IC-R15 Receiving: Dualwatch, Squelch, Modes & Tuning

Summary: How to receive with the IC-R15: the two bands and Dualwatch, VFO tuning, receive modes, squelch, the attenuator, AF filter, noise limiter and other receive functions.

Two Receivers: Dualwatch

The IC-R15 has two independent receivers, the A band and the B band, each with its own frequency and mode. When Dualwatch is on, the display shows A in the upper half and B in the lower half.

• Turn Dualwatch on or off: hold D-pad up for 1 second. With it off, the display shows only the MAIN band, and D-pad up/down switches between A and B.
• MAIN band: push D-pad up/down to alternate. The MAIN band (shown by an icon) is where you change settings; band selection, frequency, receive mode, memory channel selection and Memory Write work only on the MAIN band.
• The SUB band can be muted automatically (SET, Sounds, Sub Band Mute).
• The FM Radio can be used only on the A band.
• Because the two receive circuits share the antenna, you may hear noise or interruptions when one band switches frequency during a scan. That’s normal. If a spurious signal shows up on certain frequency combinations, try SET, Function, Heterodyne.

Selecting How You Tune

• VFO mode ([V/MHz]): rotate [DIAL] to set a frequency. Push [V/MHz] again for 1 MHz steps (the MHz digit blinks).
• Memory mode ([MR]): rotate [DIAL] to choose a memory channel (see IC-R15 Memory Channels: Groups, Categories & Editing).
• Weather Channel mode (USA version only, [MR] toggles it).
• FM Radio mode: see IC-R15 FM Radio Mode.

Receive band: in VFO mode push [QUICK], choose Select Band, and choose the band (or push D-pad left/right).

Tuning Steps

Push [QUICK], choose TS and choose 5.0, 6.25, 8.33 (VHF Air band, 108.000-136.991 MHz only), 10, 12.5, 15, 20, 25, 30, 50, 100, 125 or 200 kHz. The step applies to both VFO and Memory mode, and VFO scans and the Band Scope function use it too. Use 8.33 kHz for UK airband.

Receive Modes

Push [QUICK] and choose MODE: FM, FM-N (narrow FM), AM or AM-N. Airband is AM; most UK land-mobile and marine voice is FM or FM-N.

Squelch

Hold [SQL] and rotate [DIAL]. Options: OPEN, AUTO (default; an automatic level using noise-pulse counting) and LEVEL 1 to 9 (1 is loose, for weak signals; 9 is tight). In FM Radio mode you can go up to LEVEL 3.

Monitor: hold [SQL] to listen on the frequency with the squelch open (to hear weak signals without changing the squelch). Change SET, Function, Monitor to Hold to have each push open and close it.

Attenuator

Push [QUICK], choose ATT and select ATT1 to ATT4 (higher is more attenuation). It prevents distortion from a strong nearby signal, or from a broadcast transmitter close by. It’s set separately for A and B.

AF Filter, ANL and VSC

• AF Filter suppresses high-pitched tones (per band and mode): QUICK, AF Filter, ON (“FIL” shows).
• Automatic Noise Limiter (ANL) reduces noise in AM and AM-N: QUICK, ANL.
• Voice Squelch Control (VSC) opens the squelch or stops a scan only when voice is detected, in FM and FM-N: QUICK, VSC.

Key Lock

Hold [MENU] for 1 second to turn Key Lock on or off (“LOCK ON” shows if you press a locked key). [POWER], [SQL] and [VOL] still work in the default mode, and SET, Function, Key Lock changes which keys lock (Normal, No SQL, No VOL, ALL).

Other Function Settings

SET, Function also has Frequency Selection Range (In-band or All bands when you reach a band edge), Memory Selection Range, Dial Speed-UP and Auto Power OFF / Power Save. See IC-R15 SET Mode Reference.