3)“ON AIR” Indicator: Turn the power switch (1) “ON” and LED Indicator (3) will blink on and off to
indicate the receiving condition. The LED (3) will light up continuously when
transmitting.
4) Output Level Volume: Use it for control of output level. Adjust it to get an optimum level output. (It
has no concern with compressor control and please adjusts the level with
monitoring the meter pointer not to exceed “0dB”.)
5) PTT Switch: Use it for short time QSO. While pressing it, the TX LED Indicator lights up and the
condition is transmitting. (When press it, it sounds ‘pip’. When releasing the
LOCK condition also press this switch.)
6) LOCK Switch: Use it for long time QSO. Press it and it sounds ‘peep’. The LED TX indicator (3)
will light up continuously. The condition is in transmitting until pressing the
PTT switch (5).
7) UP/DOWN Switch: The same function as the UP/DOWN switch of transceiver. For details, please
read the instructions of transceiver.
8) Level Meter: You can watch the output level of AM-7500 with this meter. Adjust the output level not
to exceed “0dB”. Refer to (4) output Level Volume and (11) Graphic
Equalizer Volume Control. It works also as a battery checker for a few
seconds just after switching the power “ON”.
9) Mic. Output Connector: Connect with suitable conversion cable optionally available to transceiver. (8P
AVAIR type) (The conversion cables are provided with a directional condition
for connecting. Please connect with microphone correctly.) Terminals of
Microphone output Connector (9) and “AVAIR” standard terminal layout (8P)
(Fig. 2)
Compressor Area
Linearly amplified
COMP HIGH
V
COMP LOW
A B C D
10)Microphone : This model is provided with Ceramic type microphone for easy understanding
sound quality.
11) Graphic Equalizer: The Graphic Equalizer consists of 4 elements with center frequencies 270,
Adjustment Volume 540, 1000 and 2000Hz. The general characteristics including
microphones are designed as shown on the Fig.3 and you can change the output
character’s-Tics freely as shown on the Fig.3. If you speak in a low voice tone,
turn Down the volume of 270 and 540Hz and clear sound quality can be sent to
The transceiver. At DX operation, it is recommendable to slide up the higher tone
range, 1000Hz and 2000Hz to get the plain sound quality. When you are in local
QSO, turn down the volume of higher tone range and you can send the soft sound
quality. The level change of each element is about 12dB and when you increase
the all elements 12dB level, the output level of microphone should be increased by
12dB and you must turn down the output volume accordingly. (The above
condition will cause the distortion.)
12) The Lead wire for canceling the Non-Modulation Prevention Circuit.