Dec 22, 2016 · The BFO circuit is a simple Hartley oscillator using a 455 kHz IF can. Output is delivered to a MOSFET amplifier. On the MOSFET amplifier, the bias to G2 can be varied by …

Feb 26, 2013 · 在LTspice中用两个bv电压源分别发生中频信号IF及拍频信号BFO，用第三个bv电压源作为理想乘法器进行拍频解调，后接两节RC低通滤波器，滤除音频以外的信号。

In a radio receiver, a beat frequency oscillator or BFO is a dedicated oscillator used to create an audio frequency signal from Morse code radiotelegraphy (CW) transmissions to make them …

Tune to a CW station on your receiver; Switch on the BFO; Adjust the BFO’s IFT core for a good audio beat-note in the Receiver. If the BFO is not oscillating, then reverse

Nov 19, 2024 · Si5351 PLL - provides VFO, BFO and 10MHz calibration reference. I.F. frequency set, real-time, via user interface. No need to recompile code when selecting or changing the …

You can fine tune your BFO injection level a couple of ways: The first way is by varying the G2 bias voltage from 6 volts (most gain) to 0 volts (shut off). Replace the 100k resistor from G2 to …

Mar 6, 2025 · The Progressive Communications Receiver from November 1981 written by Wes, W7ZOI and John, K5IRK provides 2 of my all-time favorite analog superhet circuits: The BFO …

A general purpose, discrete-component audio amplifier with selectable three or four pre-amp stages. Based on a design by Richard Andersen, KE3IJ (SK). Live a little . . . use something …

Fine tuning the impedance to the detector is accomplished by changing the resistor at the primary side of the transformer (50A01) in the BFO amplifier. Shown above is the "dead bug" style of …

May 7, 2008 · The 200pf capacitors between the LEDs and the crystals provide tuning of the crystal frequency so that switching between the crystal filters gives approximately the same …