A LONG-RANGE, OVER-THE-AIR RADIO WAVEFORM ANALYZER
A LONG-RANGE, OVER-THE-AIR RADIO WAVEFORM ANALYZER
AFC Meter
AUTOMATIC FREQUENCY CONTROL METER
Most land mobile radios utilize embedded technology, such as Automatic Frequency Control (AFC) or Automatic Fine Tuning (AFT), to temporarily correct frequency misalignment or errors.
LocusUSA’s patented technology can measure the amount of AFC correction applied to a subscriber radio in real-time, even while it’s active in the field. The DiagnostX AFC Meter captures and analyzes control channel transmissions to evaluate these temporary adjustments.
Standard Now: The AFC Meter Feature in All DX-2002 Series Instruments and NX-200 Remote Receivers
AFC Meter
AUTOMATIC FREQUENCY CONTROL METER
Most land mobile radios incorporate an embedded technology that aids the radio in adjusting frequency misalignment or error. This temporary correction is known as Automatic Frequency Control (AFC) or Automatic Fine Tuning (AFT).
LocusUSA has developed a patented technology to determine how much AFC correction is applied to a subscriber radio in real-time while the radio is active in the field.
The DiagnostX AFC Meter measures the temporary AFC adjustment by capturing and analyzing all control channel transmissions from the radio.
DiagnostX AFC Meter Explained
BENEFITS
DiagnostX evaluates radios using specific metrics, including Frequency Error. Sometimes, a radio may appear within spec, but the AFC Meter shows how much automatic frequency control is correcting the error. This temporary correction can be up to 1000 or 1500 Hz, depending on the manufacturer. Misaligned radios will struggle to connect to the system, and as alignment worsens, AFC will stop working, leading to a failure. Even if a radio seems fine temporarily, it may need maintenance. The AFC Meter, the only tool for identifying such issues, provides a report on AFC engagement by radio ID.
DiagnostX AFC Meter Explained
BENEFITS
DiagnostX provides an evaluation of the radio based on specific metrics, including Frequency Error. Sometimes a radio will show as being within spec according to pre-set DiagnostX thresholds. The AFC Meter will display how much AFC is being engaged. This means that there is a temporary correction of Frequency Error of up to 1000 or 1500 Hz depending on the manufacturer. A radio that is extensively misaligned will experience issues connecting to the system. As the radio continues to drift further out of alignment, AFC will no longer engage, resulting in a hard failure. A radio like this, even while temporarily appearing to be within spec, is a definite candidate for maintenance. The AFC Meter, the only tool available for identifying such radios, provides a report of AFC engagement on all measured subscribers, listed by radio ID. The AFC Meter is an add-on feature to the DiagnostX system.
TECHNICAL BACKGROUND
Radios contain crystal oscillator circuits that can drift over time. These crystals are affected by factors like voltage, aging electronics, battery power, temperature, environment, and mounting conditions, leading to detuning and communication degradation.
This is where Automatic Frequency Control (AFC) comes in – it temporarily controls and corrects the oscillator drift of a two-way radio until it is turned ‘off’. AFC works within limits to address these variables, hiding the underlying issue until communication failure occurs.