Q6: Why do most frequency generator manufacturers limit their audio frequency modulation to 20,000 Hertz?Ī: Most likely they just did not want to spend the money to build the circuit with a higher capability. It produces harmonic sidebands replicating the output of the 1930's, 1940's and 1950's M.O.P.A. The GB-4000 goes beyond what most carrier frequencies are designed to do. So, the RF carrier frequency is the means by which the radio station transmits the signal through the air to you the listener. Modulation is the mixing of the RF carrier frequency with the audio frequencies. The GB-4000 has a frequency range from 1 to 20 million Hertz (20 Megahertz).Ī: Any radio station uses an RF carrier frequency to carry or modulate (piggyback) the audio frequencies, voice or music that is sent out for you to hear on your radio. Q4: Can the GB-4000 frequency machine output RF or Radio Frequencies.Ī: Yes. This method is now the standard in the industry.
No old antique frequency generator has the frequency accuracy of today’s modern equipment. By this method we have all the harmonic content of the old antique vacuum tube frequency generators along with the digital accuracy. These frequencies are phase-locked-looped for perfect accuracy. The frequencies are output from a DSP, (Digital Signal Processor) then go through the DAC and then through a low pass or band pass filter and come out converted to analog. This type of electronic circuit is used in all modern analog frequency generators. Q3: How does the GB-4000 frequency Instrument output its frequencies analog when they come from a digital DSP chip?Ī: The GB-4000 uses a DAC (Digital to Analog Converter). It also uses digital frequencies output from a DSP (Digital Signal Processor). The GB-4000 also goes beyond using crystal-controlled frequencies. Q2: Does the GB-4000 use crystal controlled frequencies for high accuracy.Ī: Yes it does for the 3.1 MHz RF carrier frequency. Q1: Does the GB-4000 output its frequencies digital or analog?
GB-4000 Frequently asked questions and answers………