Review – BTech AMP-25 series for Analog & DMR

by John ‘Miklor’

The  AMP-25  series  VHF / UHF Amplifiers

The recently announced BTech Digital and Analog amplifier series puts a whole new spin on mobile operation. It performs more like a mobile than it does a power amp. The D series are true TDMA Tier2 DMR amplifiers.

Note: This review was done using an Anytone D868UV on both DMR and analog.

In the Box

Included with the 40W Mobile Amp are:

–  Mounting Bracket
–  3′  Interface Control Cable (Kenwood K1 connectors)
–  3′  RF connect cable (SMA-M to SMA-F)
–  Microphone and Hanger
–  All necessary mounting hardware
–  User Guide

General Description
–  UHF or VHF Power Amplifier

–  2-6W  >  20-40W  Output

                         Modes of operation include:

             V25  U25             V25D   U25D
Analog (FM)
C4FM (Fusion)
P25  (Phase 1)
 >  DMR Tier II (TDMA)
 >  P25  (Phase 2)
Analog (FM)
C4FM (Fusion)
P25  (Phase 1)

A Different type of Mobile Amplifier

I found these to be much more than a typical power amplifier. Although they can function as a simple ‘In and Out’ power amp, this is about as close to a full mobile as you can get. Although the driving force was my DMR handheld sitting in my cup holder, the transmit audio was that of the included hand microphone and the receiver audio out was coming through the built in speaker driven by a four watt audio amplifier.

Transmit Power

I tested the power on two different models. The VHF V25 (non TDMA) and the U25D for UHF DMR.  The power was tested using the analog side of both into a calibrated Bird Termaline wattmeter. The maximum current drain from my 13.6V 30A power supply was just under 6A. This is low enough for the amp to be powered by the 10A accessory jack in your vehicle.


The basic frame measures 4.6″W x 1.3″H x 5.5″D (excluding the SO-239) and weighs in at 26oz.  I was curious to see the internal layout of the amp and to no surprise, there was a 5/8″ finned heat sink spanning the entire length and width of the case along with air vent along the back of the enclosure.

Operating Modes

These are single band amplifiers.
V25(D) = VHF 136-174MHz
U25(D) = UHF 400-480MHz.

Note: The V25D and U25D were designed to include DMR Tier II (TDMA) and P25 Phase 2 along with all other modes. Their operation varies slightly.

V25  /  U25
To operate VHF through the UHF (U25) amplifier, or UHF through the VHF (V25) amplifier, simply power off the amplifier. This will allow you to run straight through directly to the antenna without power amplification on that band.

V25D / U25D
These amplifiers will only operate within their specified VHF or UHF range. This is due to the circuit switching design of DMR Tier II and P25 Phase 2.

Hook Up

The simplest configuration is using the included RF cable to attach the radio to the amp. You could add a Spkr/Micr to the handheld, but you would still be bypassing some of the best features.

I use the two included cables. The 3′ RF cable to attach the radio to the amp, and the control cable. This allows me to use the full size hand microphone as well as connecting the four watt audio amp powering the speaker. The power included power cable is compatible with handhelds using the standard two pin Kenwood style connector, such as an MD380, D868, GD77, UV5R, F8HP, UV82, etc.

I use an Anytone D868 on DMR as well as analog with the hookup diagrammed below. Depending on your radios antenna jack, you may need to pickup an SMA-M to SMA-M adapter.



All channel selection and volume adjustments are done using the handheld. No duplicate programming or code plugs are necessary. Whatever is in my handheld is what I operate in the mobile

Operating my handheld in the low power position, I still get 22W out on UHF and my handheld’s battery life remains excellent, but high power gives me a solid 39W.


I was glad to see someone finally develop what is a full featured mobile amplifier capable of  DMR as well as all other modes including C4FM and D-Star that is small enough to mount in the car, boat, and on top of your computer. This amplifier is Part 90 certified and definitely worth considering.

Available from Amazon:    V25     V25D     U25     U25D

Digital / Analog
Mobile Power Amplifiers



Review – BTech UV-50X3 (Tri-Band)

by John ‘Miklor’

50X3combo-SFour years after its initial design, the VGC 6600PRO has evolved into the BTech UV-50X3, a full featured Tri-Band mobile that delivers a full 50W on VHF and UHF, with addition of a 220 MHz module that delivers 5W output.  The 220 MHz module was specifically designed and filtered for 222-225MHz US ham band operation.  I mention this as there are currently radios being advertised as Tri-Band operating in the range of 240-260MHz that are not adaptable to frequencies below 240MHz due to their internal filtering.

What’s in the Box

Included with the radio are:
–  Remote control head
–  Control Head Suction Cup Mount
–  18′ Separation Cable
–  Microphone with a 20 button keypad
–  Chrome metal microphone hanger
–  Metal mounting bracket with screws
–  Cooling Fan with Thermostat
–  Heavy Duty DC Power Cable (HD Auto Fuses)
–  Full 33 page English User Manual

50X3  Weight:  Main Chassis  2.1kg (4.6 lbs)
Chassis Size: 5.5″ x 1.8″ x 6.0″  (140 x 46 x 150mm)
Control Head: 6.3″ x 2.6″ x 6.0″  (157 x 66 x 33.5mm)


The 50X3 is FCC Part 90 certified for commercial use in the US.
Full specifications can be found HERE
Enclosure and Mount

The main chassis i
s a solid 4 lb heat sink with an added cooling fan. The chassis and cooling fan can be mounted either under the dash, or trunk mounted using the included 18′ control cable.  The radio is terminated with a standard SO-239 connector.

 50X3case-S  50X3mount

Control Head

The suction mount is about the best I’ve ever used. It requires a smooth metal or glass surface, but the silicon rubber cup will not let loose. My control head has been mounted atop my computer for over a month, and it is going nowhere.

The control head has two tuning knobs as well as two volume controls allowing the transceiver to essentially function as two separate radios in one package. The left can be scanning in the Channel mode while the right can be monitoring in the VFO.

The button functions are displayed on the LCD screen for easy function identification. The PTT button on the upper right is for Momentary or Toggle PTT. One press turns the TX on, next press turns it off. Setting to Toggle is convenient if running a net or using a mobile headset.



The radio chassis is one large block of heat sink that when testing takes forever to heat up. When it does, the 70 x 70 x 15mm cooling fan turns on. It’s very quiet and because of it’s size it’s very effective.

One of my main interests was the included 220MHz US ham band, as I have several Ham repeaters within 35 miles from my house. The power on 220MHz is rated at 5W, which I found was more than enough to reliably get into my local repeaters.  The signal and audio reports have been excellent.

I used my 13.8VDC power supply to emulate a standard auto battery. Running the radio at high power (50W) into a Bird Watt meter for 3 minutes showed no decrease in power or excess heat.

The 220 ham band transmit range is limited to 222-225MHz. The receiver is capable of being programmed above and below those frequencies, but may be outside of the performance range due to the ham band specific filtering.

Freq Low Mid High
146 8 20 50
222 5 5 5
446 10 24  55

HP 6580 analyser images


The radio comes with a full function keypad style microphone. On the right side are two slide switches that control the Lock and Lamp feature, and on top of the microphone are two frequency Up and Down buttons.  Along with a 16 button DTMF style keypad are 4 programmable function keys. Choices are Squelch Off, TX Power, Rptr Shift, Reverse, and Tone Call.

There are two microphone input jacks. One on the control head, the other on the main unit. There is also a built in microphone element inside the control head. Although the audio quality is excellent, the sensitivity is that of a standard microphone. The OTA reports were excellent with plenty of audio, so there’s no reason to shout.

A nice feature in the audio section is an adjustable microphone gain control. There are 5 settings available. Min, Low, Normal, High, and Max. Normal is great for speaking in a normal volume an inch from the microphone. Running a net with VOX and a headset, you can bring it up a bit. Driving in an off road vehicle, you just might need to set it back.



The UV-50X3 has two Double Conversion Super Heterodyne receivers, each with 500 channels, for a total of 1000 memories.

Along with the standard VHF / 220 / UHF frequencies, the receiver covers:

0.5-1.7 MHz   (AM Radio)
76-108 MHz   (FM Radio)
108-136 MHz  (AM Air Band)
137-250 MHz  (Ham & TV Band)
300-520 MHz  (Ham & General)
with a scan rate of 4 channels per second.

The control head has built in speakers, as well as one in the main module. An external speaker jack in the rear also allows for a larger speaker if desired. The jack provides for either mono or stereo output. (each receiver can have it’s own speaker). I found a menu setting to adjust the tone of the speaker as well. Although there is more than ample audio output, when the volume control is all the way down, the radio is silent, as it should be.

Cross Band Repeat

The radio takes full advantage of the independent receiver by including a Cross Band Repeat function.  I entered the VHF and UHF frequencies, power level and tones, selected the Cross Band mode, and was ready to go. The audio levels are preset and the audio quality reports were excellent.

Cross band repeating using a 220MHz frequency was not possible. This is more than likely a precaution due to the minimal frequency separation.


The control head has a large 5″ LCD with your choice of background colors. Options include White-Blue, Sky-Blue, Marine-Blue, Green, Yellow-Green, Orange, Amber, and White. The brightness and contrast are also menu selectable.



When you first attempt to program the radio manually, it may take a few tries to understand the flow of the menus.  After that, everything falls right into place. I’ve put together a programming flow to help assist with understanding the process.  All functions including the entry of 6 character Alpha labels can all be entered manually.


Unless you are only entering a few channels, I would recommend the optional PC05  programming cable. The UV-50X3 uses the CHIRP programming software.
Up to six Alpha Numeric characters (upper and lower case) can be displayed to identify each channel.

Scanning in the VFO mode allowed me to scan either the VHF, 220MHz, or UHF band.  In the Channel mode, the scan would select any channel in the list regardless of band.

Power Cable

The power cable supplied with the 50X3 is properly fused and will easily handle the current draw of the radio. This cable was meant to be connected directly to the battery or fuse panel.

There are radios that draw less power whose power cables use thinner wire, lower value fuses, and  can be plugged into accessory plugs. Do NOT use these cables, even though they may be plug compatible. The 50X3 draws twice the current, and will blow the fuses and possibly overheat the wire.

The cable on the 50X3 appears to match that of the hi-power Yaesu, Icom, Kenwood series.  ONLY use the proper cable for the radio.

Base Station Operation

The 50X3 draws upwards of 11-12A on high power transmit. A power supply capable of 15-20A continuous (not just surge) is recommended. Here are a few power supply Examples.

For mobile drive testing, I teamed this radio with a Nagoya Tri-Band  TB320A  and SB-35 NMO mag mount and the results were excellent.


The 50X3 has the power, functions and quality you would expect in an upper end tri-band transceiver.  It is based on a proven design, and I have found no issues with the radio over the past month. A bit more power on 220 would have been a plus, but it still gets me into the local repeaters fine.

Some of the added advantages to the US market are the FCC Part 90 certification, local US support, and exclusive program support using CHIRP software. The radio can also be shipped worldwide by contacting BTech directly.

This is definitely one of the nicest mobile transceivers I’ve used; and yes, I’ve owned the “big 3”.



More Information:

Review – Pofung (Baofeng) UV-82HP

by John ‘Miklor’ K3NXU

Not just a Power Upgrade
The new UV-82HP is not just a power upgrade, but a combination of all major features of both the UV82 and UV5R series in one package.

82HPWhat’s in the Box
– The UV82HP
– Newer upgraded A-V85 Antenna
– 7.4V 1800mAh Li-Ion Battery
– Upright Charger and wall-wart
– Manual written in English
– Belt Clip
– Hand Strap

The radio sports all traditional features of the UV82 design, with the larger keypad buttons and the zero at the bottom of the number pad where it belongs, etc.  It also is built using the latest generation chipset.

– The frequency range is the full  136-174.99 MHz, 400-520.99 MHz range.
– VHF output on the test unit clocks in at 7.3W with UHF at 6.0W
– The Dual PTT button is now an option that can be turned off. Previously only available with the commercial version (UV82C)
– Live On-the-Air audio reports are exc
– Alpha tags can be added with the required software below.
– The receiver sensitivity is still excellent.

So, What makes this version an upgrade?
– The original UV82 took a traditional UV5R, and added design features such as an upgraded case and Dual PTT switch. (comparison)
– Next came the UV82C which included options to synchronize the Dual PTT function to emulate a Single PTT, and the ability to lock out the VFO to prevent accidental field programming.
– Next came the 8W F8HP, the first of the high power Baofengs.
– An expanded feature added is R-Tone, a repeater tone for those requiring a 1000, 1450, 1750 or 2000Hz audible tone for access. This is not to be confused with CTCSS or DCS. Prior models provided Burst for 1750Hz only.

The UV-82HP now includes all of the above features in one package. The PTT synchronizing, VFO lockout, High Power, R-Tone, and newest generation chipset.

It has kept the traditional UV82 case design to ensure compatibility between all existing options, including Dual PTT Spkr/Micr, battery cases, holsters, battery eliminators, etc.

Feature UV82HP UV82 UV82C F8HP UV5R
High Power  7-8W Yes Yes
Dual PTT Yes Yes Yes
Single PTT Sync Option Yes Yes
VFO Mode Disable Yes Yes
Repeater Access Tones
    1000, 1450, 1750, 2100Hz
Yes 1750Hz 1750Hz 1750Hz 1750Hz
As mentioned above, with software, the UV-82HP can lockout the VFO mode to prevent accidental changes.
The Factory Software has been added to the  Software section.  The radio has also now included in the Latest Daily Build of CHIRP.
Note: A programming cable is required to run the software. Acquiring a quality cable is highly recommended. You will spend more time using the radio and less time trying to load special backdated drivers to your PC. A generic cable is less expensive, but a cable with an FTDI chip is Plug ‘n Play.
The UV82HP allows locking the PTT Button to simulate a Single PTT and override the Dual PTT feature.
Software Note
As you may have expected, running the UV82HP software will not activate or create new features on an older UV-82/82C.
All of my accessories for the standard UV82 are compatible, including the Dual PTT speaker/micr. With the exception of the battery and charger, all UV5R accessories work as well.
You can always run this radio in low/mid power to conserve battery, but when you need the extra power, it’s there.It’s nice to see a true upgrade of features to the UV82 series, and not just a fancy case or the addition of extra letters and numbers to the UV82 label.
A Feature Comparison published between the standard UV82 and its predecessor can be found at UV82_vs_UV5R
A full in-depth Technical Review of the Original UV-82 was done by Hans last year.
More Information:  CHIRP,, Review, BaofengTech

CHIRP Support now available for the new Anytone 8R series

By John ‘Miklor’ K3NXU

CHIRP, software that now supports over 80 different models of transceivers, isCHIRPlogo now providing basic support for the two newest models of the Anytone series, the TERMN-8R and the OBLTR-8R.  CHIRP’s Latest Daily Build can be found HERE.

The advantage of the basic settings is the “spreadsheet memory editor” which will allow owners to:
– import channels from a *.CSV file
– import channels from an *.img filexTERMN-LG
– copy-and-paste the stock config file
– load from external sources like RepeaterBook and RadioReference.

That is a BIG step and additional settings will be added in small groups.

Development of CHIRP is an all-volunteer effort and is offered as open-source software, free of charge. If you like CHIRP, please consider contributing a small donation to help support the costs of development and hardware.

More Information:  CHIRP,


Anytone Tech models, additional notes

Overall, reviewing these Anytones was a pleasant experience. After the reviews I looked into a few other things.

  • The batteries of the ANILE-8R (1300 mAh) and the NSTIG-8R (1800 mAh) are exchangeable.
  • The belt clips used on the ANILE-8R and NSTIG-8R are never a perfect fit. With the 1300 mAh battery there’s a gap (easy to lose a radio that way), with the 1800 mAh battery it’s too tight.
  • The antenna on the NSTIG-8R heats up fast at maximum RF output; the behavior resembles that of a Baofeng UV-5R stock antenna. The antenna appears to be reasonably efficient though. More tests are in order.
  • No such problems with the antennas of the ANILE-8R, the TERMN-8R or OBLTR-8R.
  • The NSTIG-8R, TERMN-8R and OBLTR-8R can display the remaining battery voltage. Measurements show that the radios are surprisingly accurate. If the radios say “8.1 Volts”, it really is 8.1 Volts. The ANILE-8R will round it down/up to the closest integer.
  • The TERMN-8R is difficult to use on SW because it defaults to 10 KHz steps. SW stations are 5 KHz apart, not 10 KHz. You can use the keypad to enter the correct frequency though. I had the bug confirmed by John; it’s now on the ‘to do’ list and will be fixed.
  • The more I had the TX audio compared by other hams, the more impressed I (and they) became.
  • There’s an odd problem concerning spectral purity with all x-band capable hand helds I reviewed. It only occurs when both VFOs are active; we (me and a few more knowledgeable RF lab gurus) are looking into that right now.