Q & A
1. What is GPS and what is GPSDO?
GPS is the abbreviation of Global Positioning System in English, and the full Chinese name is Global Positioning System.
What we use daily is its positioning function, and another important use of GPS is timing.
GPSDO is the abbreviation of Global Positioning System disciplined oscillator in English,
The full Chinese name is the GPS Taming the Clock. That is, the time service function of GPS is used to adjust the clock to make the clock more accurate.
2. What is the basic principle of GPS tame clock? Why is it more accurate than atomic clock?
The basic principle of GPS taming the clock, using the standard time signal output by the GPS module, usually a second pulse (1pps),
To control or compare the frequency of the constant temperature crystal oscillator, and then output a signal to correct the frequency error of the constant temperature crystal oscillator.
Since the output of GPS signal has no accumulated error and the long-term accuracy is very high, the accuracy of the tamed constant temperature crystal oscillator is more accurate than that of the atomic clock.
3. Where are the more applications of GPS tame clock?
The most common is the base station of the mobile phone, which is used as the reference standard signal source.
4. Can I use it without GPS antenna?
It is not necessary to connect the GPS antenna, at this time GPSDO is equal to an ordinary constant temperature crystal oscillator.
5. How to place the GPS antenna, can it be placed indoors or near a window with glass, and what should I do if the GPS cannot be locked?
It needs to be placed outdoors, directly facing the sky, and not across the glass, because the glass attenuates the 1.5G signal greatly.
The antenna needs to be facing the sky, and at least 1/5 of the sky is required, otherwise the sky area is small, the GPS signal is poor, and the frequency accuracy is also poor.
GPS cannot be locked, mainly because the sky is relatively small. Choose to place the antenna in an open place. You can also put an iron plate on the back of the antenna to properly adjust the distance between the iron plate and the antenna to enhance the signal.
6. What should I do if the antenna is not long enough due to conditions?
You can add an extension cord, the author used an 8-meter extension cord in the test environment
You can also buy long GPS antennas, such as GPS antennas for boats, some up to 30 meters, 50 meters, and even up to 100 meters.
7. Can the GPS antenna be connected to the cable TV antenna at home?
No, cable TV does not have a 1.575G GPS signal.
8. How do I use the circuit board when I get it?
Connect the GPS antenna, the antenna is facing the sky, and the DC12V/1.5A power supply is connected, and the corresponding SMA port can output a 10MHz standard signal.
9. Is there any application in the HIFI field? Is it too mysterious to use in audio?
Very little, it can be said that there is no. It is not mysterious at all when used in the sound, the precise frequency, the sound detail is enhanced, the resolution is increased, and the background noise is reduced.
10. My DAC uses a frequency of 16.9344M, and your output is a 10M signal, can it be used?
It cannot be used directly, it needs a converter to convert the 10M signal into a 16.9344M signal.