Advanced Features

Scrambler

The scrambler inverts or transposes the audio frequency spectrum, making speech unintelligible to anyone not using the same scrambler frequency. This is not encryption — it is easily defeated with basic equipment. It provides minimal privacy.

• Master enable: Set Scram to ON in the menu to globally enable scrambler support.
• Scrambler frequency: Set ScrmFq to the desired audio inversion frequency. Both radios must use identical settings.
• Per-channel toggle: With the master enabled, toggle scrambler on/off per channel using F + 9 or via the channel settings.
• When active, SCR appears on VFO line 2.

Compander

A compander (compressor/expander) compresses audio on TX and expands it on RX, reducing background noise and improving intelligibility on narrow-bandwidth channels.

• Set via Compnd in the menu: OFF / TX / RX / Both.
• TX: Compresses your transmitted audio.
• RX: Expands received audio (best results when the other radio also compresses).
• Both: Full compander — both compress on TX and expand on RX. Requires both radios to use compatible compander settings.
• This is a per-channel setting.
• Without a matching compander on the other radio, the expanded RX audio may sound thin or distorted.

DTMF Features

DTMF (Dual-Tone Multi-Frequency) are the tones used in telephone keypads. The UV-K5 can decode incoming DTMF, transmit DTMF, display a contact name from decoded ANI, and send PTT ID.

Live DTMF Decoder

• Enable via D_Decd in the menu (ON by default).
• When DTMF tones are received, the decoded character(s) appear briefly on the center bar of the display.
• The decoder works in receive mode without any special setup.

DTMF Side Tone

• Set D_ST to ON to hear your transmitted DTMF tones in the speaker.
• Useful for verifying DTMF digits during transmission (e.g., when accessing autopatch or IRLP nodes).

Transmitting DTMF

• Short press * to enter DTMF input mode.
• Type the DTMF sequence using the numeric keypad (0–9, *, #, A, B, C, D via F-key).
• Press PTT to transmit the DTMF sequence. The tones are sent immediately.

Contact List

• Store DTMF ANI codes paired with contact names via D_List in the menu.
• When incoming DTMF ANI matches a stored entry, the contact name is shown on the display.
• Useful in dispatch/fleet radio systems where each radio has an ANI number.

Flashlight

The UV-K5 has an LED on top of the radio (next to the antenna) that functions as a flashlight. It has four modes.

Assign the Flashlight function to a side key for instant access. Long-pressing Side Key 1 activates the flashlight by default. Each press cycles to the next mode.

FM Broadcast Radio

The UV-K5 can receive commercial FM broadcast stations (76–108 MHz) using a built-in FM receiver mode.

• Access via F + 0 or the assigned side key function.
• Use UP/DOWN arrows to step through preset stations or tune manually.
• Long press UP/DOWN to scan for the next active FM broadcast station.
• Store presets: press MENU on a found station to save it as a preset.
• Up to 20 FM presets can be stored.
• The earphone/speaker functions normally during FM radio mode.
• Press EXIT to return to normal radio operation.

Alarm

The alarm feature produces a loud tone from the speaker and/or transmits a tone signal.

• Tone mode: Plays a loud alarm tone through the speaker. Useful as a personal alarm.
• Site mode: Transmits the alarm tone over the air so others can hear your emergency. Activates PTT automatically.
• Assign the Alarm function to a side key for quick activation.
• Press EXIT or any key to stop the alarm.

Aircopy — Wireless Channel Cloning

Aircopy allows one UV-K5 to wirelessly clone its channel list and settings to another UV-K5 using RF. Both radios must be running compatible firmware.

• Keep both radios close together (within 1–2 meters) for reliable transfer.
• Aircopy transfers all channel data and some system settings.
• The receiving radio's existing channels are overwritten.
• Aircopy uses a fixed frequency and protocol — do not transmit on other channels during the transfer.

Battery Calibration (BatCal / BatTyp)

If the battery voltage shown on the display doesn't match the actual voltage, calibrate it.

1. Measure the actual battery voltage with a multimeter on the battery terminals or USB charging port pins.
2. Access the hidden menu (power off, then hold PTT + Side Key 1 while powering on).
3. Find BatCal and adjust until the displayed voltage matches your measured voltage.
4. Set BatTyp to match your battery pack capacity (1600 mAh or 2200 mAh extended battery) for accurate percentage display.

Frequency Calibration (FrCali)

The UV-K5 uses a crystal oscillator that may drift slightly from the nominal frequency. FrCali adjusts the reference to correct this.

1. You need a calibrated frequency counter or a signal of known exact frequency (e.g., WWV time station on 5, 10, or 15 MHz).
2. Receive the known-frequency signal and compare the displayed frequency to the known frequency.
3. Access the hidden menu and adjust FrCali until the displayed frequency matches.
4. The calibration affects both receive and transmit frequencies.

Factory Reset

Two reset options are available via the Reset menu item (hidden menu).

Firmware Flashing

Flash rfsplatter firmware to your UV-K5 directly from the browser at rfsplatter.com/build.