Operation; Top / Tm8000 Switch; Top Mod Audio / Off / Mic Audio Switch; Hook On / Hook Off Switch - Tait TM8200 Installation And Operation Manual

2.2

Operation

2.2.1

TOP / TM8000 switch

2.2.2

TOP Mod Audio / Off / Mic Audio switch

2.2.3

Hook On / Hook Off switch

Tuneup
August 2004 © Tait Electronics Ltd
This section explains the function of the TOPA-SV-024 test unit controls.
The procedure for using the test unit is described in the section of the
TM8200 Service Manual covering test equipment.
This 2-way toggle switch is used to switch attenuation resistors (R4, R5, R6)
in and out of the line from the radio's positive speaker output to the positive
receive audio/SINAD output of the test unit (before the isolating transformer).
When set to TOP, the attenuation resistors are switched out.
When set to TM8000, the attenuation resistors are switched in
(attenuation 10:1).
Important
Selecting the wrong switch position can result in incorrect
SINAD readings.
This 3-way toggle switch is used to switch between Mod Audio (Tait Orca
portables only), Mic Audio, and Off (no audio signal).
With the Tait Orca portables, this switch can be used for setting up dual
point modulation by applying modulation to different parts of the radio.
For normal transmit deviation tests (Tait Orca portables and TM8200),
this switch is set to Mic Audio.
Important
When using the test unit with Tait Orca portables, the
Hook On / Hook Off toggle switch must be set to
Hook Off. Tait Orca portables do not have a hookswitch,
and if the switch is set to Hook On, the Tait Orca portable
F1 function is activated.
This 2-way toggle switch is used to simulate the microphone hookswitch
opening ("hook off") and closing ("hook on"). This is done by switching a
12kΩ resistor (R3) in or out of the MIC_PTT line.
When set to Hook Off, the 12 kΩ resistor (R3) is switched out of the
MIC_PTT line. This simulates the microphone being removed from the
microphone clip.
When set to Hook On, a 12kΩ resistor (R3) is switched into the
MIC_PTT line. This simulates the microphone being placed on the
microphone clip.
TOPA-SV-024 Test Unit 26