Teardown & Comparison: TYT MD-UV380 Part 1

The dual band TYT MD-UV380 has just been released and promises much of the same functionality of the TYT MD-2017 and Retevis RT-82, but in the same form factor as the ever popular mono-band MD-380 and MD-390 series of radios.

This review goes under the hood of this latest $149.99 priced DMR & analog FM dual band handheld radio.

RF deck top view of the MD-UV380

Basic Overview

The MD-380 has been well reviewed elsewhere plus in past articles here on HVDN like the 2017 DMR entry level radio review.

The new MD-UV380 and MD-UV390 look identical to the mono-band versions and also include options with or without GPS.

Here are some side shots of the MD-UV380 (GPS) box which is somewhat informative on specifications.

Out Of The Box Differences

The firmware version out of the box for this sample was S15.021.  The latest version as of the date of this article appears to be S16.06 based on the TYT website download from May 23rd 2018.

While scrolling through the features in the CPS 1.03 and then updated into the radio to unlock certain menus, the major feature add on with the MD-UV380 is the ability to have up to 3 radio ID's and to change the mic gain.

Everything else is pretty much the same as the MD-380 stock firmware flow, not including the obvious addition of VHF and UHF coverage, like the MD-2017.

One feature introduced in the MD-2017 was built in "promiscuous" mode that allows monitoring of all DMR traffic on a specific time slot and correct color code. This has also made its way into the MD-UV380.

Also, like the MD-2017, the MD-UV380 can either allow audio to be recorded in DMR mode or provide the user with more contact storage space for the entire DMR ID database. Different firmware exists for either option for the MD-UV380 or MD-UV390.

From an outside hardware perspective, the MD-UV380 uses all the same accessories as the MD-380.  Same goes for the MD-390, which is just slightly larger than the MD-380. This is nice in order to recycle things like chargers, batteries and programming cords between the old and new radios.  The GD-77 by Radioddity also uses the same charger as the MD-380, so for users looking for a new dual band radio may want to consider the MD-UV380 over other similar radios.

The included stock dual band antenna seems to be of slightly higher quality compared to the antennas included with the mono-band MD-380/390 radios. The base of the MD-UV380 has an extended ferule to provide a little more waterproofing on the antenna connector on the radio.

Navigating the MD-UV380

Compared to the MD-2017 with its roller ball navigation, the MD-UV380 uses the arrow buttons below the display to flip between the upper and lower band assignments. This makes the UV-MD380 more like the Radioddity GD-77 or Anytone D868A from a navigation factor which is slightly less cumbersome than the MD-2017 roller-ball and will likely hold up better over time and prevent accidental band swaps or channel changes.

Channel selection in either the upper or lower band on the MD-UV380 is done through the top mount multi-selector knob. Compared to the MD380, there is no more limitation to 16 channels per zone which was sort of hard coded against the 16 position channel selector knob.  On the MD-UV380, as many as 64 channels per zone and possibly more is possible.

There will be more to talk about when it comes to the firmware updates, upgrades, channel management and overall user features, but that is not the main goal of this tear-down and comparison.

On the outside of the MD-UV380 from a distance, it would be hard to tell the difference between the MD-380, MD-380G, MD-390 and MD-390G. They all look the same and the only differences is the multi-selector knob, the label under the battery showing the model name and button coloration differences.

Inside the MD-UV380 and compared to the MD-380G

This is where things get interesting because the outside looks the same, but the inside does not.  Here are side by side comparisons of the MD-380G and the MD-UV380 (GPS). The outer-casing on the MD-UV380 seems to be styled like the earlier TYT versions whereas later ones had a more rounded speaker grill and colored buttons.

MD-UV380 on the left and MD-380G on the right

Things get interesting when looking at the two parts of the radio side by side after opening both up.

The MD-380G and MD-UV380 share the same exact board numbering for the user interface side of the radio as noted by KEY-V2.0-160329 text.   In the upper left corner near the speaker you can see the GPS antenna.

MD-UV380 on the left. MD-380G on the right.
Note the colored orange and blue buttons on the right side of the MD-380G

Swapping the RF deck from either radio with the UI board from the other confirms there is only one tiny difference.   The flat cable connector on both is slightly different which may just be a sourcing reason.  The connector on the MD-380 was a "piano hinge" type and the MD-UV380 was "compression lock" type. The flat ribbon cable fits the same way. Its possible over time that the "compression lock" version may be more reliable and limit the potential "white screen" issues some users have experienced when the connector and cable are not mated tightly at the factory.

Both radios upon re-assembly with the UI board and RF deck from both models confirmed identical operation and functionality. 

Should someone want the slightly more rounded housing and colored buttons from a MD-380G, but with the functions of the MD-UV380, this may be good to know.

The UI is the same but not the RF deck

As you would expect, the design of a dual-band radio would be just a little different than a mono-band version. Here is a side by side of both radios from the inside.

MD-UV380 at left and MD-380G at right

The major differences here get sort of fun. The same STM32F405 is used across both radios, but gone is the HR C5000 base band chip on the front side as in the MD-380.

In the MD-380G, the ST Microelectronics STM32F405VG is used which sports an ARM Cortex M4 core, up to 168MHz clock speed and 1024 KB of on board RAM. A more detailed spec sheet can be found on the STM website here.

The new MD-UV380 has the same STM32F405VG, but with slightly different date codes. It is unknown without further dissection if there are any small changes in the MCU since there is likely 2-3 time difference between the manufacture of both radios.

The "527" version was found in the MD-380 and the "664" version was found in the MD-UV380

Both radios also have the same Winbond 128K memory (W25Q128FV), but you may notice an empty pad for possibly an additional memory expansion on the MD-UV380.  This may be helpful as the user database for DMR ID's soon surpasses 100,000 which is the current limitation of many radios. As more DMR uses experiment with GPS, SMS and other mode translations such as those just introduced in Pi-Star, having additional memory will be a useful thing to have.

Note the empty pads for additional memory such as the 128k Winbond chip to left of  STM32F4055VG

For those that remember, the VHF versions of the MD-380 had less memory compared to the UHF versions which limited further alternative firmware development made popular by Travis Goodspeed, Ty Weaver, Warren Merkel and many others.

Perhaps lessons have been learned with the MD-UV380 to allow for future memory upgrades without complete redesign.  Its clear that TYT used the same UI board to simplify construction and offer a lower priced radio.

It seems all they really needed to do was just redesign the RF deck on the MD-UV380 after learning from the success and failures of the MD-2017 user interface and overly sized casing.

RF Front End

The RF front end is a combination of filtering for radio transmit and receive functions. On the MD-UV380 we can see some of that by looking at the SMD capacitors, resistors and inductors between the antenna connector and the copper pad which is a heat spreader for the RFPA on the underside of the RF deck board.

The MD-UV380 is a 136-174 MHz and 400-480 MHz radio, so its filtering would be more complex as expected compared to the UHF only version of the MD-380G.

MD-UV380 on left. MD-380G on right. It appears here that that the MD-380G is more complex on the rear of the RF unit compared to the MD-UV380. There has to be additional components on the underside of the RF deck board

Is That It? 

Clearly the top side of the  MD-UV380 seems more simple from a base-band perspective compared to that of the MD-380, but that is likely not the case.  All we have learned so far without further disassembly is the following:

• Both radios appear to use the same STM MCU
• Both radios have the same Winbond flash memory
• The MD-UV380 seems to have the ability to increase on board memory due to empty pads.
• The MD-UV380 may be using something else for base-band RF compared to the MD-380
• The UI boards are common across both radios
• The older style  and slightly larger housing from earlier MD-380 radios is used for the MD-UV380

Next Steps

The intent here was a basic under the hood look at the MD-UV380. Future coverage will include the underside of the RF deck and more about how the radio functions on the air plus other "deeper under the hood" analysis. 

One quick comment: Its possible to save a VHF or UHF frequency for transmit and the other band for receive.  Its also possible to save frequencies in as small as 2.5KHz steps. This may be of interest for those interested in satellite communications.

Stay tuned for more MD-UV380 coverage here on HVDN.  

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http://notebook.hvdn.org/search/label/DMR 

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That was quick. DMR to NXDN

It only took less than 48 hours for the fantastic Pi-Star and MMDVM development teams to release the ability to translate DMR into NXDN.

It's time to update your ZUMspot, JumboSpot or whatever other "spot" device to give this latest feature a try.

Color Change on Pi-Star

Has the red, white and gray color scheme on Pi-Star sort of worn on you?  

If it has, one of the latest feature additions to Pi-Star is the ability to change the coloring to your liking thanks to the "CSS Tool" that came part of 3.4.14.

On something a bit more technical, there is also the ability to do cross mode translation from DMR to Yaesu Fusion. This means, you can now take your DMR radio and talk across to Yaesu Fusion users. This was only possible on the Shark RF OpenSpot device previously.

In version 3.4.13, we saw the ability to go from Yaesu Fusion into DMR, NXDN and P25.  In 3.4.14, it is now possible to go from DMR to YSF. Will NXDN or P25 be far behind?   And, no one cares about D-Star anymore anyway.....  Just saying...  :)

Pretty Colors

You can navigate to this "change the colors" tool by going to "Configure", "Expert" and then under tools "CSS Tool"

Alternatively, you can also navigate to your Pi-Star dashboard with "/admin/expert/edit_dashboard/php" after your local IP address

To change from the standard red "ffffff" background to the teal "6497b1" all you have to do is change as per image.  To figure out how to edit hex into colors, here is a handy website:  http://www.color-hex.com/ 

Infusing Fusion with DMR

The list of cross mode translation keeps growing and the DMR to Fusion is the latest. Its now possible to go Fusion to DMR and DMR to Fusion which is real nice.

All you have to do is set your DMR radio to talk group 7 and configure the below new setting to go where you want it in order to access that part of the Fusion network.

YSF Startup Host will offer you may options.  APRS Host is if you plan to use location or message sharing functions.

Free Aircraft Tracking: Memorial Day Break

In honor of Memorial Day in the United States, our Field Strength Meter Monday series is taking a one week vacation. 

HVDN will also be offering FREE access to our regional ADS-B air tracker to help see what may be flying in and out of the area this week  and next related to the upcoming air show on Long Island.

Here is a summary of "Field Strength Meter Monday" posts already and more details about the Long Island Air Show which has a lot of wireless communications involved too!

• May 21st: Field Strength Meter Monday: Say Hello To A Smart F.S Meter Part 1
• May 14th: Field Strength Meter Monday: A New Modern Low Cost F.S Meter
• May 7th: Field Strength Meter Monday: 3 Real World Applications For A F.S Meter 
• June 30th: Field Strength Meter Monday: General Overview

Outside the Hudson Valley Memorial Day events of interest to Amateur Radio people...

• Long Island:  Jones Beach Air Show  
• Listening to the Air Show via w2lie.net 
• Bergen Amateur Radio Hamfest

Gain access to HVDN ADS-B Tracker

• Visit atc.hvdn.org

• Enter the user name "mmd2018" and "mmd2018" as the password.

• Be sure to look at the instructional video on key features such as running reports to get the most of it.

• Joining HVDN will provide extended coverage range via a different receiver and year long access

Next week will see the return of Field Strength Meter Monday and some details about connecting the RF sensor to a compute device such as an Arduino or ESP8266.

Upcoming HVDN MMDVM Hot Spot Project

Here is a preview of an upcoming HVDN project involving a full duplex multi mode digital hot spot for use in the car or in person demonstration.

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May 2018 Global Digital Repeater Round Up

HVDN thinks its a good time for a global digital repeater growth snapshot before the next official update in October.

With the Dayton Hamvention of 2018 wrapped up this past weekend and new digital radios announced such as the dual band DMR focused TYT MD-UV380, MD-UV390 and Alinco DJ-MD5T hand-held radios. Yaesu Fusion also now has additional new equipment available thanks to the new FT-70 handheld and FT-7250 mobile.

These new radios will likely create demand for more repeaters as the number of affordable equipment options increase.

Here is the raw data from the chart above

Observations

• HVDN is not aware how repeaterbook.com keeps track of its data, but the NXDN repeater count shrunk by 2 where all other digital modes grew.  

• DMR by far had the most growth in just the past few months as well as the past few years. 

• DMR also now according to repeaterbook.com data is the highest number of digital repeaters

• D-Star is still a very widely deployed digital mode, but its growth is very flat compared to all other modes

• Yaesu Fusion may see some further growth thanks to recently released new radios and because MMDVM now supports cross mode translation which may potentially increase repeaters for those looking to experiment on NXDN and P25.

• Lower priced new dual band radios for DMR and Fusion are impacting demand for more repeater deployments the past 2 years.

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Field Strength Meter Monday: Say Hello To A Smart F.S Meter Part 1

 As part of the continuing "Field Strength Meter Monday" series, here is part of the schematic of a finished product to be released later this summer.

Detecting RF

Use of 1N34 germanium diodes have been the standby detector for a long time, but does not offer linear detection across a wider frequency range or sensitivity.   PIN diodes with a voltage bias increase sensitivity, but still do not have regulated output across a wide frequency range. This is why a new and low cost modern "smart" field strength meter is needed.

The HVDN designed Smart F.S Meter has the Analog Devices LT5507 as its RF detector.  The range is 100 kHz to 1 GHz, so this will find a lot of use for the amateur radio community.  Its also possible to use the LT5534 as a direct replacement to offer 50 mHz to 3 GHz range if desired for those interested in things like detecting 2.4 GHz Wi-Fi, bluetooth and more.

The LT5507 is small, in case you did not know. 

Moving to the LT5507 provides additional benefit as well compared to other older detector solutions. When RF signals are received by the LT5507 (or LT5534) the output signal is a calibrated voltage from -0.3 to +6.5 volts which  is easy to translate into RSSI values. This is important since it can easily be read by most analog to digital converters that operate up to about 5V, such as the embedded capability of an ESP8266 or Arduino.

Here are the datasheets for the LT5507 and LT5534 power detectors.

Basic schematic for LT5507 based RF power detector.

This uniform voltage compared to frequency received is what makes this a building block of  a smart field strength meter.

However, the LT5507 and LT5534 are not very sensitive for this purpose, so adding an operational amplifier (OpAmp) is needed.  The common LM324 is used for this purpose as illustrated in below schematic.

OpAmp expanded LT5507 RF FS Meter

In the "OpAmp expanded LT5507 RS FS meter" schematic, the "signal output" can be fed to a simple analog 150 mA meter, A/D converter as part of a ESP8266 or even a LM319 bargraph add on circuit for more visual readouts.

The 47K potentiometer can either be a regular analog one or a digital potentiometer which can then be manipulated by interfacing it to GPIO on an Arduino or ESP8266.    The function that the 47K potentiometer controls is sensitivity of the OpAmp up to 2x or to even reduce sensitivity by 1x.

Adding the "Smart" to the FS Meter

Now that there is a sensitive, broad banded RF detector that can output a signal that is easy to interface to, now we can start to look at integrating this with the "smart" aspects of the project.

Stay tuned.....

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A National DMR Location Services Proposal

On the way back today from the Southern Berkshire Amateur Radio Club’s hamfest at the Goshen Fairgrounds of Connecticut proved a good opportunity to try out mobile location enablement via DMR.

Here is what was involved to make this work:

• TYT MD-380G radio
• JumboSpot Hotspot device
• Mobile hotspot for internet via smartphone
• Correctly programmed radio and Brandmeister account setup.

Some Lessons Learned

Compared to using APRS, which uses 144.39 MHz as a common national US frequency and a network of stations to ingest users packet transmissions directly or via digipeaters and igateways that can route data from "over the air" and onto the internet. Using DMR and “APRS like” functionality is different in how that same function is accomplished since it does not use AX.25 1200 baud packet..

The only way to get user reported location or messages to the aprs.fi website and back to other radios  is via your own DMR hotspot or a local repeater that is set up to allow private data calls to be passed through to the internet.

Smart Beaconing & Power Savings

APRS and much of the equipment available today supports a feature called “smart beaconing” which allows a user’s radio to transmit location data more often while traveling at higher speed compared to sitting stationary. The number of "beacon transmissions" are reduced thanks to smart beaconing to create less congestion on the dedicated national APRS frequency. More about smart beaconing can be found here and its other benefits.

The current implementation of location services on GPS enabled DMR radios such as the TYT MD-380G do not support smart beaconing, but can be user programmed to always beacon at preset intervals.  Smart beaconing provides the major benefit of better battery life and better route accuracy for APRS. 

Wish List Item #1: Location enabled DMR needs this same capability, especially for portable/handheld radios.

GPS location is only sent at a present interval or during PTT on a DMR radio, so there is no "smart" capability at present time.  Accurate travel routes can thus only be created based on how frequent the user transmits which explains the rather strange route shown on aprs.fi for this experiment. Not having smart beaconing makes DMR location enablement to be less accurate for route tracking and efficient spectrum management.

Routing & Prediction

The second lesson learned is that the APRS.fi website does not fill in better predicted routes if DMR location enabled transmissions are missed. In the case of the route 199 in New York, there is horrible mobile phone connectivity and my mobile phone did not have internet access the whole time, which prevented any GPS transmissions sent from the MD-380 to the JumboSpot from being reported.  Since there are no repeaters that cover this particular area or offer private data calls, the only way to use location enabled DMR is via a mobile hotspot. 

Wish List Item #2:  More capable repeaters are needed to fully realize DMR benefits.

Even when entering back into better mobile coverage areas on parts of routes 199 and 308, it was not safe and appropriate to continue pressing the PTT to send location packets to better report accurate “breadcrumbs” on the route since it would congest the frequency I was using with my hotspot.

Even during a discussion with another DMR user via TG 310, my  DMR radio only transmits the location data at the start of transmission. Having 30-45 seconds of my own transmit speech and then listening to a reply for as long a period spreads out the rate of GPS transmissions, which inhibits quicker location reporting via TG 310999.

National Proposal on using DMR and GPS

Some ideas to aid in adoption of using GPS via DMR  includes:

• Add functions at the radio level that support smart beaconing rather than just setting a high rate of transmission or just via PTT. 

• Have the radio acknowledge when its transmissions are not confirmed as being sent to the internet and to “buffer” them for later transmission to fill in gaps on possible routing.  This involves saving GPS locations with speed of travel and altitude which is available on the radio. This solves the gap issue and is not far different how many automotive GPS's work when loss of sky coverage happens. 

• Create a network of receive only gateways on VHF or UHF to listen for data packets on common frequencies for the purpose of location messaging that will only pass traffic on a certain time slot (TS2) and destination talk group (TG 262993). 

• Adding on transmit capability for a repeater that will broadcast private data calls to users that will not impact voice users at the same time.

• Challenge repeater owners to add an additional equipment to support this function and make use of great siting available at repeater sites. Many repeater sites already host APRS digipeaters and have internet access so this should be easy to add and expand value offered by DMR.

• Decide on two national frequencies for GPS messaging and reporting use for VHF and UHF.

Why do this with DMR rather than just use APRS?

APRS does many things well and is fairly simple which makes it appealing, but its age is starting to  show.

A shortcoming of APRS is the inability to easily deliver an actual street address level of resolution to a radio. All APRS radios can only show coordinates, bearing and distance to another user which is limiting at times.

Location enabled DMR provides the ability to match coordinates to a physical street address and see that on the screen of the radio.  This works simply by addressing a private message to TG 262993 by sending "gps" as a message.  The reply message takes your radio GPS coordinates, matches it against mapping API's via Google Maps or Open Street Mapping project where it finds the street address and then sends that back to your radio.

Other commands summarized in a previous article also allows you to see distance, bearing and street address closest to another location enabled DMR user.

Location enabled DMR also lets the user request weather conditions the same way by messaging to "wx gps". The resulting reply matches up the GPS enabled DMR radio with closest weather conditions found on the internet. Temperature, humidity and barometric pressure is than easily viewed on relatively inexpensive DMR radios. 

If using an APRS radio, the user needs to spend much more money to see this level of detail or sacrifice some level of portability if not using some of the advanced APRS handhelds currently available. 

Weather and location are just two easy examples of how to use location data as a source for value added information.  Sending email, local frequency information for voice communication and other data are easily routed or sent from a DMR radio.

These are some modern ways in which ham radio can remain relevant in a world of smart phone dominated but mobile network dependent messaging.

Wish List Item #3: Adding functions like this are what ham radio is all about, so perhaps more DMR repeater owners will start considering adding a simple weather station, offline mapping database and secondary receivers to support some of this functionality. 

Here is some further related reading on HVDN if this sounds of interest:

• Location based weather on your DMR radio
• Easy DMR GPS with an MD-380G
• DMR for local communication

Field Strength Meter Monday: A New Modern Low Cost F.S Meter

Most relative field strength meters employ an analog meter. Some newer models use LED bar graphs or LED numerical displays.

Both types of indicators offer different benefits and is why a modernized relative field strength meter is needed to bring all the benefits of these display types together. 

Additionally, having the ability to "listen" to how a signal has changed would be nice to have.  The human ear can detect much smaller changes compared to those that are visual.  So, how about we make our own modern relative field strength meter?

Key design considerations include:

• Offer somewhat linear sensitivity across the entire design frequency range.
• Provide amplification and attenuation for different use cases
• Allow the user visual and audible customization indicators 
• Enable remote monitoring capability
• Balance cost and benefit to potential users

Evolution: Software Defined Relative Field Strength Meter

As covered in previous "Field Strength Meter Monday" articles, the components are pretty simple, but if we add more of a programming element thanks to a raspberry pi or arduino, we can do some interesting things by loading custom code and taking advantage of the different GPIO connections offered by these embedded computing devices.

Major Design Challenge

It would be nice to include the ability to remotely monitor RF signal strength since the human body can influence reception when standing in the RF near field.  Connecting a field strength meter to send its readings over Wi-Fi to a mobile phone could be an interesting feature to have.

Building This Thing 

It will be better to share a final product with HVDN readers to as to not confuse based on some half built, semi-functioning product or one that just works "theoretically".

When Can I See It?

Because HVDN wants to build a community with major benefits available to them first, the official schematic, parts list, code and other construction information will only be available to HVDN members for an embargo time period from the public.


Please join HVDN (Free) to learn more about this great project

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Location Based Weather on your DMR Radio

If you have a GPS enabled DMR radio, have you used that feature for anything?

How about getting real time weather conditions based on your location?

Over on the Hamdigitaal.nl website, there are some decent capability and functions discussed on what you can do relating to weather and location with your GPS enabled DMR radio.  Here is a portion of what you can do.  HVDN will share more detail on how to actually set your radio and hotspot to actually work.

The Brandmeister network has some functions to request information via SMS messages. To access these functions specific keywords are to be sent to DMR ID 262993. Then the system responds as well via SMS on these requests. Below you’ll find an overview of these commands with some explanation. The commands are not case sensitive.

Command Explanation
help Shows an overview of the available functions
echo Sends immediately a response to test the SMS function
wx Weather at the repeater site
wx help Overview of all available weather commands
wx Town Weather in the city ‘Town’
wx zip Town Weather in the area ‘zip’ in the city ‘Town’
wx zip, cc Weather in the area ‘zip’ in country ‘cc’
wx Town, cc Weather in the city ‘Town’ in country ‘cc’
wx zip Town, cc Weather in area ‘zip’ in city ‘Town’ in country ‘cc’
wx gps Weather at the actual position of the DMR user according to the radio’s GPS
metar xxxx METAR message at the airport identified by ICAO code ‘xxxx’
gps help Overview of all GPS commands
gps Shows actual GPS position including the name of the location (street, city) of the DMR radio. Also direction and distance in relation to the actual repeater are provided
gps set Stores the actual position as ‘Home’ location
gps home Shows distance and direction of the actual position in relation to the previously stored ‘Home’ position
gps callsign Shows distance and direction in relation to DMR user identified by ‘callsign’

Getting Things to Work

Would it be easy to share a code plug to show how this works? YES!

Will that help 100% understand the minutia of it? NO!

Here are some steps you will need to focus on and decide to make a code plug from scratch or add this to your existing code plug.

Advance Warning(s)

Regarding Radios:  I have only tried this on the TYT MD-380G (VHF and UHF versions) as well as the TYT MD-2017.  Other radios like the GPS enabled versions of the Anytone 868,  Retevis RT-82, Auilence HD1 and others may need to be tweaked slightly.   The new MD-UV380 dual band HT has not yet arrived at HVDN, but this will be one of the first things we will dig into to make sure its compatible with other radios.  Many GPS enabled DMR radios from different brands do not seem to work together which is annoying!

Regarding Hotspots:  This all works fine with the JumboSpot, OpenSpot and the latest full duplex hotspot devices. Derivatives that run Pi-Star should have no issue.

Regarding Repeater Use:  Please check with your local repeater owner if they permit private data calls on either time slot of a repeater. Many repeater trustees or operators wish to NOT allow private or data calls. Beyond checking with a repeater owner, there should be no reason for this to not work though. I have used a Micro Node TEENSY 3.6 based home made repeater and Pi-Star running on the host device and it worked fine.

Setting Up Your Radio

First thing you will want to do is experiment with adding GPS to your code plug and ensure you can get a signal lock. This will make your life much easier before progressing. Have a look HERE for more detail about getting the GPS "sort of" working.

Next, you will want to ADD A PRIVATE CONTACT to your radio.  Make sure its "Private Call" and not "Group Call".  The talk group you will send messages to is 262993.

Experiment with sending commands such as just "help" or "wx gps" or just "gps"

For the "wx gps" command to work, you need to make sure you are actually receiving a GPS signal and your radio should have the globe icon. If it has a red cross through it, it will not work.

Some thoughts you may want to consider when putting things related to sending text message include:

• Spending time in the CPS program to set quick keys, short message shortcuts and other related things you may see a need for. 

• Setting up a text message only zone or dedicated channels for use with your hot spot.  Not only can you now send text messages to get weather information, you can also set up a home GPS location to see a bearing and distance from anywhere by using the "gps set" and "gps home" commands. 

• Creating channels that have GPS enabled or disabled depending on what you want to do and to conserve battery life. 

Setting Up Your Hot Spot & Brandmeister

The already linked to article already goes into getting Brandmeister set up for use, so please have another look. 

One thing I discovered also is that it may be good to create a few GPS systems in your CPS for different use cases. Most radios allow multiple GPS profiles to be created and linked to different channels with different frequency and talk group destinations. 

There was a reason the noise in the video sounded like a train station. I was actually at the
Croton-Harmon Amtrak/MNRR station waiting for a train! 

What good is GPS anyway on the radio?

If you are a ham involved in EMCOMM related activities or have experimented with APRS, you may know that the different radios like the Icom ID-51, Kenwood TH-D72, TH-D74 and Yaesu FT-1 and 2 radios have built in GPS. All can give you distance and bearing to other stations also using APRS. 

What a GPS enabled DMR radio allows is the ability to translate your coordinates into the closest by physical address. This works by sending your GPS coordinates to the server that makes this all work and compare that to Google maps. Having the real life address sent back to your radio can be very helpful.  This is what happens when sending just "gps" to TG 262993.

Wrapping it up...

A lot more can be said about this, but what fun is reading even more.  Go play with that radio and talk about it with your fellow ham radio operators on appropriate nets, talk groups and in person.

Some favorites of more "tech forward hams" includes:

• Different organized nets found on the HVDN Activity calendar

• Talk group 31368 (Mid-Hudson Valley), 31428 (RF-IT) and many others...

Why Update To Pi-Star Update 3.14.3?

Most of the folks involved with HVDN agree that DMR is the digital voice mode that is spurring on massive growth in the hobby compared to Yaesu Fusion (C4FM) and Icom D-Star (GFSK) digital modes.

This HVDN article talks about Pi-Star
version 3.14.3 and its new cross mode features

Other digital voice modes that amateur radio operators are experimenting with include NXDN and P25.  While Fusion and D-Star were developed just for amateur radio use, DMR, NXDN and P25 all started life as commercial standards.  DMR was the first to see "ham grade" equipment for sale and truly sparked the digital growth we see today.

DMR is an open standard and many new vendors took advantage of this and started to offer radios at budget price points to spur experimentation with radios marketed directly towards the amateur radio community.   Traditional "ham equipment manufacturers" such as Yaesu and Icom pretty much missed the boat by continuing to push closed standards, with Icom having a very high licensing rate of its D-Star technology built by the Japanese Amateur Radio League almost 20 years ago. The only vendor who paid to get on board with Icom's D-Star is Kenwood with its 2016/2017 released $500+ TH-D74 radio.  Limited options and expensive equipment has kept many away from D-Star as a result.  Yaesu has fared a little better, but really not by much until recently with new affordable equipment.

All These Acronyms...

There is a comparison of the different modes mentioned above at the bottom of the "Basics of DMR" page on HVDN for those interested in more details as it gets confusing quickly for some people.

Because of all these different digital modes, different radios can not communicate with each other and take advantage of benefits and featured offered by digital technology compared to analog FM or NFM. Analog FM equipment is what has been the dominant amateur choice of non-HF radio for at least 40 years and digital migration is kicking and screaming its way into the amateur radio community. A universal digital standard is needed to truly replace FM.

Your very own repeater? Sort of...

The SharkRF OpenSpot was the first "hot spot" type device to provide cross digital mode support.  What this meant was a DMR based radio could talk on the D-Star network to other users with D-Star radios.  It also provided the ability for a Fusion radio user to talk on parts of the DMR network.

SharkRF Openspot was the first cross mode capable hot spot
device to see mass adoption by amateur radio operators

With DMR radios such as the TYT MD-380 or Radioddity GD-77 costing less than $100, it gave many amateurs a taste of what 80,000+ individual users already registered to use and also be able to talk to those with just Yaesu Fusion or Icom D-Star Equipment to see if they are missing anything.

Converting analog FM repeaters is not always the best option for those looking to add digital repeater capabilities to a specific area, so "hot spots" have found a unique niche to fill the gaps while owners of great sites for repeaters decide what to do when thinking about what digital modes to support for wide area coverage to eventually replace much of the FM based repeater infrastructure.

One of the latest "hot spot" devices provided by a community of developers. This MMDVM board
provides simultaneous transmit and receive or "full duplex" operation. It is like a "mini repeater" 

Pi-Star & 3.14.3

Another "hot spot" type of device based on open source design is sometimes known as the ZUMspot, JumboSPOT, ChinaSPOT and a number of others.  The team behind Pi-Star took somewhat more "scary" command line interfaces and made things easier by way of nice visual interfaces. These all mostly run a user interface called Pi-Star and the latest revision does something very interesting.

Version 3.14.3 allows anyone with a Yaesu Fusion radio to also communicate over DMR, NXDN and P25 now. This is pretty monumental where now that Yaesu has some lower priced new Fusion radios such as the dual band hand held FT-70DR or higher powered mobile FTM-7250DR, users an now use the inexpensive Pi-Star driven hot spots to connect with users of NXDN and P25 plus of course those on DMR. It also lets someone who may have purchased surplus commercial NXDN or P25 radios communicate over DMR or Fusion.

Turn in 1000 Feet: Excitement Ahead

Could these largely community and developer driven efforts be just what some of the more well known amateur vendors need to take advantage of?  Notably absent is any form of Icom D-Star anything in this latest revision.  Kenwood sells commercial NXDN equipment as well as P25.  Icom also sells commercial P25 equipment.  Yaesu's sister brand, Vertex, also has P25 equipment on the market.

One great example of a community member working with a commercial vendor is Ty,  KG5RKI who has alternate firmware available to increase features in certain radios.  Retevis partnered with him to officially support his work.  Will we see Icom, Yaesu, Kenwood or even Alinco take a similar approach?

Could DMR just be the entrance ramp towards a NXDN or P25 amateur future?

All these digital modes also do much more than just transmit voice. They can also be used to share GPS location and text messages in the same narrow frequency bandwidth used, some at the same time as voice communication.

From just May of 2017 to today,  by May of 2019 it should be interesting what else continues to see development and what commercially made equipment comes to market.

Updating to the latest 3.14.3 release is as easy as logging into your pi-star interface, going to "expert" mode and then to the SSH function.  After providing username "pi-star" and your password or default "raspberry",  type in "sudo pistar-update" and then after that completes, run "sudo pistar-upgrade"

Please note that you may need to modify certain hot spot boards to allow firmware upgrades, but you should find no shortage of those with knowledge to help you along the way.

Sample Resources

• Live Discussion: Have a look at the HVDN Net & Activity page 

• Social Media:  Facebook has a number of users groups such as JumboSpot, MMDVM & Digital 

• Local Discussion:  Local Hudson Valley DMR repeater directory (always under construction)

• In Person:  HVDN will start having in person meetings in Rhinebeck, NY later this summer once the location completes construction.

Join HVDN for FREE for the first year. Details here.

Field Strength Meter Monday: 3 Real World Applications For A F.S Meter

Last week saw the first article in the "Field Strength Meter Monday" series with a general overview.

Here are three practical applications to use any type of relative or calibrated RF field strength meter for.

• Check antenna radiation patterns
• Measure approximate transmitter power power or antenna efficiency
• Locate hidden transmitters

Which way does your antenna work best?

From a simple dipole for HF frequency operation, to directional beam antennas at UHF ranges, knowing which way your antenna is sending out the most RF energy is helpful to know.

Using a simple relative field strength meter will help you make your own charts somewhat accurately and very inexpensively. 

While the RF source being measured transmits a signal, the relative field strength meter will show a measurement that can be plotted on a piece of graph paper.  As you walk around the transmitting antenna with your field strength meter and note the readings, you can arrive at a chart like the one pictured to better understand your antenna characteristics.

Is my radio transmitting?

A relative field strength meter will also provide some idea as to if your radio is actually transmitting. This may be helpful to know if you hear other stations, but they do not hear you. Some radios will indicate a signal is being sent or tell you how much power it is supposed to be transmitting, but how do you know that for sure?

Using a relative field strength meter wont show you any calibrated power output measurements. For that sort of testing, a watt meter that measures specific levels of RF energy is needed, but that only shows actual RF power output and not how well the antenna is projecting your signal. A watt meter also needs to be connected inline with the transmitter and antenna. A field strength meter does not. 

Perhaps you want to see how well a new hand held radio transmits with the included antenna and another one purchased as a premium accessory? 

You can use a relative field strength meter to see which antenna works best and see how much of a difference you really get when changing from "extra low power" to "low power" and then to "medium" or "high" power output when using different antennas.

Showing the transmit output levels on the Kenwood TH-D74. The manufacturer claims 5 W, 2 W, 0.5 W and 0.05 W on the 3 bands the radio operates on which is 144, 220 and 440 MHz.

Where is that signal coming from?

A relative field strength meter can also be used to find very close by transmission sources.  Using a simple whip type of antenna will help the user find the signal source within a few hundred feet or less depending on how the relative field strength meter was designed.

If combining some form of directional antenna with a relative field strength meter, that creates an even more interesting tool for finding the strength of a signal as well as the direction from which it is coming.  This combination forms a basic radio direction finding tool that is inexpensive and easy to use.

Whats Next?

Next Monday, HVDN will introduce an updated relative field strength meter that blends both analog and digital technologies to create a very interesting tool with even more potential applications.

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Please subscribe to HVDN Notebook for additional details on the Field Strength Meter Monday series and other great content along the way too.

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Your Next Antenna Project: Upgraded Space Station Communications

This came up on the weekly North American astronomy net and now I know what my next antenna project will be. Not sure if NASA will be willing to share the plans with me or not though. 😉

Here is a nice article from April 27th 2018 with more detail.

NASA Upgrades Space Station Emergency Communications Ground Stations

Since the launch of the International Space Station’s first component in 1998, communications infrastructure has been critical to the station’s success and crew safety. NASA is currently implementing upgrades to very high frequency (VHF) communications ground stations that backup the station’s primary communications system, the Space Network, and communicate with Soyuz spacecraft when out of Russia’s range.

NASA’s VHF ground stations provide two-way, audio-only communications and transmit over two frequencies, VHF1 and VHF2. VHF1 is used for emergency communications with the International Space Station. VHF2 communicates with Soyuz spacecraft.

Russia also operates a VHF network independently from NASA's. The combination of the two networks ensures VHF communications are available on every orbit of the space station and Soyuz.

The space station hosts two VHF1 antennas, 180 degrees apart. They flank the Zvezda Service Module, an early Russian contribution to the station that served as an early cornerstone for its habitation. Astronauts and cosmonauts can communicate with mission control from any module of the station via VHF1.

“Maintaining the availability of utility-like communications between the crew and the ground is paramount to enabling mission success and ensuring crew safety,” said Mark Severance, Human Spaceflight Communications and Tracking Network director. “The NASA VHF network, in combination with the VHF network operated by our Russian partners, does just that.”

Under normal circumstances, the station relies on NASA’s Space Network, a series of Tracking and Data Relay Satellites in geosynchronous orbit. The network provides near-continuous communications coverage between the station and mission controlcenters around the world who make sure the station’s systems function properly. The Space Network also enables the transmission of high-resolution science data, ultra-high definition video and special downlinks like student contacts with astronauts. VHF1 would only be used in the unlikely event that the space station was unable to communicate via the Space Network.

Russian Soyuz spacecraft sport a single VHF2 antenna towards their tail. Russia uses VHF2 as their primary system for voice communications from launch at the Baikonur Cosmodrome in Kazakhstan to docking with the space station and upon undocking and returning to Earth.

On most Soyuz missions, the spacecraft docks with the space station prior to exiting Russia’s VHF network coverage. The same is true on return to Earth. However, on Soyuz missions that require a longer, 34-orbit rendezvous, the NASA VHF network stands by to provide emergency communications while the Soyuz is outside of Russia’s range, orbiting over the continental United States. NASA’s VHF network could also provide emergency communications in the event a problem required the Soyuz to stay in orbit for an extended period of time.

NASA’s upgrades to VHF network ground antennas, currently underway, involve improvements to numerous electronic components and installation of new software for tracking the space station and Soyuz. Additionally, new antennas at the ground stations, able to operate at VHF1 and VHF2 simultaneously, will add redundancy to the network so that if one system fails, the other system will be able to take over immediately.

“The purpose of these upgrades is to ensure the VHF ground stations remain a robust capability for backup and emergency communications,” said Severance. “The addition of redundancy, the ‘belt and suspenders’ approach, is particularly important given that these systems would only be employed due to failure of the primary space station communications system or an emergency onboard the Soyuz.”

NASA maintains VHF ground stations in two locations: Wallops Flight Facility in Wallops Island, Virginia, and NASA’s Armstrong Flight Research Center in Edwards, California. These ground stations are strategically placed to maximize contact with the station and Soyuz as they orbit above North America. The Russian VHF ground stations are located throughout Russia, providing contact as the space station and Soyuz orbit above Asia and Europe.

NASA’s VHF system is managed by NASA’s Goddard Space Flight Center’s Exploration and Space Communications projects division. NASA’s Space Communications and Navigation program office provides programmatic oversight to the network.

Banner image: The International Space Station. Credit: NASA

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By Danny Baird
NASA’s Goddard Space Flight Center, Greenbelt, Md.

Last Updated: April 26, 2018

Editor: Rob Garner

https://www.nasa.gov/feature/goddard/2018/nasa-upgrades-space-station-emergency-communications-ground-stations