This setting adjusts the master reference oscillator. Over time, or due to temperature fluctuations, a radio can drift slightly off-frequency.
The exact abbreviations in the service menu firmware can vary slightly depending on the firmware version, but they generally follow this layout: 1. Frequency Alignment (REF / FREQ)
Once in the service menu, you can navigate using the channel selector. While specific settings are not documented officially, community efforts have identified the core functions: 1. Frequency and Clarifier Alignment (TCXO)
This section controls the audio gain stages going into the transmitter. anytone at5555n ii service menu work
These represent the limit voltages for the .00 , .04 , .05 , and .09 frequency steps. Adjusting these allows you to precisely lock onto exact frequencies. 2. BFO (Beat Frequency Oscillator) Calibration (bfC)
The factory squelch on these radios can be aggressive. It often feels like "1" is too tight, cutting out weak stations, and "0" is too loose.
This guide focuses on the "Engineer" service menu, which offers granular control over RF performance, far beyond the standard user settings. This setting adjusts the master reference oscillator
: Significant changes to BFO or frequency alignment should ideally be done with a frequency counter or signal generator to avoid "bricking" the radio's performance.
| Setting | Function | Typical Value | Notes | | :--- | :--- | :--- | :--- | | | RF Gain Calibration | 86 | Adjusts receiver sensitivity. Do not adjust without a signal generator. Changing this value will also affect S-meter calibration . | | CH-51 AF RS3 | S-Meter Level Calibration (S3) | Varies | Factory calibrated to show S3 at a specific input level (-93 dBm). | | CH-50 AF RS1 | S-Meter Level Calibration (S1) | Varies | Factory calibrated to show S1 at a specific input level (-103 dBm). | | CH-40 to CH-49 | Various S-Meter Calibration Points | Varies | These settings fine-tune the S-meter readings at different signal strengths. |
The service menu is intended for technicians with proper calibration equipment, such as a frequency counter. Incorrectly adjusting these values can leave your radio unable to transmit or receive on the correct frequency. frequency targets for aligning the BFO in CW or SSB modes? Anytone 5555n Ii Service Menu - Google Groups Frequency Alignment (REF / FREQ) Once in the
The service menu is a hidden interface used for internal alignments like frequency offsets and RF gain levels. Accessing it requires a specific key sequence during boot-up, and because there is no factory reset for these internal values, it is critical to record your original settings before making any changes. Accessing the Service Menu
One of the biggest lies in a radio is the S-Meter. Manufacturers often calibrate these to flatter the user (making signals look stronger than they are).
To ensure your AnyTone AT-5555N II remains reliable and clean on the air, adhere to these operational guidelines:
Changing these values without proper test equipment (spectrum analyzer, frequency counter) can result in the radio transmitting off-frequency or causing interference on adjacent channels.
: Setting transmission power (TX power) too high can overheat and destroy the final transistors (MOSFETs).