AM / FM mode switch, Special interest channels

engine or wiper as a signal and will open, because the squelch cannot distinguish between a wanted signal and an unwanted interference.

If You would have preset the ASC at switched-off engine before, the interference coming from the wiper motor would be detected and the ASC circuit would shift the threshold point so long automatically, until the interference will disappear.

The radio will remain muted, but stay on the highest sensitivity level during the whole procedure studied in this example.

That means: in most cases You only need to adjust the ASC knob to Your needs only once before starting. The setting will be maintained during travelling. The switching point is no sudden on-off point like the squelch, but a more smooth gliding effect between on and off. The best point is, where the background noise is just becoming so weak, that it does no more disturb You. A small background noise may remain.

Please do not turn the ASC knob too much into full clockwise direction. If You intend to suppress weaker signals which You do not like to hear, use the inner Squelch knob for this purpose and not the ASC knob. A symptom for too much closed ASC potentiometer is when weak speech still comes through, but louder speech no more.

AM / FM mode switch

In the two programming modes 40/40 and 80/40, FM modulation is available on all channels, but AM only on the 40 international CB channels. On these 40 channels you can switch between AM and FM using the function button F. The display shows either AM or FM accordingly.

When you switch on the set the first time it operates on FM.

Please note that in 80/40 mode, 41-80 it is not possible to operate on AM. If your radio is set to AM and you choose an FM channel, the radio will automatically switch from AM to FM. This is indicated by the FM symbol on the display starting to blink. If you switch back to a channel permissible on AM, the radio will switch back to AM.

Special interest channels

There are a few channels which have established themselves for certain purposes:

Channel 1	Call channel on FM
Channel 9	Call and emergency channel, also Trucker channel
	on AM in Germany
Channel 16	Water sport channel
Channel 19	Trucker channel on AM in France, Spain and Italy
Channel 24/25	Data transfer (Packet Radio, Germany only)
Channel 40	Calling channel in Switzerland

Some recommendations are being worked out by the CB clubs for the new channels 41 to 80 in Germany. To find out which channels are suitable for special purposes, please get in touch with the respective groups or check in CB magazines.