====== Microphone Model 705 ======
{{705.jpg?150|}}{{705btm.jpg?150|}}

===== Description =====
The Ten-Tec Model 705 is an Electret desk microphone designed for use as a station microphone in commercial and amateur radio communications and in public address and paging installations.  The microphone consists of a base section and flexible gooseneck mounted microphone.  The Model 705 incorporates a momentary type Push-To-Talk (PTT) button (gray), a Push-On, Push-Off locking type button (black), electronic circuitry to switch the microphone on, a signal amplifier that adds 13 dB of gain to the output level, an attached output cable and a battery compartment for a 9 volt alkaline battery.  The PTT circuitry allows switching transmitters and/or transceivers, that have a low voltage positive T/R lines, into transmit mode.  A light emitting diode in the base signals the transmit mode.

The Model 705 comes in two versions.  The standard unit includes a four pin standard locking type cable connector which is pin compatible with Ten-Tec Models [[560]], [[561]], [[562]], [[563]], [[564]] and [[585]].  With a minor resistor change in the Models [[560]] and [[561]], the standard unit may be powered from the transceiver without the need for a 9 volt battery.  The Model 705-A comes with a stereo 1/4" phone plug.  This unit is compatible with the Ten-Tec Models [[525]], [[540]], [[544]], [[515]], and other early models.  A 9 volt battery is required for the Model 705-A.

===== Difference Between the 705 and 706 =====
The 705 and [[706]] are essentially the same.  The 706 does not have the compartment in the bottom to hold a 9V battery to supply voltage for the electret mic and circuitry.  The [[706]] only works with rigs that supply the necessary voltage through the mic connector whereas the 705 can operate from rig voltage or battery.  Also the 705 has a switch on the bottom to tell the controls on the mike base if you operate VOX or PTT.  The 705 has a bit more versatility for use with older transceivers not having voltage present at the mic connector for the electret mic.

===== Corsair Modification =====
The documentation that accompanied the 705 microphone included information on modifying a Corsair I or early Corsair II (s/n before 1970) to power the 705 microphone.  The modification involves shunting an existing 10K ohm resistor on the IF/AF board with a 470 ohm 1/2w resistor.

===== Mods & Tips =====
  *[[705gain|705 Gain Mod]]
  *[[705lowout|705 Low Output]]
  *[[705conn|Connector Wiring]]
  *[[706-588wiring|Wiring Diagram]] for an 8 pin connector

===== Specifications =====
  ***Type:** Electret Condenser Microphone.
  ***Sensitivity:** -52 dBV (0 dBV = 1 V/uBar @ 1 kHz).
  ***Output Impedance:** Works with any circuit of 100 ohms or more.
  ***Maximum Sound Pressure Level:** 130 dB
  ***Battery Type:** 9 volt Alkaline transistor battery.
  ***Electronics:** C-Mos PTT switch, C-Mos signal amplifier, NPN T/R transistor.
  ***Current Required:** Receive mode:  Less than 2 microamperes.  Transmit mode:  2 milliamperes typical, with 9 volt battery.
  ***Semiconductors:** 2 IC's; 1 Transistor; 7 Diodes.
  ***Weight:** 12 oz. including battery.