1. Connect the antenna, and connect the antenna connector delivered with the machine to the lead of the external antenna. The machine delivers the SL16 connector. If you are in the urban area and the signal is good, you can connect a 2-meter antenna to the antenna connector. Left and right wires, stick out the window to receive FM radio. Of course, if you want to receive more radio signals, you must use an external omnidirectional outdoor antenna. The wiring method of SL16 connector can refer to the connection method of CCTV signal.

2. Plug in the power cord that matches the work of the machine, the machine uses 220V voltage,

3. Use the speaker cable to connect the speaker output terminal of this unit with your speaker input terminal. Connect two sets of speakers, it is recommended to use 4-inch to 8-inch full-range speakers for the best!

4. Turn on the power switch, the indicator light is on, wait for about 20 seconds to listen to the radio station. Rotate the tuning knob to select different radio signals. At the same time, the frequency meter will display the currently listening radio frequency. The green indicator bar of the tuning indicator tube will be tightly closed when the signal is the best.

6. After listening, turn off the power switch.

Tube FM Radio Instruction Manual
1. Circuit structure and design principle
This machine is a typical super-heterodyne radio. It adopts the design form of a whole circuit board design, including high-frequency reception, intermediate frequency amplification, amplitude limiting, frequency discrimination, stereo decoding, pre-amplification and other circuits. The output is a stereo signal. , can be connected to various types of tube power amplifiers, active speakers, stereo balanced amplifiers and other equipment. The specific circuit configuration is as follows: the high-frequency reception adopts the double triode 6N3 for high frequency amplification and mixer amplification, and the double triode 6N1 for the local oscillation. The intermediate frequency amplification adopts the two-stage pentode 6K4, and the two-stage limiter adopts the pentode 6J4. Phase discrimination, stereo decoding adopts LA3401, the decoded audio signal is switched by the switch and sent to the double triode 6N2 for 5 times pre-amplification, the output audio signal is sent to the power of two 6P1 pushed by a double triode 6N2 Amplifier, restore the sound through the speaker.
Second, the machine highlights
This machine has the advantages of light weight, high receiving sensitivity, using electronic tubes to receive FM signals, with a strong sense of nostalgia, sweet and mellow sound, using potentiometers and varactor diodes for tuning, which solves the need for air capacitors. The digital tube displays the receiving frequency, and adopts 6E2 to display the received signal strength, which increases the visibility and appreciation. The mesh cover design can avoid accidental burns by children at home. The panel is oxidized by CNC machining, and the shell is made of stainless steel by bending and welding. Reduced costs. The knob is also processed by CNC machining and polishing, which looks high-end and elegant. The circuit board of the whole machine is made of 2mm thick PCB, which increases the mechanical strength and is not easy to be damaged. The power amplifier part is installed separately and is easy to maintain.
3. Machine parameters:
Shell material: aluminum alloy + stainless steel. Receiving frequency range: FM87-108MHz
Power supply voltage: 198V-242V Number of channels: 2, stereo
Power consumption of the whole machine: about 100W Machine size: 374X240X140 mm
Net weight: about 8Kg Receiving form: superheterodyne
Output power: about 3W+3W
Fourth, the important components of the machine
Power Transformers,
tube,
high voltage filter capacitors,
Tuning the resonant inductor,
Varactor diodes, etc.