The requirements of the remote meter reading system for A-Crystal tuning fork quartz crystals:

Common meters include electricity meters, water meters, gas meters and heat meters.

According to the loaded module classification, the smart meter can be further divided into an IC card smart meter, a photoelectric direct reading smart meter, and a wireless remote smart meter.

The wireless 2.4G remote meter reading system adopts crystal oscillators, which are generally industrial grade standards. The main packaging standards are: HC-49SMD (11*3.8mm) and 4 pads crystal oscillator 3225 (3.2*2.5mm). The difference between the two is the 3225 package is oscillating output frequency of 1, 3 feet, 2, 4 feet are grounded, while for the HC-49SMD package no pin needs to be grounded; therefore, the application of the 4pads crystal 3225 is widely used.

The second is the use of DIP crystal package: mainly HC-49S (11 * 3.8mm) with two PINS, which cannot provide automatic tape packaging, can only be manually inserted and welded, and the labor cost is relatively high. Not normally mass produced, this product is generally used for research and development and initial experimental production, and the cost is low.

A-Crystal oscillators provide:

a stable oscillation frequency for the single-chip system, and is not affected by high and low temperature.

If the temperature drifts too much, it will cause a single-chip operation error, which will cause the whole signal system to be paralyzed and the meter's single machine to not work properly.

Manufacturers of smart meter products, in order to save costs, still use a large number of A-Crystal tuning fork crystals with specifications: Cylinder type,DT206,2*6mm,DT cut, frequency:32.768KHz, Load Capacitance:12.5pF, Frequency Tolerance(at +25℃): +/-5ppm, Operating Temperature Range: -20℃ to+70℃.