User Instructions

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CZE-7C INSTRUCTIONS

1.Precautions for Use

●Ensure that the power supply voltage is within the extent permitted

●Maintenance can only be professional and technical personnel to operate

●Do not touch the antenna after the transmitter is powered

●Do not boot the machine before the antenna is connected

●Do not use in an explosive environment (such as gas stations, gas, steam, etc.)

●Do not place the transmitter in extremely dusty, humid, high temperature to use

●Please be sure to use complying with local radio regulatory agencies require

2.Product Features

1. High-fidelity high stability: Motherboard is adopted by next-generation integrated NC FM stereo

radio transmitter chip the BH1415 from Japan ROHM Company, built-in PLL frequency PLL,

audio pre-emphasis, limiter and low pass filter circuit to achieve high fidelity, high stability signal

transmission

2. Stereo clear sound: the control panel is consisted of AT89C2051 and AT24C02; after the stage by

two 2SC3355 and one 2SC2053 total of three power amplifier to ensure that the

three-dimensional sound quality output effect

3. Good shielding: Structure design closely, not because of external signal induction frequency drift

4. Excellent heat dissipation: The stability of the chassis using high quality aluminum alloy material,

lightweight and excellent heat dissipation can work continuously to ensure that equipment

5. Easy to use: Panel use LCD to display the transmission frequency, according to the identification

of the interface to connect to other hardware, easy to adjust and it is intuitive

6. Switching frequency: Can arbitrarily set from 87.9M to 91.9M range from 87.9M to 90M 90M to

91.9M, 87.9M to 91.9M

7. This subsection is with a microphone and volume control

3.Circuit Principle

Stereo audio via 3.5 mm interface input, after the adjustment of the potentiometer control

input to BH1415 internal, internal after pre-emphasis circuit, limiting circuit and low-pass filter

circuit and by 13, 14 feet again after access to the 7.6 MHz crystal vibration frequency

oscillation circuit through 200 points after the 38 KHZ subcarrier signal, and 38 KHZ

subcarrier by 2 points in the frequency of 19 KHZ pilot signal modulation.Firstly, the audio

signal and the 38KHz subcarrier signal are balanced modulated by a multiplexer to produce a

main signal (L+R) and a 38KHz subcarrier signal (L-R) modulated by DSB, and then the

composite signal with the 19KHz pilot signal is output from the 5th leg.The microphone audio

is also input by another 3.5mm interface, and after audio amplification, it is combined with the

composite signal output from the 5th pin. The two channels are directly modulated by a

high-frequency oscillator composed of a variogram diode.Frequency control by touch the key

and the MCU control the internal PLL circuit to stabilize the transmission frequency.After two

stages of power amplification, the transmitting frequency generates 800MW power input to

Summary of content (8 pages)

PAGE 1
CZE-7C INSTRUCTIONS 1.Precautions for Use ●Ensure that the power supply voltage is within the extent permitted ●Maintenance can only be professional and technical personnel to operate ●Do not touch the antenna after the transmitter is powered ●Do not boot the machine before the antenna is connected ●Do not use in an explosive environment (such as gas stations, gas, steam, etc.
PAGE 2
the final amplifier RD06, which generates about 7W power output. Then, after filtering out the frequency multiplier signal through a low-pass filter composed of LC, it is transmitted to the antenna for transmission.The MCU then transmits the current transmission frequency information to the user in real time through the LCD display module. 4.Product Configuration NO. Product name specification quantity unit 1 Host machine CZE-7C 1 piece 2 antenna 1 set 3 Power adapter DC 12V/1.
PAGE 3
The transmitter operate with a omnidirectional antenna and the output power of the transmitter is less than 10W, so it can be deemed to comply with the antenna requirements of 73.316. The antenna gain shall not exceed 2.5 dBi.
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 power adjustment The output power of the machine in two stages: High-power file (H): >7W; Low power file (L): <1W Turn off the power adapter, disconnect the transmitter power finish line state to follow these steps: 1. First press and hold the power switch【】 ,and connect the power (DC 12V) to the antenna, after 3 seconds after release the key, at this time into the power adjustment status, the LCD display shows "L" or "H" (default image file H high power) 2. 3.
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(2) (Factory default frequency is 91.9MHZ) For example, to set the operating frequency range of 90MHz to 91MHz, then through the key【▲】【▼】 , adjust the frequency data as 91.00MHz (3) Band after the completion of the high-end setting, press key【】, the band will enter the low-end setting, LCD displayed data band low frequency (below), through key【▲】【▼】to adjust the data to 90.00MHz Then press key【】, at this time the setting finished.
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9 Harmonic and noise radiation ≤-60dB 1 Audio distortion <0.30% 1 0 Frequency response 50HZ~15000HZ 1 Preemphasis delay 50us Degree of separation ≥35dB Input level ≤15dB 1 2 3 1 1 3 1 4 Modulation frequency deviation 5 1 ±75KHZ SNR(Signal to Noise Ratio) ≥60dB 1 6 Machine Size 128*95*55mm 1 7 Machine weight 269g 8 Common Troubleshooting  N O Undesirable phenomena 1 Can not be boot 1) outlet for power; 2) The power cord is plugged in; 3) the power adapter is normal.
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6. After-sales service Thank you for choosing our products, we will provide lifetime maintenance.We offer free repairs within 200 days of purchase.Except for the following: 1) Problems caused by unauthorized disassembly or maintenance Products. 2) Problems caused by not following the operation instructions. 3) Man-made damage/collision/collision/water and other problems caused Non - Product quality problem. 4) The product is damaged by lightning or other force majeure.
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(2) this device must accept any interference received, including interference that may cause undesired operation. RF Exposure Warning Statements: This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment. This equipment shall be installed and operated with minimum distance 40cm between the radiator & body.