Note
The TEN-TEC Model 705 is an electret desk microphone. It features a flexible gooseneck mounted on a stable base.
The microphone is designed for ease of use, incorporating two types of switching: a gray momentary PTT button and a black locking push-on, push-off button. An integrated LED in the base provides a visual signal when the unit is in transmit mode. Internally, the Model 705 features a signal amplifier that provides 13 dB of gain to the output level.
Specifications
Type: Electret Condenser Microphone.
Sensitivity: –52 dBV ( @ 1 kHz).
Output Impedance: Compatible with any circuit of 100 ohms or more.
Maximum Sound Pressure Level: 130 dB.
Semiconductors: 2 ICs, 1 Transistor, and 7 Diodes.
Electronics: C-MOS PTT switch, C-MOS signal amplifier, and an NPN T/R transistor.
Battery: 9-volt alkaline transistor battery.
Current Consumption: < 2 ua receive; typically 2 ma transmit.
The Ten-Ten 705 microphone is compatible with several different radio models depending on which version of the microphone you have.
Standard Model 705 (4-Pin Connector): 560 Corsair, 561 Corsair, 585 Paragon, Corsair II (with a small modification).
Model 705-A (1/4" Stereo Phone Plug): 525 Argosy, Models 540 and 544 Triton, 515 Argonaut. and other early Ten-Ten models.
Technical Notes
Power Requirements: While the 705-A requires a 9-volt battery , the standard 705 can be powered directly from Corsair transceivers if a minor resistor change is made to the radio.
Switching Capabilities: The microphone's PTT circuitry is designed to switch transmitters or transceivers that use low-voltage positive T/R lines. It can also be used to close a relay for switching other types of units, such as grid block keyed transmitters.
