Spectrum analyzer is something RF specific, and is a necessary testing tool in our remote control factory, because it shows three most important characteristics of remote control signal, the frequency, the signal strength and wave form.
The most important factor to customer is how long distance the remote control can operate, obviously the more precise center frequency, the higher signal strength would help, but you may wonder what is wave form, and how does it affect the remote distance? from spectrum analyzer we can see the correct wave form is always better look, smooth and continuous, and the space below the wave would be as clear – dark as possible, no un-necessary lines between. While the worse wave form would always look like shattered.
Even if the signal strength is high and frequency is correct, the remote distance might be lower because the signal is not correctly encoded into radio waves or carried out by transmitter, this is sometimes the most tricky part we have to deal with in manufacturing and testing process.
Oscilloscope is pretty much a basic tool in electronics, and can pick any voltage change in certain circuit point. Although we don’t need oscilloscope in remote control manufacturing and testing, it is most helpful in development process. Since today’s remote control has all kinds of encoder format, fixed code chip such as PT2262 / eV1527 are less and less used, while HCS301 rolling code chip or even more customized chip programmed using microcontroller is more and more widely adopted. Oscilloscope is a very useful tool in locating / reading and verifying the output data either from transmitter or pickup by receiver part.
We will have a seperate post focused on data format reading using oscilloscope of a typical rolling code chip Microchip HCS301 Keeloq encoder.