Antenna for walkie-talkie megajet 300. Automobile C-B antennas MegaJet. Main features and functions

Rating: 5 out of 5

Advantages:

Price quality Reception stability

Flaws:

Comment:

I bought this copy quite recently, took it from my hands for a penny.
Tested as a hospital, with a simple antenna.
The zone of reliable reception with a wire at the antenna input (ordinary wire) is 7 kilometers.
It's a pity that there is no normal antenna, but from experience I'm sure that it will confidently hold 20-25 kilometers. It is powered from 9 to 15 volts very conveniently with drops and low-quality power supplies. (Unless of course used as a hospital)

In general, I am satisfied, I think time will come in handy.

Rating: 5 out of 5

Advantages:

Convenient PTT, walkie-talkie is easy to operate

Flaws:

Not found

Comment:

Working in a taxi as a dispatcher, I worked on the Megajet. Excellent signal, switching to -/+ from the main channel. Magnetic antenna. On New Year's holidays, drivers wound tinsel around the antenna, which greatly interfered with signal reception.

Rating: 4 out of 5

Advantages:

Ease of setup and operation. Audibility during transmission / reception is good. Clarity of speech transmission. PRICE!

Flaws:

Noise reduction in automatic mode is very rough reception.

Comment:

I was going on a trip on the X-trail Vladivostok-Krasnodar and back. Read reviews, forums. I chose Megajet MJ-300 + Alan 145 cm on a magnet. I tuned it myself with a SWR meter. Got the hang of it very quickly. The trip was always included. Contacted subscribers to check the range of reception / transmission. On the plain, reception in normal weather conditions in summer is up to 10 km, transmission is up to 7 km., Hilly terrain and hills are different, reception is from 20 to 50 km (record) at the top and up to 3 km at the bottom, transmission is also from 700 m to 7 km. There is no more transmission range and no need! And the reception is also quite sufficient to slow down before an accident, traffic police, a camera, etc. It is better to choose manual noise reduction, on the border of interference, because automatic greatly coarsens the reception. Easy to operate and reliable. The second flight across the country with her. Only positive impression. There may be better, but it's enough for me. Tip: attach the antenna on the magnet in addition to the roof rails with clamps so that it does not move at all, otherwise the magnet (even through an elastic band) rubs the paint. I wanted to increase the power of the PRD, I disassembled it and determined that the assembly was Chinese. Don't worry - works great.

Rating: 5 out of 5

Advantages:

Price, quality, excellent reception

Flaws:

it is desirable to finalize

Comment:

I bought myself a Megajet MJ-300 about six months ago.
It attracted the following things:
1. Easy to control
2. Cost in stores and availability
3. Convenient PTT.
4. Inexpensive rework

I have long wanted to install a SVshka in my car in order to be aware of traffic jams, traffic situations, repairs, etc., and just kill time on a civil wave. Esteemed, thought - bought 300ku. The price is quite acceptable.

Antenna to her bought Alanovskaya on a magnet.
Connected without problems to the cigarette lighter: so, it seemed to me more convenient.
I screwed the antenna to the radio, pulled the cable into the trunk, put it on a magnet.
Then I screwed the PTT, stuck it in the cigarette lighter and Hurray! The radio works.
I immediately went to the long-range channel to test the radio and indulge in noise reduction.
Accordingly: the less noise reduction is strangled, the further it receives, but the more interference on the air.
In numbers:
1. Reception: with the noise reduction completely turned off, up to 10 km (provided, of course, that the transmitter has a good antenna). On average 4-6 in the city. With full reception, about 800-1400 m, but without a single interference.
2. Transmission: with an Alan 145 antenna, it shivers for 2-3 km in the city without problems.

This station is designed to solve completely different problems. Apparently, in this way, the RKK company decided to divide the market and earn even more money.

And I dare say they succeeded. The station is quite interesting, it is not designed to work in AM, although it can work in this modulation. Her path is frequency modulation, or FM.
So, if you're a CBS taxi driver, or you just use the band, mostly FM, and don't want to spend a lot of money on a walkie-talkie, this station is for you. In the harsh operating conditions of taxi companies, and it is there that the MegaJet MJ-300 is most often used, the station showed its best side. It is extremely simple and reliable. Now, let's take a closer look at it.

The station comes in a glossy silver colored cardboard box. Like the MegaJet, the cardboard is thin but strong.

The station is well packaged. Inside the box there is a plastic insert that absorbs shocks and is designed to divide the space for transportation.

The kit includes the radio station itself, instructions in English, a headset, a mounting bracket and fasteners.

Appearance
In appearance, the station is very reminiscent of MegaJet, the general pedigree can be traced well. The body dimensions remain the same.


The front panel is made of plastic. The plastic looks cheaper than . It is more slippery and glossy.


The case consists of a chassis to which all internal electronics are attached, two metal covers, top and bottom. Each cover is attached separately with 4 self-tapping screws. As I already wrote in, this is not very good, because at high volume such a design will rattle.


Ergonomics has changed. Now it is more convenient to use the station. The volume and squelch controls are still side by side, but they're now vertical, which I find more comfortable. The handles rotate with little effort, but gently, and without jamming. On the front panel there are buttons for switching channels, a button for changing modulation, a button for enabling channel scanning, this mode has been added here. The CH9 button performs many functions, which are described below.
The display, like that, has a pleasant amber backlight. The indication completely repeats the indication of the younger brother. Channel number, grid letter, modulation and mode 0/5 are displayed here.


The disadvantages of the display are the same. It is clearly visible only from the front and from above. You can't see anything from below.


The headset connector is modern 4-pin, looks reliable.


The headset itself is very simple, like that, it has only a microphone and a PTT.


The headset wire is also very soft and should not stiffen in the cold.

At the back of the station there is a connector for connecting an antenna, a jack for connecting an external speaker and a power cord.


There is no quick disconnect connector on the wire.

The speaker is located on the bottom cover, as in almost all civilian radios. There is also a marking plate with the serial number.

Functions
In general, the station repeats the functions of its younger brother, but there are some features. The station has 40 channels in normal mode, and 120 channels in extended mode. AM / FM modulation, work in zeros and fives (0/5), in addition, there is a channel scan function, which can be useful in unfamiliar areas, the function is displayed on a separate SC button. The main distinguishing feature is the presence of an automatic noise suppressor with manual adjustment. If sellers on the market will tell you that the station has a threshold noise suppressor, do not believe it! A real spektralnik, but with the ability to adjust, which is a plus.

To transfer the station to multi-grid mode, you need to turn off the station, hold down the A / F button and turn on the station. After a couple of seconds, you need to release the button and the display will show EP, which means that we have switched to multi-grid mode. Grids are switched by button CH9. The grids correspond to the following M - C, H - D, L - B. A total of 120 channels. The station has a built-in attenuator, which can be turned on if you hold down the CH9 button. The letters Lo (local on) will appear on the screen, indicating that the attenuator is on. To turn off, we do the same and LF (local off) should appear on the screen. This feature can be useful in noisy environments. To switch between fives and zeros, you need to turn off the station, hold down the A / F and CH9 keys and turn on the radio. The buttons should be released after a couple of seconds. The display will show the number 5 indicating that the station has switched to zeros. The scanning function will be turned on with the SC button. Scanning will continue until the squelch opens.

Inside
The station is made on a printed circuit board made of green textolite. Installation is neat, soldering flaws are not noticed. Not washed flux, too.


And the one in the photographs was left by your obedient servant during revision. I use a no-clean flux gel. The components on the board are not signed, which may make it difficult to find the right item.


Some of the parts are not soldered, which suggests that this printed circuit board is also used for the production of other radios. The output stage is made according to the classical scheme, on 2SC2314 and 2SC2078.


The overall impression of the filling is positive.

Declared characteristics

Frequency range: 26.965…27.855 MHz
Number of channels: 120 AM/FM
Transmitter power: 10W
Power: 13.8V
Dimensions: 138(w) x 40(h) x 125(d)
Weight: 600 gr

Modifications
About the improvements of the MJ-300.

Outcome
MJ-300, like, is not suitable for all tasks. They harmoniously divide the market and should be used in the niches intended for them. Due to the fact that the station has only one automatic noise suppressor, its use in the truckers' channel (15AM) is not advisable, since it will simply annoy you with its constant triggers that are not on the case. If they offer it to you for Channel 15, don't take it! For these purposes, a threshold squelch is most suitable, as, for example, in the MJ-100. The path of the MJ-300 is either working in a taxi, or using it for other tasks where frequency modulation is used.

Compact and inexpensive car radio CB range. This is the simplest, budget model in the line of radios made on the basis of the megajet 600 platform.

The features of both this model and the entire line include: a frequency synthesizer on a Motorola LC7152N chip (characterized by high stability, accuracy and purity of the formed subcarriers) and a SAMSUNG 3P9228AZZ-QZR8 digital control microprocessor. As a result - more stable and high-quality communication in conditions of high industrial interference.

This station is distinguished from other models assembled on the basis of the "platform 600" by its low output power, small LCD screen and compact dimensions - quite typical features of a budget solution. The walkie-talkie can be recommended as an inexpensive and reliable solution for a taxi or delivery service with a short range

There is a version of the Megajet MJ-300 Turbo transceiver, which is distinguished by an increased transmitter output power up to 18 W and the presence of an automatic spectral noise suppressor.

Megajet 300 radio stations are manufactured by several enterprises in Southeast Asia. The main external difference between walkie-talkies made in China is the blue backlight of the display.

Instruction for MEGAJET MJ-300 (in Russian).

MEGAJET MJ-300 FEATURES:

• Compact design
• Mode indication TX / SC / FM / AM / L / H
• Speaker with increased power up to 3 W (size 76x76 mm)
• Adjustable automatic squelch
• Scan mode (SCAN)
• Emergency tuning to emergency channel 9
• Ability to connect an external speaker
• AM / FM mode switching
• Button control of Up/Dn channels
• Channel display, grid, scan
• Connector for external speaker jack 3.5mm

Production - Republic of Korea (RKK company). Certified in Russia, 6 months warranty.

Equipment: radio station MEGAJET MJ-300, PTT with microphone, power cable, mounting bracket, instructions.

Mode - "45 channels": press and hold the A / F button for a couple of seconds - the screen will display the inscription SP and the radio will switch to 45 channel mode, when pressed / held again, it will switch back to 40 channel mode, the screen will display SF.

Switching Russian / European frequency grid in MEGAJET MJ-300: While holding down the A/F and CH9 buttons, turn on the radio with the VOL/OFF knob. The symbol "5" will be displayed on the screen. To return to normal mode, you must repeat the specified operation.

Turning on the attenuator: press and hold the CH9 button for 2-3 seconds, the screen will display the characters "Lo". If you press and hold the CH9 button again, this mode is turned off, and the symbols "L" will be displayed on the screen. An attenuator is used to dampen the received signal to improve speech intelligibility.