VOS-1 VOICE OPERATED SQUELCH for SSB Single Sideband Radio from Naval Electronics

VOICE OPERATED SQUELCH

IMMUNE TO NOISE

DESIGNED SPECIFICALLY FOR SINGLE SIDEBAND RECEIVERS AND TRANSCEIVERS

Most SSB receivers today have a squelch that operates on the AGC threshold principle. When the incoming signal reaches a threshold as set by the squelch control, the squelch "breaks" and the audio circuit comes alive. This works well to an extent on AM and FM because a relatively steady carrier is involved. On SSB however, the incoming signal dances wildly in response to the human voice and the AGC threshold principle leaves much to be desired.

The voice operated squelch (VOS) is completely independent of noise level and signal level. It incorporates a special syllabic rate detector that recognizes human speech patterns even though the signal is weak and the noise level high and erratic. The VOS is surprisingly sensitive to voice, yet almost immune to static crashes and steady heterodynes.

Now the VOS is available as a tiny SMD thick hybrid module designed to fit inside most modern SSB radios. Connections are simply made to the low level audio stage, 12 VDC and to the supplied on/off switch. Only one simple initial balance adjustment is required to the tiny potentiometer, which is also supplied.

A Deluxe version is available for simpler connection direct to 8 ohm speaker leads. In addition, the Deluxe VOS has a DIP relay that will activate a cassette tape recorder for automatic recording when the radio channel is in use. Extra contacts are available to activate lamps or an alarm circuit.

The VOS circuit has been proven to greatly reduce operator fatigue when monitoring an SSB channel.

The VOS is perfect for Remote Control and Remote Monitoring applications

The VOS is used in Military, Avionics, Government, Marine and Amateur Radio equipment. Thousands in use since 1980... design has been minaturized since then but operation remains identical.

SPECIFICATIONS: VOS-1

Thick film hybrid module (SIP) epoxy coated
Module Dimensions: 1.4 x 2 x 0.25 inches
Deluxe VOS: 2 x 2.5 x 0.75 inches (Circuit Board with Module)
Operating Voltage: 4-14 VDC
Dynamic Range: greater than 90 db
Sensitivity: any 2 db change at syllabic rate
Current drain while squelched: 10 mA @ 4 VDC, 25 mA @ 14 VDC
Current drain while unsquelched: 2 mA less than above

Photos show the VOS-1 module mounted on a pcb as the "Deluxe"

Drawing of the Deluxe VOS shows possible connections

NEW VOS-4 IN DISCRETE COMPONENTS SHOWN BELOW

Ordering information
VOS-1 module alone $179.00 + 5.00 shipping continental USA NO STOCK
VOS-4 deluxe with pcb, relay, voltage regulator etc $249.00 + 5.00 shipping continental USA
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