Weather Conditions | Dedicated to the relevancy & growth of electronics, maker & amateur radio hobbyists in the Hudson Valley

Monday, September 17, 2018

Review: N5BOC Duplex Hotspot Board

Quality of construction has proved important across all newer digital voice capable radios and related infrastructure.

Modes such as DMR, NXDN and P25 all require stable clock sources to ensure proper operation with DMR especially requiring this because of its capability to allow two simultaneous data or voice streams on the same frequency at the same time. 

As the old adage goes, "You get what you pay for" holds especially true for the most modern of amateur radio equipment.

MMDVM raspberry pi zero  duplex texas lone star
David Dennis N5BOC has created a high quality small duplex MMDVM board for use
with the Raspberry Pi Zero or any of the larger Raspberry Pi too 

This review provides some observations on the N5BOC designed duplex multi-mode digital voice modem (MMDVM) that packs a lot of capability into a very small form factor.

The key benefits of buying the N5BOC duplex board compared to the foreign manufactured ones are as follows:

  • Gold plated contacts for superior on-board connections
  • Thicker PCB material for improved DC and RF stability
  • Additional u.FL connectors for external "pigtail" connections
  • ECS branded TCXO for very stable frequency operation (No offset likely required)
  • 1/2 the size of foreign made duplex board
  • Lower power consumption compared to foreign made duplex board
  • Help support domestic US amateur radio community design talent
Further details about why David Dennis designed this product, his design goals and user manual can be found HERE.

This MMDVM duplex board is handmade in small quantity to ensure quality. They sell out quickly, so be
sure to get on the waiting list and purchase it as soon as they become available.

After creating a fresh Pi-Star image and setting up both time slots with active talk groups such as 91,310, 3100, etc and running it this way for an entire weekend on a 16000mAh power bank, here is what was learned.

Feedback #1: Running the N5BOC board on a Raspberry Pi Zero lasted 11 hours longer compared to using the foreign pictured duplex board with identical rechargeable power sources down to 50% battery capacity.

getting started MMDVM hotspot
Comparing the N5BOC duplex board to foreign duplex board

Feedback #2:  No offset was required on the N5BOC board compared to the pictured foreign board.  Better design and material likely attributed to this. 

Feedback #3: The N5BOC board is well thought out and designed compared to the single sided and less complex foreign board options

Critical Comments:  It is hard to find something to complain about with this product because all the underlying concepts are not new to me, but I would like to see:

What? User install-able SMA connectors for different mounting options and use of u.FL connectors instead which are great to see included.
Why?  Some people may not have good de-soldering skills and may want to use "pigtails" instead.
What? J3 connector placement for an OLED display if installed will block the on-board status LEDs 
Why? No big deal, but some may get annoyed by that. Good reason to consider other display mounting options or even a "wireless" display or just block out the LED by adding a display over the top anyway which can be turned off in software more easily then LEDs.

Connector pin out description for N5BOC duplex board

Final Comments: For the current price of just under $100, this is a very good piece of engineering. My current fully enclosed duplex board looks like an ancient prototype compared the smaller N5BOC board and am looking forward to an official case or creating something of my own.

Will the N5BOC duplex board look as cute when it gets an enclosure?

Friday, August 24, 2018

MMDVM Firmware, why update? How to update!

Have you heard "ham radio" people talk about updating the firmware of the MMDVM boards and wonder, should you?

The general opinion is "Always move up to the latest level", which is fine for early adopters that really know what they are doing or pretend to at the very least.

help with mmdvm pistar upgrade

An experienced voice will say "Stick with the version that is working and only move up if there is a feature you really need or want".

That is the best advice we can give, stick with what it working and ALWAYS read the firmware build notes as to what it delivers before applying it. 

Good news! The MMDVM firmware is open source! 

Unlike many radios, you can read about all aspects of the code at:

Where can you see the latest notes on MMDVM Firmware?

Here is the build log to see what each version delivers:

  • Fix D-Star reliability with low RSSI signals (transmission lost recovery)
  • Fix for missing POCSAG start tone and incomplete messages
  • Receiver gain options (only custom firmware builds)
  • Additional NanoDV boards support
  • RAM memory optimization
  • Fix small bugs
  • Add support for POCSAG
  • Fix LEDs bug and minor bugs (thanks Flo DF2ET)
  • Reducing YSF, P25 and NXDN buffer sizes to fix RAM limit bug in duplex mode
  • Add binary firmware support for generic MMDVM_HS boards with serial interface
 v1.3.6  (Very stable, most boards shipped with this)
  • More space for ring buffers
  • Pseudo random fill instead of 1.2 kHz fill for DMR DMO
  • Support for MMDVMCal
  • Deviation adjustment for each mode in MMDVM.ini
  • Default RSSI support for MMDVM_HS_Hat
  • Support for MMDVM_HS_DUAL_HAT board
  • Support for Nano DV board
  • Optimizing program size
IMPORTANT NOTE: Please set all TXLevel parameters to 50 % in MMDVM.ini in order to use default deviation levels.

What MMDVM boards are we talking about?

You need to know which board you own!

Look it up on google and match the image with what you have.  Do not just assume saying "Version 1.0" is the same for everyone.

Also, you will need to know what TCXO also known as a "crystal" is on your board. (14.xxxx or 12.xxxx MHz)

Once you know that you can flash your board from the PiStar command line ( "http://{address of your PiStar}:2222 login" with pi-star as the user name, if you did not change the password the default is raspberry )
  • ZUMspot RPi board
    sudo pistar-zumspotflash rpi
  • ZUMSpot duplex board conected to GPIO
    sudo pistar-zumspotflash rpi_duplex
  • ZUMspot USB dongle
    sudo pistar-zumspotflash usb
  • ZUMspot Libre Kit or generic MMDVM_HS board with USB
    sudo pistar-zumspotflash libre
  • MMDVM_HS_Hat board (14.7456MHz TCXO)
    sudo pistar-mmdvmhshatflash hs_hat
  • HS_DUAL_HAT board (14.7456MHz TCXO)
    sudo pistar-mmdvmhshatflash hs_dual_hat
  • MMDVM_HS_Hat board (12.288MHz TCXO)
    sudo pistar-mmdvmhshatflash hs_hat-12mhz
  • HS_DUAL_HAT board (12.288MHz TCXO)
    sudo pistar-mmdvmhshatflash hs_dual_hat-12mhz
  • Nano hotSPOT board
    sudo pistar-nanohsflash nano_hs
  • NanoDV NPi board
    sudo pistar-nanodvflash pi
  • NanoDV USB board
    sudo pistar-nanodvflash usb

An example: Updating a Chinese JumboSPOT"

So this is the board I (Joe N1JTA) bought from eBay awhile back:

I then soldered on the pins to enable FW update (Please see my past article "MMDVM JumboSPOT board: Mods you may need"

Also you can see the TCXO at X1 which under magnification shows it the 14.7456MHz TCXO. Thus this board is the "MMDVM_HS_Hat board (14.7456MHz TCXO)"

Before doing anything backup your PiStar settings via: http://pi-star.local/admin/config_backup.php

It's actually quite painless, that is if you don't mind the good old command line! First login in to your PiStar HotSpot's terminal: http://pi-star.local:2222 aka http://{your pistar ip address}:2222

Recall that the Default User name: pi-star and Default Password: raspberry that is if you have not changed it ( I recommend changing the password )

Login then run:
sudo pistar-mmdvmhshatflash hs_hat
Yes it's that easy! The command will find the latest build of hs_hat download it and apply it to your JumboSPOT.

Please note you MUST have connected the Firmware pins of your JumboSPOT to your Raspberry Pi for the flash utility to work. That is the above command will fail if your board does not have it's FW pins connected ( please see MMDVM JumboSPOT Mod you should know )

Advanced: Build FW from source, the easy way!

The normal WARNING! you are responsible for your hardware! Don't do this if you are afraid of messing up your critical infrastructure. Well if you mess up you can always flash with the commands above to recover.

Please note that this site only will build the generic hs_hat for single and dual time slots. Now you can use this handy web page to chose what features you want to turn on or off!

A must have for me is "Constant Service LED once repeater is running" so once Pi-Star comes online the modem will NOT blink it's green LED. If you work near your hotspot that dang blinking light can be annoying.

Once you chose all the features you want in your FW then click "Submit" when done it will open a download. You can save a copy on your PC if you like. Under the download section it will provide you a link to the bin file. Thus at the Pi-Star command line you can do the following:

pi-star@dual-mmdvm(ro):~$ rpi-rw
pi-star@dual-mmdvm(rw):~$ wget

You should see a message about ‘mmdvm_f1.bin’ saved

pi-star@dual-mmdvm(rw):~$ sudo pistar-mmdvmhshatflash-custom

Make sure pi-star is in write mode. Not only will the download fail but the fw flash will also fail.

What did you think?

Constructive comments are always welcome. Thanks! 

Wireless Nextion Display You Say?

When I started tinkering with the JumboSpot and small OLED displays, it got me interested in larger and informative display options, so I quickly picked up a few Nextion style displays as covered a few months ago in the "Bigger Display for Jumbo/China/Covert" article.

Even though having a larger and more informative display to be used with the MMDVM based hot spot is great to show callsigns, name, location, IP addresse, temperature, etc, that means the hotspot can not be put where I want the hotspot for maximum RF range and still see the display.

Be sure to purchase a Nextion display and not a TJC branded one. Only the Nextion version has English development software. TJC screens are designed for the China market or those that can read Chinese software. Otherwise, they are the same thing and would work fine with any MMDVM Pi-Star Hot Spot

So, what about making the display itself remote from the actual hot spot?  Seemed like a good idea and here is what I have done to make this a reality.

Wireless Nextion Display

Getting the correct signal from the hot spot was easier than I thought after some research and decided instead of trying to send the signal over wireless serial blue-tooth connection to a remote receiver that feeds a Nextion display that using 70cm amateur radio spectrum would be just be a bit more fun to experiment with.

Silicon Labs is just one of the companies with components
that make this small data transceiver module a reality

Inexpensive HC-12 modules allow serial based communication over a wide range of speeds and can be configured to operate on a number of predefined channels set by the manufacturer or configured by the end user. Here is a great user manual I found on the Elecrow website that will fill in some of the blanks on its capabilities.

The HC-12 can be driven from from the TXD, GND and VCC pins on the duplex or semi duplex hot spot boards easily.  All I needed to add was a 1N4007 diode to drop the voltage a little in order to not over drive the HC-12 module since its sensitive to over voltage.

Since I was not interested in providing a two way wireless connection, there was no need for the RXD connection between the hotspot and HC-12.

Steve K2GOG SDR capture of MMDVM DMR audio and HC-12 pulses

After getting everything connected, crossing my fingers and apply power, I started to see pulsed signals being sent on the default HC-12 module frequency of (3) 433.400 MHz as shown on the screen capture by using an inexpensive SDR dongle sch as the NooElec Nano3 and the popular SDR# software package.

The other two signals shown is the output or transmit signal generated by my duplex hotspot that was connected to the HC-12 and was set to operate on (1) 432.525 MHz, only 875 kHz away.

The very narrow continuous unmodulated signal at (2) 433.063 MHz seems to be coming either from my cable modem or cable line, but does not seem to be an issue I can easily fix, so just ignore that.

Within the Pi-Star dashboard, I selected screen type as "Nextion", port as "Modem" and Nextion Layout as "ON7LDS L3" since that is what I use with my 4.3 Inch Nextion display that runs a modified version of one of the nice layouts found in the file section of the Nextion Ham Radio Screens Facebook Group

Connecting the HC-12 module to the Nextion display was a little more tricky to receive signals though.  I connected the RXD and GND from another HC-12 to the Nextion display and ran +5V to power up the display.

I needed an isolated power supply with another 1N4007 diode to power up the HC-12.   Everything worked on the second try!   The first try was when I accidentally forgot to use a diode to drop the voltage and "smoked" an HC-12, but that is why I ordered a few spare just in case!

On the second try I thought I had a different issue, but as it turns out the default setting of the HC-12 is pretty high transmit power and I recall the manual saying to separate modules by a few feet.

Once I moved the contraption across the room, my display was updating with users chatting away on TG 91 worldwide DMR talk group!

An Additional Future Experiment

Here is where I hope to get some people interested and assist with an extra added feature/benefit.  What about decoding the data packets that the HC-12 transmits by using the SDR?

Its possible to decode weather stations, door bells and other 433 MHz range devices with the rtl_433 application when used with an SDR dongle, so maybe someone can find a way to translate the pulses and view those on a computer or smartphone connected to an SDR?

There are likely many protocols that an HC-12 can send and receive, so why not figure out a way to add another to read what the Nextion display expects to see and render that in some sort of application.

It is easy to record and playback "spectrum" with SDR#. To play back the file related to this article, instead of  selecting your own SDR device in the menu drop down, select "IQ File (*.wav) and navigate to where the base-band recording downloaded here was saved to. Then press "Play" and be amazed! 

To get anyone (and everyone) started, I did a base-band recording that can be easily played back in SDR#. You can play back the file as if you were in real time listening to the signals sent by the Nextion. Its even possible to use DSD+ to decode the active DMR audio signal too! 

Caution:  Using DSD+ can be daunting, so look elsewhere on getting that to work.
This way you can know who is speaking to match it against the pulses sent by the HC-12. The pulses will show call sign, talk group and DMR ID to whom ever can decode it so you know what sort of information to look for in the packets.

Just 37 seconds of 2 MHz wide of spectrum took up 225MB, so I have it hosted on Google Drive.

The First HVDN Contest

If you can make some progress, share your tips in the comments below or send a private email instead via one of the HVDN contact forms.   

First maker, hacker, ham, etc to make MAJOR documented progress, Hudson Valley Digital Network will reward your efforts with an HC-12 and an RTL-SDR device, so ready.....set..... 01000111 01001111 00100001

Thursday, August 23, 2018

Improving the TCXO for Duplex MMDVM Hotspots

Various MMDVM hotspot devices have been on the market for about 3 years now and only recently have there been duplex ones available, which create more capability but with more complexity.

Proper passive and/or active cooling is a must when it comes to proper
operation of the duplex hotspot devices currently on the market.
Pictured device was constructed by Steve K2GOG

This HVDN article will explore making some thermal improvements to the duplex MMDVM boards that have become widely available over the past few months and are replacing many of the older hotspot devices available over the past few years.

The TCXO is one of if not the most critical part on the duplex
 hotspot device that creates user satisfaction

Problems and Corrections For Duplex MMDVM Hotspot Operation

TDMA based modes such as DMR are very reliant upon very stable time references. In order to create the simultaneous TS1 and TS2 capability, the TCXO needs to be extremely stable and quality components are only part of the equation.

If a Raspberry Pi 3 or 3B+ is to be used with many of the duplex hotspots, its important to do the following:

More Power: Ensure you are using a 5V 2.5A continuous or higher power source. Your RPI3B+ draws enough current and when coupled with the duplex board creates a higher load.  You need ample enough current to ensure stable operation.
Remove Heat: Placement of the MCU on the Raspberry Pi can create enough heat that will rise to the bottom of the Duplex MMDVM board which can influence its stability. You must use a heat synch or heat spreader accordingly to keep temperatures stable and as low as possible. These techniques are often known as passive cooling.
Move Heat: If it is not possible to remove heat, you can move it by using active cooling through the use of a small fan.  If choosing this route for heat management, consider the current impact this may have on your power supply.

Passive cooling through the use of self adhesive heat
spreaders on the bottom of the MMDVM duplex board

Appropriate Enclosure:  Do not choose to mount your assembled RPI3B plus MMDVM Duplex hotspot in a plastic, Plexiglas or 3-D printed enclosure. This enclosed and insulated enclosure may limit the life of your hot spot as well as impact its overall performance. Consider a metal or open frame construction if there is no option for active cooling available.
Proper RF Grounding & Shielding: Proper selection of antennas and installation of the SMA connectors is important to top performance of your hotspot.  Selecting the correct frequency that will best perform with your antennas and characteristics of your MMDVM device are important. HVDN recommends using frequencies in the lowest part of the 70cm allocation in your country for transmit as well as receive with appropriate spacing and separation.

Inside of Steve K2GOG's passively cooled duplex hotspot. Changes include extended SMA antenna
connectors to pass through the top of metal vented enclosure, passive heat spreaders under the
TCXO and directly above where the MCU is directly underneath the MMDVM board.

Correct Firmware:
 The development teams that create the hardware and software constantly make revisions based on user feedback. As of the August 22nd 2018 revision, improvements for TCXO management have been included in the firmware and it is advised for users to upgrade to atleast FW. 1.4.7 to take advantage of this. Here is a good article on how to update the firmware by Joe N1JTA

If you choose to use the Raspberry Pi Zero series of single board computer, many of the heat related issues are not much of an issue.   There is only one duplex board available that has a similar footprint as the RPIZW and is made by N5BOC and is available for purchase on Tindie, but HVDN has not yet been lucky enough to get one just yet for testing.

The N5BOC  duplex board is the smallest and most stable hotspot
device on the market capable of dual time slot operation

To learn more about some of what has been discussed in this article, here are some additional links:

Monday, August 20, 2018

Firmware Update: TYT MD-UV380/390 Update 17.05

The TYT MD-UV380 and waterproof UV390 has just seen its first firmware update since many people first started taking shipment of this new VHF/UHF dual band dual mode (FM/DMR) hand held radio in April and May 2018.

August 2018 Firmware Version 17.05

Users of the non-GPS enabled MD-UV380 first started to report having the 17.05 firmware loaded back in July, but this update was nowhere to be found on the TYT website until August 20th 2018.

This latest firmware release has multiple versions explained below in this article.

latest md-uv380 firmware
TYT MD-UV380 Firmware Update Version
17.05 Released on August 20th 2018 is now available on the TYT website 

If you were one of the earlier adopters of the MD-UV380, its now worth updating your radio to this latest firmware which supposedly fixes something with the DTMF, channel write faults and contact database related functions, but nothing in 17.05 is a major upgrade.

After updating from FW 16.05 and 16.06, there is no easily visualized changes when moving to FW 17.05.  It is very important to use the right firmware or your radio may not function properly and you will then need to re-install the correct version. TYT website is here: 

August 2018 Customer Programming Software (CPS)  Version 1.07 and 1.08

CPS version 1.07 and 1.08 are prepackaged with the FW 17.05 on the TYT website and there seems one small change compared to using CPS 1.05.

When trying to import the user database and writing that to the UV380, the software does not seem to crash.

It is still advisable to save any changes you make to a code plug and put it somewhere safe as covered in the "60 Days with the MD-UV380" article posted earlier this month.

Updating MD-UV380 Firmware

If the TYT MD-UV380 is your first TYT DMR radio, you may be puzzled by some of the cryptic instructions and menus on how to update your radios firmware.

The utility called "FirmwareDownloadV3.04_EN"  is what needs to be installed on your computer. This same utility can also be used for all other TYT products so is worth keeping it handy.

Beyond being able to update the radio firmware, it also lets you add a custom "splash screen" to be displayed when the radio powers up.

MD-UV380 splash screen
The size of a replacement image on the TYT MD-UV380 needs to be
 a BMP file no larger than 128 by 160 pixels of 64 by 128 pixels at 8-bit, 256 color.

Once you have decided which is the correct firmware for your radio, navigate to where the update tool installed to.  On Windows 10, mine defaulted to:

 C:\Program Files (x86)\FirmwareDownloadV3.04\DMR Firmware DownLoad v3.04_En

Select the "Open File Upgrade button, navigate to the downloaded new firmware and
then press" Download file of upgrade"  AFTER you put the MD-UV380 into DFU mode
 and have the programming cable connected to the radio.

In order to put your radio into "DFU Mode" which is required to get the radio ready for new firmware, plug the USB cable into your computer and radio. Then, hold down both the PTT and button above it while turning the radio on.  The LED on the top of the radio will alternate flashing green/red to let you know the radio is ready for the update.

Now open the update tool and proceed to load the correct firmware version for your radio.  A progress indicator will let you know its status and when it is complete.

After the update is finished, turn the radio off, unplug the cable from the radio and then turn the radio back on.

Now to make sure it updated, go to "Menu" then "Utilities" followed by "Radio Info" and finally, "Versions" which will show you the current firmware and the last version of the CPS you used to program your radio.

uv380 firmware
TYT MD-UV380 showing a successful update
to FW  17.05 on the GPS enabled version of the radio

Downloading From TYT Website

Sometimes the TYT website can be slow, but not too slow. If you would like a slightly reorganized set of files related to this article, here is a link to download everything you need to upgrade to FW 17.05 along with CPS 1.07 and 1.08 hosted on the HVDN web-server.

Thursday, August 16, 2018

Digital Voice Capable Radio (DMR) Made In South Dakota?

The Federal Communications Commission (FCC) website has all sorts of interesting information.

You can find out where certain frequencies are licensed to be used, look for information on who should be using certain frequencies and also learn about what RF equipment is certified for use in the United States to name just a few.

Over the past few years, not every device that gets sold in the United States seems to be 100% certified under rules such as Part 22, 90, 95, 97 or many other FCC laws that determine things like "acceptable interference", "operation on amateur radio spectrum" and "equipment regulations for specific services".

If you have a device that transmits some form of RF energy in the United States, it should have an FCC ID.  But, as it turns out....not every FCC ID is real or are they?

K66 03770X30
The new Yaesu FT-818 FCC ID is real, but what makes
it real and how can you tell?

There are a number of manufacturers that sell equipment that list an FCC ID, but do not often follow the correct format or procedure that the FCC manages, so this article will cover a few examples of this.

Where is this on the FCC website?

The Office of Engineering & Technology is responsible for the certification of devices at the FCC among other tasks, many amateur radio and electronic hobbyists should be aware of prior to "experimenting" with different devices.

Here is the current link to where all sorts of searches can be run:

Many different searches can be run on the FCC OET website, but you need to
know a few things in order for it to work

Using the FCC OET Search Tool

Every manufacturer is assigned a 3 or 5 digit grantee code. This is the most important part in finding out information about a vendor. Some vendors have multiple grantee codes for different product types, but many only have one.

In the case of Yaesu of Japan, they have been assigned "K66" and doing a search for that will return the following results of 642 devices. You can further filter things by date range, frequency range and also how much information is shown in a table or what you can export as a file.

Yaesu had an FCC Grantee code of K66. There are 642 devices in the FCC database for this
grantee code, but the FCC site will only allow you to see 500 of them until you filter to a smaller date range.

Details For Each Device

If a piece of equipment is capable to operate in different parts of radio spectrum, the FCC must approve everything.

The Yaesu FT-818 radio for example lists four different areas of certification and there are many details that can be found by looking at the files attached to each.

While Yaesu is a company of Japanese origin, they do have a US office in Cypress, California and known as Yaesu USA  and this is widely accepted by most of the amateur radio community in the United States today.

Proper FCC ID process for the FT_818 Yaesu radio

You can usually find operating manuals for most amateur radio equipment, smartphones, Wi-Fi devices and so much more which is a handy thing to have.

You can also find some internal and external photos as well as a number of certification documents. This represents a milestone achievement for the United States government in offering a clear benefit beyond spectrum allocations to the amateur radio community.

The FCC OET database is also a great tool for finding out about near future release products since a manufacturer is supposed to have an FCC ID and all the related testing completed prior to selling an RF emitting device in the United States.

Some Strange Results...

Sometimes there is a small gap where a product is already for sale, but the FCC ID process has been delayed. If doing a search for an FCC ID or even just the grantee code and not coming up with much, what could that mean?  It could mean a lot and here are a few examples of this.


HVDN has reviewed the new dual band TYT MD-UV380 DMR handheld radio back in May 2018 when it was first released. As of August 16th, the FCC ID still is not listed.

Searching for the grantee code of "POD" does not show this. Much of this radio is based on the MD-2017 released a year prior under the FCC ID of "POD-DMR2" and everything you should find is easily accessible on the FCC OET website.

TYT MD-UV380 released in April 2018 

It is not clear if TYT needed to apply for a new FCC ID for the MD-UV380 or have they just been able to "sort of" use the MD-2017 one to cover the MD-UV380. 

Compared to Yaesu, the FT-818 is an updated version of the FT-817 released over 15 years ago. Both radios are identical, but because of a need to source updated components, some efficiency was gained in the FT-818 allowing 6W of power output instead of the 5W in the FT-817.

It is not clear if this is why the FT-818 has a new FCC ID of K6603770X30 and the older FT-817 has the FCC ID of K66FT817.

Could the RF parts of the MD-2017 and MD-UV380 be so similar to not require public listing in the FCC ID database?

So the question remains about why the TYT MD-UV380 still can not be found as a certified device on the FCC website even though it lists an FCC ID of POD-DMRUV very clearly as shown in the HVDN MD-UV380 teardown.

The TYT MD-2017 under the FCC ID of  POD-DMR2 was easily found when looking up the POD grantee code.  Other products were listed too, but not the MD-UV380

Ailunce HD1

Ailunce is a premium brand assigned to another dual band DMR radio that is manufactured by Retevis.

Retevis offers product that look identical to the TYT or legacy Tytera branded radios prior to being forced to re-brand and re-certify due to patent infringement situations between Hytera and Motorola Solutions.

For example, the earlier mono band VHF and UHF versions of the Tytera or TYT MD-380 also go under the brand of Retevis RT-3 and RT-82.

Looking for the grantee code of 2AAR8 lets you easily find more information about Retevis, who incidentally according to the FCC is really doing business under the name of HENAN ESHOW ELECTRONIC COMMERCE CO., LTD. out of China.

Today, TYT is doing business under the name of  TYT ELECTRONICS CO., LTD  of China but when they sold product under the name of Tytera, they were known as Shenzhen Tianjian Telecom Technology Co.,
The Ailunce HD1 created by Retevis has an FCC ID that is not found in the
 FCC database, but has been on the market for over a year

The FCC ID for the HD1 as printed on the radio is 2AAR8AILUNCEHD1 and was released for sale almost a year prior to the TYT MDUV380, but still does not appear in the FCC ID database and it is not clear why that is the case. There is no other radio similar in design cosmetically or electrically to explain this currently.

Anytone AT-D868UV

Anytone released a dual band DMR handheld radio for sale in the United States and the official business name of Anytone is Qixiang Electron Science& Technology Co., Ltd and lists different  addresses in China, just like Retevis and TYT do as where they are headquartered.

Anytone has the FCC grantee code of T4K. The Anytone AT_D868UV FCC ID of T4KD868UV is listed and it appears that Anytone has gone to great length in certifying this radio for different services covered under FCC Part 90 as well as Part 22.

This company even registered for separate  VHF and UHF only versions which is interesting and who they say it will and will not be marketed to which shows a focus of compliance not found with other Chinese brands.

The Anytone AT-D868UV, TYT MD-UV380 and Ailunce HD1 are the three current dual band DMR/FM radios that seem to be most in demand by the amateur radio community a the time of this article, but there is a new radio offered by BTECH called the 6x2 that has some even more background than many might be aware of.


Every DMR radio mentioned in this article clearly has Chinese origins just by looking at the addresses listed as part of the FCC ID listings. Even the engineers that certify the products are of Chinese origin, so it does show there has been mostly great care in trying to follow US FCC related regulations, but some interesting points to be discovered.

BTECH is sort of the new name for the Chinese company that made most people aware of amateur radio equipment that was low cost named Baofeng.  Baofeng started to release product in the US market as early as 2010 and got many people into the somewhat expensive amateur radio hobby.  Analog dual band radios before Baofeng came to market were mostly over a $200 USD price, but Baofeng was able to offer a fairly capable radio for under $60.

The inexpensive Baofeng UV-5R that has helped
 get more people interested in amateur radio since 2010

Recently, companies like Baofeng have been in the news for manufacturing products that are capable of transmitting on frequencies in use by licensed public safety  and GMRS or other unlicensed services such as PMR, FRS and MURS. Certain re-sellers have gotten in trouble for who they have sold these radios to because the Baofeng radios are not certified to be used on frequencies other than those used by amateur radio.

BTECH is based in Arlington, South Dakota now according to the FCC OET database.
  Here is where they are on Google Maps

It is an interesting discussion to have when talking about who is liable since a manufacturer can not enforce who its sales channel sells its product too, so this gives some companies a bad reputation.

Many well known amateur radio brands such as Kenwood, Icom, Yaesu and Alinco have always had the capability for out of band transmission, but required a modification to do so. Baofeng and other companies like it could have taken this precaution, but have not.

Radios reviewed in the 2017 entry level DMR article on HVDN
An updated article for release for 2018 will appear in September or October 2018

All of the DMR radios mentioned all are capable of out of amateur radio band transmission and require no modification, so what makes the BTECH 6x2 different? Its still possible to transmit where you are not supposed to, so that is not it.

For starters, its "identical" to the Anytone AT-D868UV. Most people already figured that out, but there are some "special" functions that help make it different like a store and forward voice recorder also known a a "simplex repeater" and also some more convenient scanning/priority options.

BTECH 6x2, designed in China and certified for the US market.

What many may not be aware of is that BTECH now technically is a company based in South Dakota, United States.  This was learned by looking at the FCC OET database.

The BTECH 6x2 hails from South Dakota, but with permission to rebrand it by Anytone.

Here is a letter found  by clicking for "details" for a change of ID request between BTECH, formerly sort of known as Baofeng Technologies and Qixiang Electron Science& Technology Co., Ltd. who is better known as Anytone.

Now What?

Its clear that there is a lot of confusion on who designed a radio, who really owns the brand and if it is legal to operate certain equipment on certain frequencies in the United States. The FCC website can help determine legality by doing your own research instead of believing what others may say or report on.

If there are any errors in this article, HVDN wants to know about them and hope you enjoyed this article. Please rate this article below so we know we are doing a good job or not.

Monday, August 13, 2018

60 Days with the TYT MD-UV380

On May 31st and June 5th of 2018, HVDN released a two part internal tear-down of the new TYT MD-380 dual band DMR radio.

The TYT MD-UV380 was released in May 2018 and will only get better with time. 

Since there were still many quirks and curiosities in the actual operation of the radio still be explored, starting a review from the inside out seemed a better way to go about determining if the "UV380" was a keeper or not and avoid getting frustrated by any potential lack of polish on the user interface of the radio.

If you missed those articles, here are the links to check them out:

Far too many new amateur radio products have been rushed to market over the past few years due to the growing complexity of them, but have later been fixed and transformed into much better user experiences.

Some of these of rushed products include the Icom IC-7100, Yaesu FT-991, TYT MD-2017, Icom IC-7300, Baofeng DR-5R and Ailunce HD1 to name just a few.

ham radio firmware upgrades

As of August 10th, much has been learned directly and from other early adopters of the TYT MD- UV380. Here is a more "operational" review of this latest mid tier digital voice radio.

Please note that this review is of the GPS enabled version only.

Firmware and Programming Software Review

The firmware shipped with the MD-UV380 was S15.021 and quickly upgraded to S16.06, but then downgraded to S16.05. The reason for the backwards downgrade by Steve K2GOG was because at the time the programming software seemed to work better with 16.05. 

As of the time of this article, there is a version firmware that has been shipped from TYT vendors for the non-GPS version, but this is not to be found on the TYT or any vendor website.

The Radioddity GD-77 has also started to see new firmware loaded from the factory, but not to be found on the manufacturer website. If this is a trend, it is worrisome for users looking to upgrade or downgrade radios.

The current most up to date "official" radio programming software or CPS as of the date of this article is 1.07. There has been a version 1.08 and 1.09 floating around some user groups, but seems to "sort of work" and it not being recognized as official.

For those with the MD-UV380 GPS version, its suggested to actually use the CPS and FW for the MD-UV390 which is slightly larger and offers water resistance capability.

MD-UV380 Suggestions

As of August 10th 2018, I would suggest using S16.05 as the firmware and CPS 1.05 as the programming software as they seem to have the least issues for the MD-UV380 with GPS.

MD-UV380 Improvements Since Official Release

#1) Probably the greatest improvement since the release of the radio is Tom N0GSG's popular contact manager software being able to support the TYT MD-UV380.  This freeware with suggested donation allows easier moving of programmed channels and contacts into a more usable order compared to when programming the TYT MD-UV380 with the manufacturer supplied programming software.

TYT MD-UV380 software contact manager
N0GSG's popular "Contact Manager" software
as of August 1st 2018 supports the TYT MD-UV380

#2) Another improvement since the TYT MD-UV380 was released is better handling of loading in the user contact database to the radio. This is helpful in order to show call-sign, name and location information for each DMR user instead of either trying to memorize the 7 digit ID's for everyone or loading them one at a time.

The website is the best place to get the current version of the user database for the TYT MD-UV380.  As of the date of this article, the user database has 105,212 registered users and all of them fit within the UV380's memory. It is believed however that once the user database exceed 120,000 contacts, the radio will ignore all users over the maximum number the radio can hold.  Users not stored in the database will show up as "unknown". 

After you create a user database file from the, such as this sample created for the date of this article, there are a few things to be mindful of:

#3) The TYT MD-UV380 uses the same format for contacts as the TYT MD-2017.  Code plugs can also be directly imported which is nice.  If you have an older mono band MD-380, you can first open that code plug in the MD-2017 CPS of choice, save it and then load it into the MD-UV380.

#4) Before loading contacts, save your code plug often. The CPS may crash sometimes and not save recent changes.

#5) When loading contacts into the TYT MD-UV380 via the CPS, after using the "import button" you need to wait for the "Import Succ" message to appear before then writing the database to your radio

Make sure after importing the database you get
 the "Import Succ!" message before writing to the radio

#7) On your MD-UV380, you will need to enable CSV database for the contacts to appear. You  do not need to have Microsoft Excel to do this contrary to what some people say.  If you do want to edit the contact file, you can use freely available OpenOffice

#8) Almost everything can be programmed without a computer, but requires a certain order to do it. First you need to create a channel and create a zone.  You then need to assign the channel to a zone in order to use it.

#9)  Its possible to enable a VFO mode in the CPS, but its not 100% clear how to access this mode if you reassign any of the buttons on your radio.

#10) If you program a side button for "monitor" you can see frequency and channel info which is nice

There is a lot more to say about this radio and the only thing it seems to miss out on is better "keypad" dialing of talk groups like what MDtoolz does for the MD-380 series or even the Anytone D868 and BTECH 6X2.

Share your observations and tips here if you want or in your favorite Facebook group.

Sunday, July 29, 2018

Knowing When To Hold'em and When to Fold'em: Timing The Sale of Ham Radio Treasures

Ham radio as a hobby can get expensive and is also easy to accumulate too much stuff over the years. Since this hobby is part driven by technology, certain items get outmoded or outdated.

Knowing when to buy and sell something is a part of this hobby that needs a little open discussion.

Kenny Rodgers is known for his song "The Gambler", but its not clear if he gambles when it comes to ham radio related purchases or not.

Finding ways to keep ham radio manageable and affordable is something I have always tried to do while at the same time trying to have some of the latest and greatest toys to get on the air with and talk with other radio amateurs.

This is an example of modern amateur radio with many technologies ready to experiment with

Today, technology is moving much quicker than it was just thirty years ago and I wanted to quantify a few things based on some recent on and off the air discussions with other amateur radio operators.

When it comes time to decide what projects to fund and decide what is worth hanging on to or selling  off,  its become apparent that more people or loved ones do not want to get caught with a basement full of ham radio treasures that not many will see a value in.

The beauty is in the eye of the beholder with this messy basement "ham shack"

A Ranking Of Sorts

What I set out to do was find what were some of the most influential, affordable and most widely used amateur radio equipment put into the market between 2018 and 1988, which is a 30 year window to cover and do a little bit of a ranking for fun.

I came up with two general sets of parameters or axis's of  sorts called innovation and implementation.

Each axis has a small subset of criteria to better sort things further.

Implementation Axis

Implementation has to do with a vendors success in getting product into the hands of amateur radio operators.  Three sub-criteria were used to calculate overall implementation scores for specific models of radios that have been widely used. 

Affordability, accessories, accessibility and launch versus current market pricing value are the four areas looked at.

Affordability is a relative term.  Based on the price at launch of the product and what its current market value is today in 2018 were used to determine this criteria. An example of one would be Kenwood TH-F6a  tri-band handheld radio launched in 2001 for around $325.00 and is still in production today. 

Used market pricing varies because of how long this radio has been on the market, but generally sells for between $150-$225 used.

A scale of 1-10 in curved graduations of around $100 increments were used.  A score of something costing new between $389.99 and $499.99 was given a 5. A score of 10 was assigned for anything that was newly priced at under $100 dollars.

A score of 1 was assigned for anything that was newly priced over $1,000 dollars.

Kenwood TH-F6a  SSB with 144, 220, 440 for sale
The Kenwood TH-F6a was unique when it launched in 2001 for including the ability to monitor the HF bands in SSB mode as well as operate on the 3 different VHF and UHF bands in use across the United States. Almost 18 years later, there are only two other radios that would compete with it.

Accessories are something that can contribute over time to the enjoyment of certain equipment and may be purchased right away or over time. Some accessories are offered by the manufacturer who released the radio in question. Others are aftermarket items or easily built by amateur radio operators themselves.

The robustness of the accessory ecosystem was simply graded between 1 and 10, with 10 being the most accessory options imaginable and 1 being the very least. Of the 30 official radios used in this ranking, the average for accessories turned out to be 6.5 which shows the market saw a lot of additional opportunity beyond just buying the radio itself.

Accessibility is a combination of a few factors.  At some point in time was it possible to go in to a physical store and purchase the radio? If you asked someone "Do you know anyone who has this radio I can talk to before purchasing it?" and "I saw XYZ at a recent hamfest walking around with it and I think I may want to get one" is some of the thinking that went into this accessibility ranking.

In the last thirty years, we have gone from only local store, mail order purchase and long decision times to almost instant internet based research, purchase and next day delivery.

In order to not take into account inflation,  it was simple to look at the pricing for when a radio was released and what it is currently selling for today on the used market. Even for equipment released within the last 24-48 months are easy to see what is holding market value based on when something newer is available.

In years past, certain radios held value longer than others or dropped value quickly.  Equating a percentage for example of when then the popular Radioshack HTX-242 which launched in 1998 for around $299.99 is worth about $50.00 on a good day 20 years later or less then 14% of its original value.

Radioshack HTX-242 for sale
The Radioshack HTX-242 was the first 2m mobile radio for many ham's from 1998 until 2003 and saw high adoption becuase it was easy to purchase in person from a local store instead of waiting on the pre internet ordering options of the day. 

Innovation Axis

What prompts most amateurs to buy something over another is what can it do that no other product can at a price that seems reasonable.

Also, what else can it be made to done that it was not thought of by the original designers had intended is another. 

Three total sub-criteria were used in the innovation axis and they are direct competition, features and modifications

Direct competition comes in waves for most of the larger radio vendors such as Icom, Yaesu, Kenwood and others. Every so often these or other more narrow vendors come up with something so unique and fascinating, there is often no direct competition.

A great example when it launched and for years right after is the Yaesu FT-817 multi-band multi-mode portable radio that opened up new ways of operating or attracting new hams into the hobby.  It was clear early on Yaesu had a hit on its hands since its launch and only recently saw a minor refresh due to changing part suppliers, but even the new FT-818 replacement is honestly not that different than the original.

A scaled of 1 to 10 with 10 being the least amount of direct competition at launch was used to rank each of the 30 radios.

FT-817 for sale
The Yaesu FT-817 proved that ham radio was not a basement hobby any longer. This radio allowed you to take the entire "ham shack" into the woods and beyond for all sorts of adventures for a modest price

Features are in the eye of the beholder sometimes. Some are fact and  based on specifications or instruction manuals, others are more mental for certain people.

The idea that even like designed radios could vary much in features is hard to grasp, especially when some amateur radio operators will go to great length to dispute which radio is better than another even though they are very, very similar.

A scale of 1 to 10 was used to rank features relative to competition available at the time of launch.

Lastly, modifications was used to define innovation. This is not just about clipping a certain green wire in some radios, but really looking at how quickly users figured out ways to make something better and widely documented the results.

Everything from changing certain capacitors to make certain radio sound better on different modes, to re-writing the operating software running the most widely adopted modern radios was taken into account in the ten possible points available for the most modification friendly radio out there. 

Other Criteria

To increase the objectivity, no one vendor could have any more than five radios in this list of 30, save for a honorable mention of a very unique radio that paved the way for many innovations still not seen today.  Also, only ready built and major commercial vendors were included.  

The idea for what would make it on to the final list of 30 amateur radio items over the last 30 years also was focused on mass adoption versus niche purchases or devices. 

Anything that proved to be a huge hit for a particular vendor was included and balanced against rigorous research from the opinions of many amateur radio operators globally about some of the most popular equipment they own or seem to always talk to someone on the other end about what they like or are using.

The List You Have Been Waiting For

It was really tough to develop this list of equipment, but I can pretty much guarantee that if you have been a ham for at-least most of the past 30 years, you will recognize the majority of this list. Some items were chosen to keep things manageable and not dominated by one vendor or another.

The top 5 items with score go to:
  • Baofeng UV-5R (875.8489706)
  • Inexpensive SDR USB Dongles (827.2830524)
  • TYT MD-380 (769.8098983)
  • Anytone D868A (732.5622234)
  • Alinco DJ-596 (645.3345454)
The bottom 5 scored items with score go to:
  • Kenwood TS-2000 (174.0128162)
  • Icom IC-746 (167.6209362)
  • Yaesu FT-991 (151.9583962)
  • Kenwood TM-742 (144.8730979)
  • Yaesu FT-100 (138.1904794
Honorable mention, just to see how it would have scored had it been a bigger hit goes to the obscure Icom IC-900 mobile radio system.

Here is how it fared against the 30 most innovative, influential, affordable and widely adopted amateur radio over the past 30 years.

Icom IC-900

What made this radio unique in 1987 and even today, 31 years after its launch was its complexity and flexibility.

This was a modular radio system that bolted together to offer the user all sorts of band or mode options and then output to a control head using fiber optic cable up to 65 foot in length.  

Icom IC-900 for sale value
The Icom IC-900 is obscure but pretty cool even 31 years later

Its hard to find accurate pricing on this radio and how many Icom actually sold, but its estimated that the options to make a 2m, 70cm only version would have cost at-least $900 when this was on the market.

Today, these still demand a good price because of its rarity and innovation and is why it received the honorable mention and a scoring of:
  • 2 for Affordability
  • 2 for Accessories
  • 10 for Direct Competition
  • 8 for Features
  • 2 for Modifications
The estimate for pricing was hard to place, but looks to be about 44% of its original sale value today, but this could be on the very best or very worst day.

Does this obscure radio look anything like what we see today?  If you are thinking of the current Icom IC-7100, then yes.....maybe it does

Icom IC-7100 for sale
The Icom IC-7100 is a modern marvel, but is it for you?

The total innovation score worked out to 20 and 6.4 for implementation. A final score calculated to 56.65691462, which was far, far below what the Yaesu FT-100 got in the top 30 ranking found here for download.

Wishful Thinking

It would be a huge undertaking, but it would be interesting to develop a larger database based on details found on websites like, plus others and then refresh the list annually in order to compare over time how the market changes for amateur radio equipment that is in demand. 

Register for updates to the HVDN Notebook to get the full scored list of equipment

The summary of equipment in approximate order by release date is below:

Subscribe To Future HVDN Notebook Updates Here