Rabu, 17 September 2014

Baofeng UV-5R (Steel Net)

Description:

UV-5R(Steel net) series two-way radio are the newest styles by BAO FENG, it has multi-functions, such as dual band, dual display, dual watch, its performances are excellent, the shape is fashionable, It has a good sales record in the communication market. It has been awarded the good reputation from our customers.
It has many colors which can satisfy different fashion fans
 It is really a cost-effective LCD dual band two-way radio,


Features:
1)      Output : 4W/1W
2)      Frequency Range: 136.00-174.00 MHz
                     400.00-480.00MHz
3)      Frequency Step Setting
4)      High &Low Power Switchover
5)      Battery Saving
6)      VOX Function
7)      Wide/Narrow Band Selection
8)      Auto-Back Light
9)      Dual Band Standby
10)  Time-out Timer (TOT)
11)  50 CTCSS and 104 DCS Codes
12)  Voice Prompt
13)  ANI Code
14)  PC or Manual Program
15)  DTMF Code
16)  PTT-ID
17)  ATUO Keypad Lock
18)  Busy Channel Lock Function
19)  Dual Band, Dual Display and Dual Standby
20)  Emergency Alarm
21)  Priory Scanning Function
22)  Relay Forwarding Confirmed (1750 HZ)
23)  Low Battery Warning
24)  U/V Cross Band Dual Watch
25)  Dimension: 110x58x32mm
26)  Packing Details:  40 Units/CTN,  Carton Size: 47.5x42x50 cm
                                       N.W: 21.5 KGS, G.W: 22.5KGS
 Technical Index

Frequency Range:       
136.00-174.00 MHz
400.00- 480.00MHz
Storage Channel
128
Step Frequency
2.5/5/6.25/10/12.5/20/25KHz
Rated voltage    
DC 7.4V
Frequency Stability
±2.5ppm
Work Temperature  
-20 to +60
Battery Capacity
H-1800m Ah (Li-ion Battery)
Battery Life
About 12 Hours
Frequency Combination   
PLL frequency synthesis
Antenna Impedance
50 Ω
Wok Mode     
Same Frequency  simplex Operation or Different Frequency  simplex Operation
Dimension   
110x58x32 mm (Excluded Antenna)   
                                                                     Transmitter
Output Power 
4W/1W
Modulation Mode(W/N Band)   
FM (F3E)
Maximum Frequency Deviation (W/N Band)
≤5 KHz
Spurious Power
≤7.5 µW
Adjacent channel power
≤-65dB/≤-60dB
Audio Distortion
<5 span="">
SNR
≥-45dB/≥-40dB
CTSCC/DCS Frequency Deviation(W/N Band)
0.7±0.1KHz (W), 0.4±0.1KHz (N)
Modulation Sensitivity 
8-12mV
Transmitting Current
≤1500mA
Receiver
 Sensitivity
0.20 µ V (12dB  SINAD)
Audio Power
1 W
Inter modulation Interference Resistance
≥65dB (W), ≥55dB (N)
Adjacent channel Sensitivity (W/N Band)
≥65dB (W), ≥55dB (N)
Audio Distortion
5 %
Receiving Current
≤ 380m A
 Note:
■ Specifications are subject to change for technology improvement without notice



Yaesu VX7R Triple Band 50/144/430MHZ Radio Transceiver

This is a great all-purpose radio. With coverage to tranmit on 6m, 2m, 1.25m and 70cm, you're almost guaranteed a repeater in range, and it even includes AM transmit and receive for 6 meters. It also has general coverage receive that can go up to 999 MHz. There are a few issues, some common to Yaesu and some specific to this model.

This radio can be confusing if you're used to a simpler radio. There are two VFOs - that is, you can monitor two frequencies at once. The two VFOs are different. The "main" band is the general coverage receiver, and you can enter any frequency throughout the radio's range, with the exception of US cellular frequencies, which are blocked. It doesn't matter, you wouldn't hear anything anyway, as cell phone transmissions are not only blocked, they are also digital and encrypted.

This main VFO sacrifices sensitivity in order to get its wide range. A scanner or multiband radio may have separate filters and mixers for each part of the frequency band, but the main VFO on this radio seems to have only one or a few, because any frequency entered into the main VFO will only be received very weakly. This includes the amateur radio bands. A local repeater comes in as an S9+ on the sub VFO, but only an S1 on the main VFO. This is a 440 band repeater with the stock antenna on an unmodified radio (we'll talk about that later).

The second VFO is called the "sub" band and only covers the 6m, 2m, and 70cm bands. That's not a typo, even though the radio itself can transmit on 220 MHz, it is not included on the "sub" VFO. This VFO tends to perform much better in the parts of the band where it works, which includes 50-53.990 MHz, 137-173.995 MHz, and 420-469.975 MHz.

Each VFO can be set in one of several modes: either frequency mode or channel mode, and either one or both can be set to scan. Scan works on either programmed channels or on a set frequency range, and when scanning channels you can set certain channels to be "preferential" - that is, included in the scan. As promised, this radio has a few "quirks" - one of them is that if you start the scan on a "preferential" channel, then only "preferential" channels are scanned, whereas if you start scanning on a non-preferential channel, than all channels will be scanned. And of course the "sub" VFO can only scan frequencies in the 3 above bands, so you can effectively have four different scan lists. You can also set a channel to be skipped, but I have not used that feature. Push to talk will halt scanning on the selected VFO.

Regardless of how it's set up, you can transmit from either VFO, and it seems to go through the same transmit hardware regardless of whether you choose to transmit from the main or sub VFO. At the very least, they perform equally well. If you try to transmit on a frequency outside the radio's band limits, you will get an error.

Programming channels from the keypad is completely possible, but it's easier to do it from the computer. The software, VX-7 Commander, is free. Buy the programming cable, it really is useful, even if you still program it from the keypad at least you can make a backup.

Here's another quirk: I set the local weather radio channel, 162.550, in both VFOs. When using only the main VFO, I get no signal. I switch to the sub VFO only, and get no signal. When I activate both VFOs at the same time, suddenly there is a signal S9+!

The weirdness of the two VFOs also gives other strange results. If I set the main VFO to scan my scan list, and then use the sub VFO to monitor an amateur repeater which is not on the scan list, then when the sub VFO is receiving, of course the main VFO continues to scan. As it does so, every time it switches channels (or maybe bands?) there's a slight click in the received audio. It makes it sound like the other station is transmitting from horseback.

If both VFOs are receiving different channels, then you will actually hear both channels at once.

There are hardware and software mods available to increase the transmit frequency range of this radio. Both are easy to do, but don't expect anything great - the transmit frequency will not go beyond certain hard limits, no matter what you do, and as you move further away from the design bands you get weaker transmit power, and if you try to work outside the sub VFO frequency bands you might actually be able to transmit to a repeater but be unable to receive.

The battery pack on this radio is tiny - about the size of two AA batteries - and accordingly it isn't very good. It claims 1400 mAh. Mine must be worn down - I bought the radio lightly used - because I get less than a few hours of use. Luckily the batteries are small, you can carry a few, but unluckily the batteries and chargers are expensive. The batteries each contain two 18490 Li-Ion cells at 1400 mAh and 3.7 V.