Guangzhou Chuanzhou Electronic Technology CZE-7C FM transmitter Instructions
- June 5, 2024
- Guangzhou Chuanzhou Electronic Technology
Table of Contents
CZE-7C INSTRUCTIONS
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 temperatures to use
- Please be sure to use complying with local radio regulatory agencies’ require
Product Features
- 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
- Stereo clear sound: the control panel consists of AT89C2051 and AT24C02; after the stage by two 2SC3355 and one 2SC2053 total of three power amplifiers to ensure that the three-dimensional sound quality output effect
- Good shielding: Structure design closely, not because of external signal induction frequency drift
- 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
- Easy to use: The 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
- 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
- This subsection is with a microphone and volume control
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 the 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 touching the key and the MCU controlling the internal PLL circuit to stabilize the transmission frequency. After two stages of power amplification, the transmitting frequency generates 800MW power input to 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.
Product Configuration
| NO. | Product name | specification | quantity | unit |
|---|---|---|---|---|
| 1 | Host machine | CZE-7C | 1 | piece |
| 2 | antenna | 1 | set | |
| 3 | Power adapter | DC 12V/1.67A | 1 | set |
| 4 | Audio cable | 3.5mm audio cable | 1 | piece |
| 5 | manual | e-instruction manual | 1 | copy |
Operating Instructions
Front panel and rear panel
front panel
| volume adjustment | Frequency down |
|---|---|
| volume input | Microphone input |
| turn on/of | Microphone adjustment |
| Frequency increases |
rear panel
The transmitter operates with an 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.
Audio volume and microphone adjustment
frequency adjustment
- 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:
- First press and hold the power switch【 】, and connect the power (DC 12V) to the antenna, after 3 seconds after releasing the key, at this time into the power adjustment status, the LCD display shows “L” or “H” (default image file H high power)
- Press【▲】 , and set it as high power (H)
- Press【▼】, and set it as low power (L)
- Select the desired power profile, and press【 】 .power setting finished, and it will into the frequency range setting state.
Frequency range setting
- After the power setting, it will enter the frequency range setting state, power setting is completed, press the LCD screen display shows a set of frequencies, the frequency data is the high-end of the operating band (below) (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
- 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 set is finished. (Note that the low-end band must not be higher than the high-end band.)
Product Technical Parameter
| 1 | Working voltage | 11-13V DC |
|---|---|---|
| 2 | Worknig current | 1.67A |
| 3 | Frequency domain | 87.9-91.9MHz |
| 4 | Frequency stability | +10PPM |
| 5 | Stepped frequency | 200KHZ |
| 6 | The operating temperature of the environment | 10°C—+50°C |
| 7 | Output impedance | 500 |
| 8 | RF power output range | H:7W (L:1W) |
| 9 | Harmonic and noise radiation | s-60dB |
| 1 | Audio distortion | <0.30% |
| 1 | Frequency response | 50HZ-15000HZ |
| 1 | Preemphasis delay | 50us |
1
3| Degree of separation| >35dB
1| Input level| s15dB
1| Modulation frequency deviation| ±75KHZ
1| SNR(Signal to Noise Ratio)| 60dB
1| Machine Size| 1289555mm
1| Machine weight| 269g
Common Troubleshooting
| NO | Undesirable phenomena | Reason |
|---|---|---|
| 1 | Can not be boot | 1)outlet for power; |
2)The power cord is plugged in;
3)the power adapter is normal.
2| A standing wave is greater| 1)The antenna is not connected;
2)The antenna does not match;
3)antenna installation location next to the reflector too
3| Transmitter distance is close| 1)feeder loss;
2)poor launch environment;
3)Output power is not adjusted;
4)antenna installation height is not high enough;
5)The antenna does not match;
6)receiver sensitivity
4| No power output| 1)Output power is not adjusted;
2)Machine standby or power.
5| Audio muting| 1)The master volume is not large;
2)the input audio signal is normal.
6| The microphone is silent| 1)microphone is normal;
2)the microphone volume is not large;
3)whether the microphone dynamic microphone;
4)microphone is plugged.
7| The soundquality is poor| 1)microphone quality is not good;
2)Input audio sound quality is not good;
3)antenna installation method is not correct;
4)audio signal or machine volume is not adjusted.
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:
- Problems caused by unauthorized disassembly or maintenance of Products.
- Problems caused by not following the operation instructions.
- Man-made damage/collision/collision/water and other problems caused Non – Product quality problems.
- The product is damaged by lightning or other force majeure.
- The product shell, Lion battery, microphone, charger, audio cable, charging cable, and other accessories are not included in the free maintenance scope.
For items beyond or outside the free repair period, we can offer very low repair costs.
- We provide lifelong maintenance for the products during free maintenance.
- We can repair the overdue or damaged products at a very low cost.
Disclaimer
NOTE: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:
- Reorient or relocate the receiving antenna.
- Increase the separation between the equipment and receiver.
- Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
- Consult the dealer or an experienced radio/TV technician for help
Changes or modifications not expressly approved by the party responsible for
compliance could void the user’s authority to operate the equipment.
This device complies with Part 15 of the FCC Rules. Operation is subject to
the following two conditions:
(1) this device may not cause harmful interference, and
(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
a minimum distance of 40cm between the radiator & body.
Please use this product following local laws or regulations about using wireless products, otherwise, the user will be responsible for any problems occurred by not obeying rules. We and our distributors are free of responsibility for that.