiated mute of the remote speaker. Auto mute
happens when you stop pressing the orange button. After a period of time, set by the mute delay control on the front of
the STW2, the microphone at the remote site is muted. If the control is adjusted fully clockwise, the remote mic will never
be muted. Backing the control off to slightly past 3 O’clock will result in a 255 second (about 4 minutes) timed mute. To
mute the remote mic instantly, quickly tap the orange talk button. When the remote mic is muted the talk LED will be
flashing.
Note- whenever the operator releases the orange talk button, a quick succession of two tones will be heard on the remote
speaker to inform the person at the remote site that the operator has finished speaking and is now listening.
External speaker
Connecting a high quality external speaker to the STW2-DM can help improve the intelligibility of the remote microphone.
The TR of the 3.5mm stereo jack is s and the S is speaker -. A 4 or 8 ohm speaker should be used. When you
plug a speaker into this jack, the internal speaker of the STW2-DM will be disabled. Our WS5 speaker is an excellent
choice for an external speaker. You can also plug headphones into this jack.
Line Output
Use this output to record, or monitor from another location, both sides of the conversation that is occuring on the system.
Remote Volume
Use this control on the front of the STW2 to adjust the speaker volume at the Remote speaker location.
Mute delay
Adjust this control from 3 to 255 seconds. Adjusted fully clockwise, no timed mute occurs. Adjust this control to slightly
past the 3 O’clock position for a 255 second timed mute.
Optional Call Switch
This input is designed to signal the operator that someone at the remote location wishes to speak. Every 30 seconds, a
tone will be heard until the mic speak button of the desktop microphone is pressed. Connect a normally open switch to
these terminals if you wish to use this function.
