Zastone ZT-2R+

I don't know if the ZT-2R+ is truly an update to ZT-2R which is the Yaesu VX-2R clone. Here is a review of the ZT-2R+, but it doesn't offer any comparisons to the original. I will mention that Hans liked the original ZT-2R.


Description
The ZT-2R+ is one of Zastone’s newly launched miniature dual band, dual standby handheld wireless walkie talkies. With an aluminum housing, this hand held radio is shock proof and durable. With its anti-slip design, the grip is comfortable. With a 0.5-999Mhz wide band signal receiver, it is easy to hear communications coming through the walkie talkie. This ZT-2R mini walkie talkie can meet your needs, as it has over 1300 memory channels with sailing, shortwave and weather related channels. It easily supports HAM technology, making this a popular preferred product.

Main Features
1. Miniature dual band handheld transceiver
2. 0.5-999Mhz Wide Receive Band
3. Over 1300 memory channels
4. Sailing, shortwave, weather channel
5. CTCSS and DCS codec
6. Tone scan and independent tone mode
7. WIRES connection shortcuts
8. Rugged aluminum housing
9. Automatic Repeater Shift (ARS)
10. Dual tone multi-frequency
11. Automatic power saving
12. Busy channel lockout

General
Frequency Range	Wide Receiver Band List(RX List) BC Band 0.540-1.8 MHz SW Band 1.800-30MHz 50MHz Ham Band 30.000-79(59)MHz FM Band 76(59.000)MHz-108 MHz Air Band 108.000-137.000MHz 144MHz Ham Band 137.00-174.000MHz VHF-TV Band 174-222.000MHz Action Band 222-420.000MHz 430MHz Ham Band 420-470.000MHz UHF-TV Band 470-800(729).000MHz/(757-774MHz) Action Band2 800-999.000MHz(USA Cellular Block) TX & TX Frequency 144-146(148)MHz 430-440(450)MHz
Channel NO.	1300
Operating Voltage	3.6V
Temperature Range	-20°C~+60°C
Frequency Stability	±5ppm
Volume(mm)	47*81*23
Weight (g)	132
Transmit
Output Power	1/1.5/2/3W
Modulation	F3E
Spurious Radiation	< -60 dB
Adjacent Ch. power	< -60 dB
CTCSS/DCS deviation	< 5KHz
Audio Distortion	≤5%
SNR	>35 dB
Receiver
Sensitivity	0.18 uV - 3 uV
Adjacent CH. Sensitivity (W/N)	≥55dB
Audio Power	50 mW 100 Mw
Audio Distortion	≤5%
Intermediation	≥55dB

Standard Accessories：
ZT-2R+ Radio *1
3.7V 1500mAh Battery *1
Charger *1
Antenna *1
Back clip*1
Manual EN*1

Via Chinese Ham Radio Equipment on Google+

Baofeng UV-5R: Extreme Receive Modification

[ Don't have a UV-5R yet? Get one here. ]

Alvin and b1gslacker have been editing the .dat file to expand the receive frequencies of the UV-5R. As usual the results are a big of a mixed bag given the limitation of the hardware and software involved. Steve, WB8GRS, details the limiting factors:

"There are two components (the DSP and MCU chips) in the UV-5R that determine the band limits.

 1. The RDA1846 DSP chip is the chip that generates all the transmit and receive functions and it specifies the band limit as follows.

134 MHz to 174 MHz200 MHz to 260 MHz400 MHz to 500 MHz

This information is provided in the RDA1846 documentation in the file area. Many have reported the UV-5R will operate outside of these band limit on the 134 to 174 and 400 to 500 MHz bands (no one has reported any success using the UV-5R on the 222 MHz band), so my guess is the above band limits are not "hard coded" in the DSP chip, but are just guaranteed band limits and in fact some chips may operate outside these band limits to some degree.

2. The MCU which I believe is a custom version of the EM78P568-44 microprocessor tells the DRA1846 DSP chip what frequency to tune. If the MCU does not send the correct commands to the DSP chip the right frequency will not be received or transmitted. If for example you load in a 222 MHz frequency, the DSP chip is capable of receiving and transmitting on 222 MHz, but only if the MCU provides the correct commands to the DSP chip. If the MCU does not provide the correct commands, the display may should the correct frequency, but the DSP chip is doing nothing. Even if the MCU send the correct commands to the DSP chip, the RF pre-amplifiers and RF amplifiers external to the DSP chip are not designed to operate on the 222 MHz band so even if the DSP chip was commands correctly by the MCU, the power output and receiver sensitivity would likely be very bad."

b1gslacker gives the details of how to make the change here. The usual warnings apply - do this at your own risk.

"For those of you who would like to attempt to destroy your brand new shiny UV-5R, here are the instructions for "slightly modifying" CHIRP to accept frequencies WAY outside of the manufacturers recommended operating boundaries. These instructions are for windows XP only (but will probably work for others also)

1) Download the UV5R.pyc file in the files section.

2) Using your favourite zip utility (I recommend winrar) open the library.zip file located in your C:\Program Files\CHRIP\ directory (location may slightly differ based on your flavour of windows, but you get the idea).3) Delete the UV5R.pyo file from the zip4) Add the UV5R.pyc file5) Save the modified library.zip

I know that your thinking, but if you don't understand the instructions, you should definitely not be trying this, so don't even ask.

Now that you have installed the "ever so slightly enhanced" version of the UV5R CHIRP module you should be able to program frequencies between 10MHz-999MHz in the CHIRP application.
NOTE: Even if the radio accepts the frequency and displays it on the LCD display, this does not mean that the radio will actually work on that frequency (in fact we do know that there are definitely limits)"