Technical data

VHF/AM RADIO FSG 2T

4 Recommended Set-up Sequence

46 FAV_D10048 June 2014

4.3 Adjusting the Headphone Volume and Transmitter Sidetone

IMPORTANT!

 This setting determines the maximum headphone audio volume

during Receive, Transmit (Sidetone), Intercom and AF External (if

applicable)!

 Transmitter Sidetone is not adjustable by the VOL knob!

 Before adjusting the Transmitter Sidetone volume, the microphone

sensitivity should be adjusted correctly (refer to § 4.2).

 Only during Transmit TX Sidetone is audible via headphone(s)/headset(s).

 When using two headphones their characteristics should be identical,

otherwise their audio volume will differ.

 Prior to Sidetone level adjustment set volume control(s) on each headset to

maximum, if applicable.

 During this adjustment the transmitter is active. Carry out

adjustment(s) quickly!

 Select an appropriate (test) frequency, e.g. 122.90 MHz.

 Press the PTT key. The TX/RX LED should light steady RED. Speak loud, clear and

close into one microphone. Observe the TX/RX LED, it should flicker YELLOW. Listen

to the TX Sidetone in your headphone; it should be clear and undistorted.

 If the TX Sidetone is too quiet or too loud, turn with a suitable screwdriver "Phone"

level potentiometer till the TX Sidetone audio volume is at a convenient level while

transmitting and speaking.

Phone

 If the TX Sidetone is distorted the microphone amplifier may be interfered by the

own radiated transmitting power, especially when the microphone is very close to the

antenna. To find out check the following:

a. Vary the position of the headset/microphone cable(s) against the antenna while

transmitting and listening to the TX Sidetone.

b. Operate the transmitter temporary on a 50-Ohm dummy load instead of the

antenna. No acoustical difference may occur between transmitting with antenna

and transmitting into the dummy load.

c. Check the quality of the TX Sidetone using another type of microphone (first

adjust the microphone sensitivity according § 3.5.2.1 and § 4.2).

 Try another type of headphone to find out if the earphone capsules cause the

distortion. Vary the headphone volume by turning the phone level potentiometer at

steady way of speaking.