stabo xm 4060e, Operating Instructions Manual, Page: 21 / 32

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The SQ/ASC control is the outer knob of the double potentiometer. By turning the knob to the
left, the signal level is reduced, by turning the knob to the right, the signal level is increased. With
constantly varying conditions of reception, as for example during mobile operation, a frequent
adjustment of this level can be necessary.
(A)utomatic (S)quelch (C)ontrol
The ASC function is a patented function elaborated by the President Electronics SA France
group.This function evaluates the so-called signal-to-noise ratio (ratio between the useful signal
and the interfering signal).The useful signal is only forwarded to the loudspeaker, if it is worth
being received, i.e. it is almost free from noise.Thus, a permanent readjustment, as for the squelch
function depending on the field strength, is not necessary. This is of benefit to a safe participation
in the street traffic when driving.The ASC function can be used for AM and FM mode and is
activated if the squelch control is set to the leftmost position. Furthermore, ASC appears on the
display.
Choosing the type of modulation (AM/FM)
Using any channel configuration (except EC) you can either operate your radio set in FM or in
AM modulation. Frequency-modulated signals (FM) are less sensitive to interferences resulting
from the ignition system etc. than amplitude-modulated signals (AM). The decision, which type
of modulation is your preferred one, depends on your radio contact partners and on your and/or
the legal requirements.
If your loudspeaker emits an unintelligible, distorted signal, you should try receiving the signal
using a different type of modulation. You can change the type of modulation by a short key stroke
on the AM/FM key.
Receiving
When the radio set is switched on, it is ready-to-receive, unless the set is transmitting.
Transmitting (Attention: Never transmit without having an antenna connected!)
Before starting the transmission, listen to make sure that the channel is free and that there is no
„doubling” with a different radio station! Please note that the radio station needs a certain time to
carry out its start-up sequence: Thus, you should wait for a second before speaking.
For transmitting, you just have to press the
PTT button (push-to talk button) on the left side of
your microphone and to speak with normal voice level into the microphone while holding the key
pressed. Don’t speak too loud such that the sound of your voice is natural for your radio contact
partner. (Simply give it a try and ask for a modulation report afterwards.)
VOX function
The VOX function allows transmitting by speaking into the microphone without pressing the PTT
button. The use of an optional VOX mike (connected to the back side of the radio set) disables
the original microphone.
Activate/deactivate the VOX function by a short key stroke on
VOX , VOX appears/disappears on
the display.
VOX settings (VOX SET)
First you activate the VOX function (short keystroke) and then (with a long key stroke on VOX
SET) you enter the setting mode. Three settings are available: sensitivity, Anti-VOX and delay
time. You adjust the requested values by rotating the channel selection knob (or the up/down-
keys on the microphone), and with a short keystroke on VOX you change to the next setting.
The sensitivity allows adjusting the response sensitivity of the microphone (original mike or
optional VOX mike), means the threshold at which the VOX switches over to transmit mode.
9 levels are available: from 1 (high) to 9 (low); the selected level is indicated on the display.
The
Anti-VOX function is used to avoid that the VOX switches over to transmit mode caused by
RX signals or surrounding noise. The level is adjustable from 0 (off) to 9 (low level); the selected
Anti-VOX level is indicated on the display.