Proceed at your own risk. Entering the service menu and changing values incorrectly can:

Recommendation: Write down the original value of every setting you change. Do not adjust anything unless you own a calibrated frequency counter, a watt meter with a dummy load, and an oscilloscope (for modulation).

Legal warning: Check your local license limits. In the US, CB is limited to 4W AM / 12W PEP SSB.

The method differs slightly depending on the specific firmware version of your radio, but the following method is standard for the N-II series:

Method A (Standard):

Method B (Alternative - if A fails):

I’ve used the service menu on my AT-5555N II to gently bring my AM carrier down to 4W (for driving an amp) and to calibrate the frequency drift after warm-up. It’s a powerful tool, but treat it like surgery—make small changes, test, and always document your original settings.

Have you been inside your AT-5555N II’s service menu? Share your experience below (without breaking FCC rules, of course).

73 and happy tuning.

The AnyTone AT-5555N II is a powerful, high-performance 10-meter radio that has gained massive popularity among hobbyists for its high output and flexibility. While the standard settings menu covers most day-to-day needs, many advanced users look for the "Service Menu" (or Hidden Menu) to fine-tune the radio's hardware performance, such as power output levels and modulation depth. Understanding the Service Menu

Unlike the standard Function menu, the service menu is designed for factory calibration. Accessing it allows you to adjust internal parameters without opening the case and turning physical potentiometers. Important Safety and Technical Considerations

Before considering any modifications to the internal settings of a transceiver, it is vital to understand the risks involved. The service menu is intended for use by qualified technicians with specialized calibration equipment.

Risk of Hardware Failure: Adjusting power output levels or modulation depth beyond factory specifications can cause the final power transistors to overheat and fail.

Regulatory Compliance: Transceivers must operate within specific technical parameters set by national communications authorities (such as the FCC or Ofcom). Unauthorized adjustments can cause the radio to transmit out of band or create interference, which is illegal.

Warranty Concerns: Accessing hidden menus and changing factory-calibrated settings typically voids the manufacturer's warranty. Proper Equipment for Alignment

If a radio appears to be off-frequency or the power output is inconsistent, it should be checked using professional tools, including:

A Calibrated Dummy Load: To prevent broadcasting interference during testing.

A Frequency Counter: To ensure the reference oscillator is accurate.

An Oscilloscope or Spectrum Analyzer: To monitor modulation quality and ensure no spurious emissions are being generated. Recommended Maintenance Practices

Instead of accessing the service menu, most users can optimize their AnyTone AT-5555N II experience through standard operations:

Using the Programming Software: Many operational features can be customized safely using the official PC software and a USB programming cable.

Optimizing the Antenna System: Ensure the SWR (Standing Wave Ratio) is as low as possible. A well-tuned antenna is more effective for performance than "cranking up" internal power settings.

Consulting a Professional: If the radio requires alignment, contacting a certified radio technician ensures the device remains reliable and compliant with local regulations.

While the curiosity to explore the full capabilities of the AT-5555N II is natural, maintaining the factory calibration is generally the best way to ensure the longevity and legal operation of the equipment.

The Anytone AT-5555N II service menu allows for deep internal alignment and calibration. Because there is no factory reset for these settings, it is vital to record every original value before making changes. 🛠️ Accessing the Service Menu To enter the service menu, follow these steps exactly: Ensure the radio is OFF.

Press and hold the MENU and MODE buttons simultaneously while turning the power ON.

All LCD segments will illuminate for approximately 2 seconds.

Within those 2 seconds, release the buttons and immediately press the following buttons in sequence: RB, NB, SCAN, MEM, EMG.

Alternative method: Some versions require holding FUNC while powering on, then pressing the other buttons in the top row (DW to EMG) in order. ⚙️ Navigation and Controls

Scrolling: Use the Channel Selector or VFO knob to cycle through the menu items (there are typically around 53 parameters).

Viewing Values: To see the current numerical value of a setting, press the PTT (key the mic).

Changing Values: Hold the PTT and rotate the Channel Selector or VFO knob to adjust the value up or down.

Saving/Exiting: Power cycle the radio (turn it off and back on) to save settings. 📝 Common Service Menu Parameters

While documentation is limited, users have identified several key settings: CH-52 RFG

Often used to reduce high background noise (S5-S7) present on some units. bfC, fr0-fr9 Frequency Alignment

Used to calibrate the carrier frequency for different modes (USB, LSB, CW). AM Modulation AMC / Modulation

Adjusts the clamping level; smaller values typically equal higher modulation. ⚠️ Critical Warnings

No Factory Reset: Performing a standard CPU reset (FUNC + SCAN at power on) will not restore service menu values to factory defaults.

Record Everything: Always write down every value for all 50+ menu items before changing anything. If you lose your original settings without a backup, the radio may require professional realignment with a signal generator.

Equipment Required: Many frequency-related settings (like fr0) should only be adjusted while using a high-precision frequency counter or signal generator. Anytone 5555n Ii Service Menu - Google Groups

Here’s a detailed feature-style article on the AnyTone AT-5555N II Service Menu, written for radio enthusiasts, techs, and CB/Ham operators who want to unlock the full potential of their rig.

Once inside:

The AnyTone AT-5555N II has cemented its reputation as a powerhouse in the CB and 10-meter amateur radio community. Known for its robust build, excellent receiver sensitivity, and impressive power output straight out of the box, it is a favorite for DX enthusiasts and local communicators alike.

However, beneath the surface of its user-friendly LCD display and multi-function buttons lies a hidden layer of calibration: The Service Menu.

For the average user, the standard menu suffices. But for the technician, the power user, or the owner trying to restore a drifted unit to factory specs, the Service Menu is the Holy Grail. This article provides a complete, technical walkthrough of the AnyTone AT-5555N II service menu, including access codes, navigation, adjustable parameters, and critical safety warnings.

Note: Your stock values may vary. Write them down before changing anything!

| Menu Item | Function | Typical Adjustment | |-----------|----------|---------------------| | S-01 | PLL Reference Frequency (Coarse) | Adjust for frequency counter accuracy | | S-04 | AM Power (Low) | Sets carrier level on AM mode | | S-05 | AM Power (High) | Sets peak AM power | | S-07 | SSB Power (Low) | ALC threshold for low SSB | | S-08 | SSB Power (High) | ALC threshold for high SSB | | S-11 | FM Deviation | Sets FM modulation width | | S-20 | S-Meter Zero (No signal) | Adjust until meter reads S0 with antenna disconnected | | S-21 | S-Meter Calibration (S9) | Inject S9 signal (50µV) and adjust |