Model 300VSC-1044SB SelecTone® Command Unit generates up to four tones or voice communications in a SelecTone system. The housing can be mounted in any standard 19" equipment rack. Four tones, auxiliary, test and cancel are controlled via an illuminated keypad. Voice transmission is activated by keying the optional desktop or hand-held microphone.
Public address can be accessed from the optional local microphone or the remote microphone input. Audio input allows background music to be played from any 1 volt peak-to-peak audio source. Public address has the highest priority, followed by tones 1-4, remote microphone and audio.
“Test” plays tones or voice messages through the monitor speaker only. “Cancel” interrupts any tone.
External dry contact closures can be wired into the command unit for automatic remote operation of the signal system.
Model 300VSC-1044SB SelecTone Command Unit is the basis for a simple, versatile general signaling system for weather warning, start and dismissal, general alarm, evacuation and paging.


Voltage 24VDC (Allows emergency power back-up using models PS250, PS600 or PS1000)
120VAC 50/60Hz
Mount 19" Rack
Operating Current 0.76 Amps at 24VDC
0.20 Amps at 120VAC
Standby Current 0.09 Amps at 24VDC
0.03 Amps at 120VAC
Tone Output - Unbalanced Signal Line 10Vrms (25 Ohm Maximum)
Tone Output - Balanced Signal Line (Recommended) 25Vrms (40 Ohm Maximum/15-watt)
Signal To Noise Ratio (<% 1.5 THD) Chip Input 67dBa
Signal Frequency Response 250Hz to 4.5KHz (typical)
Enclosure Rating Type 1
Height 3.500 in
Width 19.000 in
Depth 10.000 in
Net Weight 4.30 lb
Shipping Weight 7.90 lb

Ordering Information

Model Types
Model Description UPC
300VSC-1044SB SelecTone Command Unit, rack mount 782979391173
300VSC-1044SB2C Rack mount 300VSC with 2-channel mixer 782979219026
300VSC-1044SB4C Rack mount 300VSC with 4-channel mixer 782979223658
300VSC-IP4C Rack mount, 300VSC with 4 channels, IP capability 782979231820
TM33-SD Tone module, custom, Series D 782979227335
Product # Description UPC
MNC-1 Noise-canceling microphone, hand held, 300VSC-1 and 300SCW-1 782979402886
Replacement Parts
Description Part Number UPC
Tone Card Connector K2001164A 782979104872
Connector, 17 Position K140A332A-17 782979103356
Connector, 16 Position K140A332A-16 782979103349
PCBA, 300VSC-1 And 300SCW-1 K2001154E 782979124375
Switch Board K2001147A 782979104865