BREAKING: New additions / extensions to the ZS Link Network in the Southern Cape! (Part 2)

Image:  DMR Repeater, Southern Cape  (Click on image for larger view.)

Great news!!  The first and currently the only DMR Repeater in the Southern Cape Area of South Africa is now on the air.  I hear you ask but what is all the fuzz about.  This is no big deal!  Well everybody is entitled to his own opinion in this regard.  For radio amateurs living in the Southern Cape it means that they have several more options to communicate with other radio amateurs locally and world wide.  Furthermore the addition of this DMR Repeater increase the size of the ZS Link Network even further.  Be as it may the Southern Cape now have a DMR Repeater on the air!

Tell me more about a DMR Repeater.

From the on-set let me make it clear - DMR is far from being complicated to setup and operate.  You will find an abundance of information on the Internet that will assist you in setting up / programming your radio etc.  And please give DMR a try without lending out your ears to those who do not like digital radio.

A

DMR (Digital Mobile Radio) repeater  is a specialized two-way radio system used in amateur radio to extend communication range by receiving a digital signal and re-transmitting it at higher power, often from an elevated location. Unlike traditional analog repeaters, DMR repeaters use digital technology based on the ETSI DMR standard, which allows for clearer audio, enhanced data features, and highly efficient use of radio spectrum. 

Key Technical Concepts

 

DMR repeaters differ from analog systems due to several "digital magic" features that allow multiple conversations to share the same frequency: 

• Time Slots (TS): DMR uses TDMA (Time Division Multiple Access) to divide a single 12.5 kHz channel into two alternating time slots. This effectively allows two simultaneous, independent conversations on the same frequency without interference.
• Color Codes (CC): Functioning like digital CTCSS/PL tones, color codes (range 1–15) act as a "gatekeeper". Your radio must be programmed with the correct color code to access and trigger the repeater.
• Talkgroups (TG): These are virtual "channels" or rooms within the digital network. They allow users to join specific groups (e.g., local, regional, or worldwide). Most repeaters assign certain talkgroups to specific time slots to keep traffic organized.
• Network Linking: Many DMR repeaters are connected to the internet through global networks like BrandMeister or DMR-MARC. This allows a ham with a simple handheld radio to talk to other operators across the globe via their local repeater.

Equipment and Setup

 

Using a DMR repeater requires more advanced configuration than analog FM: 

• DMR Radio: You must use a radio specifically designed for DMR (e.g., Anytone, TYT, Radioddity). Most of these also support standard analog FM.
• DMR ID: To transmit on most networks, you must register your callsign at RadioID.net to receive a unique digital identification number.
• Codeplugs: Programming a DMR radio involves creating a "codeplug"—a file containing frequencies, color codes, time slots, and talkgroup lists for the repeaters you wish to use.

Benefits Over Analog

• Spectrum Efficiency: Doubles the capacity of a single licensed channel.
• Superior Audio: Digital processing filters out static and background noise, maintaining clear audio right up to the edge of the coverage range.
• Battery Life: Because the radio transmits in short bursts (sharing time slots), handheld batteries typically last longer than in continuous analog mode.
• Advanced Features: Supports text messaging, GPS location sharing, and private calling.

Are you looking for the DRM Repeater Information to setup your DMR radio / station?

 

Key Technical Parameters & Setup

• DMR ID: A unique identification number assigned to your call-sign, necessary for network access.
• Color Code (CC): Similar to PL tones in analog, ranging from 0–15.
• Time Slots (TS): DMR divides a 12.5 kHz channel into two distinct slots (TS1 and TS2), allowing two separate conversations on one frequency pair.
• Talkgroups (TG): Used to direct traffic to specific groups of users.
• Code Plug: Programming software is required to configure these settings into your DMR radio.
  

 

ZS1I DMR Repeater Information:

Mode: DMR

Band:  70cm
TX Frequency:  438.262500 Mhz
RX Frequency:  430.662500 Mhz
Radio Mode:  Duplex
Talk Group (TG): 65522
Colour Code:  1 or 2
Time Slot:  1
Band Width:  12.5 khz
TX Time Out Time:  3 Minutes
TX Power: 10 Watt 

Site:  ZS1I Station Shack, Heiderand, Mossel Bay

License: ZS1I Amateur Radio License

Note:  This repeater is not located on a remote site which requires a separate license.  The repeater will only be available daily from 05h00 SAST to 21h00 SAST.  This allows the owner to monitor and control the repeater while it is on the air.  This repeater is linked to the ZS Link Network (Analog Repeaters / Simplex Link Radio / Echolink / SVXLink / AllStar / South Cape Reflector) via the ZS1I DMR Bridge. 

Requests and Reminder:

IMPORTANT:   PLEASE leave a "6 second delay" between replying to a station to allow ALL the systems to reset and connect.

Please note this is a global network and you will be transmitting on RF all over the world.

It is extremely important that you spend time ensuring your audio levels are correct before connecting and using the DMR Bridge, DMR Repeater and the ZS Link Network.

Correct operating procedure is a distinct characteristic of Amateur Radio.  It’s important that you convey to the public, and to new radio amateurs, the image that Amateur Radio Operators are courteous, patient, and really know what they’re doing.  A friendly style is great, but we also need to operate professionally.  You never know who may be listening.
 
Do not cause intentional interference, to links, repeater, hubs, nodes or conversations on the network.  Intentional interference is not only heard locally but World Wide.  Just remember that intentional interference can today easily be traced to your call sign as all connecting RF and Digital stations leave an identifiable script in a log file.

Finally:  

Re-structuring and expansion of the ZS Link  Network is an ongoing process and the network is getting bigger and bigger with the time.  Do not panic we will not leave our local radio amateurs in the cold.  I recently overheard a conversation were a radio amateur indicated that the ZS Link Network is not for local use but caters more for world wide activity.  This is far from the truth.  If you not certain how the ZS Link Network functions  you will find more info on the ZS Link Network Blog Pages.

Feedback regarding the DMR Repeater and ZS Link Network can be forwarded by clicking HERE.

 

Images:   Click on images for larger view.

 

 

Building Low Budget Antennas - DIY Delta Loop Antenna for the 6 Meter Band ( 50 - 54 Mhz)

In this article I will describe how I built my version of the 6m Delta Loop Antenna for use with a 6m Beacon.  But first let's look at some information relating to the Delta Loop Antenna.

A delta loop antenna is a high-efficiency, full-wavelength, triangular-shaped wire antenna known for low-noise, excellent DX (long-distance) performance, and low-angle radiation. It is typically fed with coaxial cable using a 4:1 balun or a 75 Ohm Quarter-Wave Transformer for impedance matching, configured with one apex up or down, and can be horizontally or vertically polarized depending on feed point placement. 

Key Features and Design Aspects:
 
• Structure: A full-wave loop (total length in meters = 306 divided by Frequency in Mhz
  
  ) formed into a triangle.
• Versatility: It can be configured as apex-up or apex-down, or even laid flat (horizontal) for NVIS (local) communication.
• Polarization: Feeding the antenna at a corner or the bottom side generally results in vertical polarization, ideal for DX. Feeding it at the center of the base can produce horizontal polarization.
• Performance: Offers low-noise reception compared to dipoles, making it ideal for urban environments.
• Impedance: The feed point impedance is roughly 100-200 ohms, often requiring a 4:1 or 2:1 balun or 75 Ohm quarter-wave transformer for a 50-ohm match.
• Multiband Capability: Can be used on harmonics with a tuner, though it is fundamentally a single-band antenna.

Key Benefits of Delta Loop Antenna:

 A Delta Loop antenna is quieter, providing roughly 2–3 dB more gain than a dipole, and offering excellent, low-angle radiation for DX (long-distance) contacts.   They are versatile for mounting, often requiring only one high support point, and are less sensitive to ground quality than vertical antennas. 

• Lower Noise Floor: Because they are closed loops, they are much quieter and less susceptible to environmental RF noise compared to open-ended antennas like dipoles or verticals.
• Superior Gain and Performance: Delta loops offer higher gain (roughly 2-3 dB) compared to a standard dipole. They function effectively as stacked, bent dipoles, especially when oriented vertically.
• Excellent for DX (Low-Angle Radiation): When vertically mounted, they produce a low-angle radiation pattern, which is ideal for long-distance communication.
• Easy Installation: They generally only require one high support point (such as a tree limb or mast) to hang, making them easier to deploy than horizontal loops or complex beam antennas.
• Wide Bandwidth: They are typically broad-banded and often allow for operation across a wide SWR range without a tuner.
• Versatile Polarization: Depending on where they are fed (top, bottom, or side), they can provide either horizontal or vertical polarization.
• No Radial System Required: Unlike traditional vertical antennas, a delta loop does not require a complex, extensive ground radial system.
• Multi-band Potential: A single full-wave loop can be used on its fundamental frequency as well as higher harmonics, increasing its versatility.

Key Disadvantages of a Delta Loop if not installed correctly: 

Delta loop antennas, while efficient, have several disadvantages, including requiring significant height and complex, multi-point support structures.  They are generally limited in multi-band performance and can be very narrow-banded, making them less versatile than other antennas. Additionally, they are highly dependent on ground height for optimal, low-angle performance.

• Complex Installation: They require more involved installation compared to dipoles, demanding a tall, sturdy support structure.
• High-Angle Radiation/Limited DX: If not placed high enough (ideally at least a 1/2  wavelength above ground), they can favor high-angle, NVIS (Near Vertical Incidence Sky-wave) propagation rather than the low-angle radiation needed for long-distance (DX) communication.
• Narrow Bandwidth: They often have high-Q, resulting in a very narrow operating bandwidth, which can limit performance outside of the designed frequency.
• Limited Multi-band Performance: While they can work on harmonics, their performance, impedance, and radiation patterns can become unpredictable, making them less ideal for multi-band use. 
• Large Size & Wind Load: They are physically large, increasing wind loading and making them more susceptible to weather damage.
• Impedance Mismatch on Harmonics: Their feed point impedance can swing wildly on frequencies other than the primary design frequency, requiring a good antenna tuner.

In any project one needs a plan, diagram, guidelines and information.  At least that is my way of constructing any DIY Project.  I research the project thoroughly before I start any work.  I did exactly this before I started on this project.

Now the Internet is your friend but can also be your enemy if you just jump in and start constructing the first plan you find.  I was looking for the dimensions of a DIY 6m Delta Loop Antenna and ran into an abundance of information which included a calculator.  

The dimensions for the antenna was calculated using the free  Calculator program available HERE ). I set my frequency to  50.000 MHz as this antenna needs to resonate in the 6m CW beacon frequency allocation section. The resulting calculations is shown in Image 1 and 2 below. 

Image 1 and 2  (Click for larger view.)

The calculator was fed with the information to the left of the antenna drawings above.  Needless to say my dimensions differ slightly from those provided by the calculator.  This is mainly due to several inputs that changed due to the way I constructed the antenna and also the parts I used.  The calculator however provides good information when building a Delta Loop Antenna.  I decided to use the good old antenna formula to calculate the dimensions of the antenna I constructed.

Image:  Final calculator measurements  (Click on image for larger view.)

Formula for full-wave loop antenna:

Full-Wave in Meters   =  306  /  Frequency in MHz

       6.12 meter            =  306  /  50.000 MHz

       6120 mm              =  306  /  50.000 MHz

Formula for Impedance Matching Transformer:

Quarter-wave matching section length in Meters  =  75* cable's velocity factor / frequency in MHz

       99 cm      =    75 x 0.66  /  50 000 MHz

       990 mm   =   75 x 0.66  /  50 000 MHz

Materials that I used:

6100 millimeter x 2 mm PVC Insulated Copper Wire

2200 millimeter x 25 mm PVC Electrical Conduit Pipe

2200 millimeter x 22 mm Wooden Dowel (Fits into the 25mm  PVC Conduit Pipe to stiffen the pipe.)

2 x 25 mm PVC End Caps

3 x 10 mm Stainless Steel Self Tapping Screws.

1 x SO239 Connector

2 x Electrical Eye Lug (Terminal)

2 x 45mm x 5mm Stainless Steel Bolts + Washer + Lock Nuts

2 x 15mm x 3mm Stainless Steel Bolts and 2 x Lock Nut

2 x Stainless Steel TV - U Clamps

2 x Stainless Steel Pipe - U Clamps

1 x 150 mm x 100 mm x 5mm Aluminum Flat Plate to mount PVC Pipe to the mast for support.

1 x 1.5 m RG59 CU Mil-Spec Coax Cable (75 Ohm)

8  x 300mm x 4.6 Hellermann Cable Ties

6 meter 3 mm Nylon Rope to support the PVC Pipe fitted tot the mast

Odds and Sods:

Hot Glue Sticks

Self Amalgamating Tape

Solder

Solder Paste

Marine Silicone Sealant

Heat Shrink Tubing

 

Tools:

 

Metal Punch

Drill

Various Drill Bits 3mm - 8mm

Hack Saw 

Hot Glue Gun

Soldering Iron

Screw Driver (Small flat)

Alen Keys 

Spanner Set

 

Test Equipment:

 

SWR Meter

Antenna Analyzer (If you have one but not compulsory)

Amateur Radio Transceiver

Coax Patch Leads

Mast (Non conductive)

Coax feed line cable  12 m  RG58CU 50 ohm

Power Supply for Radio 

Building the Antenna:

My final dimensions is listed in the image below:

 

I am not going to go into detail how I constructed my version of the antenna. I will however describe my findings in constructing and testing the antenna.  The images below provide good detail of how I constructed the 6 m Delta Loop Antenna.

My build observations and findings:

Pointing Up or Down:  The Delta Loop can be orientated so that it is pointing up or down. The advantage of having the apex at the top is that it may be be more mechanically secure as the antenna hangs from a single point. The advantage of having it pointing down as in the diagram above is that it means the maximum current part of the antenna is slightly higher above ground level.

Mast Material:  The support for the Delta Loop should be a PVC or Glass Fiber pipe or a similar material. A metallic mast running through the center of the Delta Loop will probably de-tune it.

Feed point impedance and coaxial matching section:  The feed point impedance at the design frequency is about 100 ohms, so full wave loops are often fed with an impedance-matching section made from a piece of 75 ohm RG59 coaxial cable, one quarter wavelength long.

Length of an impedance-matching section with 75 ohm cable with a velocity factor of 0.66:  The most important thing with the matching transformer is the length of the shielded part.  It must be 990 mm long.  Here is how I cut the transformer cable (RG59).  Cut a piece with a length of 1050mm and remove 30mm of the PVC-coating from each end.  I then wound the braid together and remove the small piece of isolation from the center.  I tinned the wires and then constructed the "dummy balun" from 40mm PVC pipe and end caps plus a few screws, washers and bolts.   See images below of how I built the matching transformer.

The wire for the loop is simple 2 mm PVC coated wire used in household electrical wiring.  Each end of the antenna is fitted with an electrical eye lug that is screwed to the matching transformer.

The antenna is horizontal polarized with a final SWR of 1.15  :   1 @ 50 Ohm Impedance.  The antenna wire is adhered to the PVC pipe and top apex by means of cable ties.

The antenna is not yet at it's optimal height.  I am waiting for my son to assist me in adding the second mast section to bring the antenna to a height of  at least 9 meters.  This article will be updated with images when I extended the mast length.

The wooden dowel is kept in place by 3 Stainless Steel Self Tapping Screws while the matching transformer is kept in place by 3 cable ties.

The two nylon lines running downwards towards the mast is to keep the 25 mm PVC pipe secure during strong wind storms.  You need not install these but where I live we experience gale force winds from time to time.

Preliminary Tuning Result:  1.37 : 1 SWR @ 49.9 Ohm Impedance

Final Tuning Result:  1.15  :  1 SWR @ 50 Ohm Impedance

Good enough for me!!

Use of the 6m Delta Loop Antenna:

This antenna will be used for the 6m CW Beacon that are in the final stage of construction.  More on this in a future article.

Finally:  

The 6 m Delta Loop is a pretty easy antenna to construct and most of the material can be obtained at a local hardware store. It's an easy way to get an antenna with a small amount of gain well above ground level.

Images (Click on images for larger view.)

The ZS Link Network description according to AI!

The Amateur Radio ZS Link Network in the Southern Cape is a large, interconnected infrastructure of VHF and UHF Repeaters, Nodes, VOIP, Reflectors, DVSwitch Bridge etc. managed by local amateur radio operators with local operators associated with the  ZS Link Network Group. These systems enable local and long-distance communications via FM voice (Analog), Digital Radio (MMDVM) and Voice over Internet Protocol (VoIP), covering large parts of South Africa and even World Wide.  The Network acts as a bridge for diverse systems—including both analog and digital modes—enabling operators to connect regardless of their specific hardware.

Key Features of the Network:

• Coverage: The network stretches from the West Coast to the East Coast and from the North of the country to the South of the country and even World Wide.
• Interlinking: Repeaters/Simplex Links are connected via the Internet, allowing a user to be heard in South Africa and World Wide.
  
• Control: The links between different repeaters/simplex networks can be enabled or disabled using various methods.
  
• Management: It is managed by the ZS Link Network Group (ZSLNG), which includes radio amateurs from various radio clubs in South Africa.

Core Functionality:

• Supported Systems: AllStar, SVXLink, DMR (BrandMeister), Yaesu System Fusion (YSF), EchoLink and AREDN
• Operating Guidelines: Because pushing a PTT (Push-To-Talk) button can open 250 to 300 transmitters simultaneously when linked worldwide, users are asked to keep individual conversations (QSOs) under 15 minutes and leave a 6-9 second gap between overs.
  
• Community Standards: The network prohibits obscene language and discourages discussions on sensitive topics like politics or religion.

Southern Cape Context:

• Nodes: The network links areas like Still Bay, Mossel Bay, George, Knysna, and the broader ZS zones and overseas networks.
• Usage: It is used for weekly, international, or local nets (discussions), as well as emergency communications in the Southern Cape.

 Common Frequencies in the Southern Cape Region:

• 145.625 MHz (Aasvoelkop): Provides wide coverage. Require 88.5 Hz CTCSS tone.
  
• 145.750 MHz (Stilbaai Repeater):  Mainly local coverage. Require 88.5 Hz CTCSS tone.
• 145.725 MHz (Stilbaai Test Repeater): Test repeater to be installed at a suitable site in the Southern Cape
• 145.550 MHz  (Mossel Bay Simplex Link): Mossel Bay Area coverage.  Require 88.5 Hz CTCSS tone.
• 430.662500 MHz (Mossel Bay DMR Repeater):  Mainly local coverage.
  

The ZSLNG regularly publishes the status of these repeaters / links on their Blog available HERE. 

 

Connection Details:

Operators can join the ZS Link Network using the following specific Southern Cape nodes.

• AllStar Link: Nodes 49355, 467653.
• EchoLink: ZS1SB-L, ZS1I-R, ZS1DRP-R.
  
• DMR: BrandMeister TalkGroup (TG) 65522.
• SVXLink Reflector (SouthCape) :  ZS6CMO
  

Additional Resources:

• The 625 WhatsApp Group: Die 625 - 6 uur half 5 span
  

All infrastructure is maintained by the ZS Link Network Group (ZSLNG)

Contact details of persons responsible for the maintenance of Repeaters, Links, Nodes and Interfaces in relation to the ZS Link Network Group:  Click HERE.

ED.  Must say that AI did not do to bad describing the ZS Link Network and also creating the images. 

BREAKING: New additions / extensions to the ZS Link Network in the Southern Cape! (Part 1)

Some might have noticed that the editor of this article was not very active on the ZS Link Group Nets lately. Well there was good reason for this.  I have been working on several projects relating to the ZS Link Network the past few weeks.  I do have the pleasure to announce a new addition  / extension to the ZS Link Network in the Southern Cape.  Before I announce the new "KID" on the block, it is important to first announce a few important changes relating to the new add on.

Changes to the ZS1I DMR Bridge Node:

The DMR Bridge has been in operation on the ZS Link Network since 31 August 2023.

The following changes were made to the DMR Bridge on the 7 March 2023 and radio amateurs that uses the ZS Link Network must please take note of the changes:

1.  Node Number:  467652

2.  Talk Group (TG):  IMPORTANT - Changed to 65522

3.  New Supermon Name:  ZS1I DMR Repeater TG65522 Mossel Bay, ZA 

 

Now what is this all about?

DMR users must change to the 65522 Talk Group (TG) if they want to access the ZS Link Network via DMR.   

When the Bridge is active it connects the following applications/nodes together which is forming  a "Bridge".  Simply put it allows one person to talk on Echolink and the conversation will be propagated to AllStar and DMR and vice versa. 

Example:

Echolink  ####> Allstar ####> DMR and DMR ###> AllStar ###> Echolink

ZS1I-R Echolink ####> 49355  Allstar ####> DMR and  DMR ###> 49355 AllStar ###>  ZS11-R Echolink

The Bridge is also available to all the stations connected to the ZS Link Network and to those stations connected to each other. 

Benefits of setting up a DMR Bridge:

• Connecting (bridging) a DMR Repeater to AllStar, Echolink, SVXLink etc. 
  
• Useful for Emergency Communications
• Ad Hoc Connections
• Access to repeaters from other areas and modes (Hotspots)
• Creates activity on the VHF/UHF bands
• Extend the reach to other parts of the country and worldwide
• Allows analog users to TX+RX on DMR as many radio amateurs do not have a digital radio to operate DMR.
• Because you can and the software is freely available thanks to fellow radio amateurs
  
• Lends itself to experimentation
• Learn more (educational) about the workings of Digital Radio, Analog Radio, Nodes, VOIP, links, bridges etc.

Requests and Reminder:

PLEASE leave a "6 second delay" between replying to a station to allow ALL the systems to reset and connect.

Please note this is a global network and you will be transmitting on RF all over the world.

It is extremely important that you spend time ensuring your audio levels are correct before connecting and using the DMR Bridge.

Correct operating procedure is a distinct characteristic of Amateur Radio.  It’s important that you convey to the public, and to new radio amateurs, the image that Amateur Radio Operators are courteous, patient, and really know what they’re doing.  A friendly style is great, but we also need to operate professionally.  You never know who may be listening. 

 

Do not cause intentional interference, to links, repeater, hubs, nodes or conversations on the network.  Intentional interference is not only heard locally but World Wide.  Just remember that intentional interference can today easily be traced to your call sign as all connecting RF and Digital stations leave an identifiable script in a log file.

Finally:  

In Part 2 I will provide information of the new and only DMR Repeater in the Southern Cape Area of South Africa.  Re-structuring and expansion of the ZS Link  Network is an ongoing process and the network is getting bigger and bigger with the time.  Do not panic we will not leave our local radio amateurs in the cold.  I recently overheard a conversation were a radio amateur indicated that the ZS Link Network is not for local use but caters more for world wide activity.  This is far from the truth.  If you not certain how the ZS Link Network functions  you will find more info on the ZS Link Network Blog Pages.

Please note: The AllStar-Echolink-DMR Bridge and new DMR Repeater is currently in a experimental phase and might only be active at certain times of the day.  A full "how-to" will be provided in Part 2 on how to use the new DMR Repeater situated in Mossel Bay.

Down Memory Lane: What the heck was this Reboot Coffee Drink Event in the Southern Cape?

Please take note that this is a Down Memory Lane article.  I will publish a few articles in this regard in the future.  This event ended when Covid19 started and is not active anymore due to various reasons.  I hope our readers enjoy these articles from the past.  These events were great amateur radio events enjoyed by all!!

The short answer is:  It was “something” that works very well in the Southern Cape.  So much so that many of the participants  could not wait for this monthly event.

The short answer does not give justice to the event.  Herewith some more “meat around the bone”.

During a weekly coffee drink session in January 2019 between Johan ZS2I and Johan ZS1I we discussed the so call lack of amateur radio activity in the Southern Cape.  The idea  came from  Johan ZS2I that we should visit a local coffee emporium and invite all radio amateurs to come and drink a cup of good old coffee with us.  To make things short this idea became a reality and is now a regular event on the Reboot Amateur Radio calendar.

It is with great humbleness that I can now report that every event up to now resulted in an increase in attendees. The coffee drink event is open to all radio amateurs and prospective radio amateurs in South Africa.  We already had a few visitors from up-country that joined the events.

Do you only drink coffee?

No this is where the success story evolved.  As with the Reboot Amateur Radio Whats App Group we have set some guidelines. They are: 1. No club activities are allowed to be discussed at the event. 2. No amateur radio "politics" of any kind. 3. No country politics of any kind. 4. No religion discussions of any kind. 5. No bashing, barging or fight picking and foul language of any kind.  These guidelines solved a lot of past issues.  The coffee drink events are all informal and NOT a formal meeting of some sorts.

The main draw card is not the coffee but rather the “Rondomtalie/Round Robin”  Mini Lectures and Demonstrations.  Now what on earth is “Rondomtalie/Round Robin”?  I am not going to answer the question here but would rather refer you to future Down Memory Lane articles.

Now why mention all this here?  Do you try to brag?

No not bragging or boasting.  I received several requests from various regions that showed an interest in the format we use.  Some clubs are battling with attendance figures as in today’s life there are to many formal meetings.  Sounds familiar?    Now many has expressed their dislike in attending amateur radio club meetings. (NO PUN INTENDED)  A wide variety of radio amateurs would like to enjoy an informal get together without having to listen to formal club matters.  I post this topic in the event that other regions would like to follow our format.  Yes it is not for everyone but it is working exceptionally well in this part of the country.  After two hours I must intervene and try to close down the event as other members of the public might also want to drink coffee.  Interest by the public in what we are doing are now also becoming quite prevalent at the gatherings.  Hopefully this will draw new blood to amateur radio. Many radio amateurs that visited the events  expressed their dismay at the fact that the gathering only last two hours.

Finally:  This event is not a one man show!!  It is not about figures of how many attended but rather about camaraderie, friendship and meeting up with good friends.  It is also an escape from formal amateur radio meetings.  Something many dislike and one reason for not attending such meetings.


The success lies therein that without the participation of those present at the coffee drink, this event is surely to have failed but thankfully it is growing and amateur radio activity is once again on the increase in the Southern Cape.

DMR Activity on the increase via the ZS Link Network. What is a DMR Bridge?

Image:  DMR Dashboard - Activity this morning (Monday, 2 March 2026) via the DMR Bridge  (Click on image for larger view.)

Image:  AllStar Link Log - Activity this morning (Monday, 2 March 2026) via the ZS Link Network.  The DMR Bridge connection is visible second entry from the top. (Click on image for larger view.)

Above:  DMR activity on the 3 March 2026 during the SA DMR Net.

The AllStar-Echolink-DMR Bridge is active since the 8 June 2023 on the then Garden Route Hub Network and today still available to all the ZS-Link Network users via the ZS Link Network, Mossel Bay.  Now what is this all about?

It is quite simple.  When the Bridge is active it connects the following applications/nodes together which is forming  a "Bridge".  Simply put it allows one person to talk on Echolink and the conversation will be propagated to AllStar and DMR and vice versa.

Example:

Echolink  ####> Allstar ####> DMR and DMR ###> AllStar ###> Echolink

ZS1I-L Echolink ####> 49355  Allstar ####> DMR and  DMR ###> 49355 AllStar ###>  ZS11-L Echolink

The Bridge is also available to all the stations connected to the ZS Link Network and to those stations connected to each other.

Particulars:

The magic files are loaded onto the 467652 Allstar Node (Raspberry Pi 3(b)) which host the following software/Nodes:

•     AllstarLink Firmware for the Raspberry Pi  Node 467652
•     Install Private Node 1999 
•     Install  DVSwitch Firmware 
•     Create a Brandmeister Account

Further Particulars:

•  The AllStar Node runs as a Psuedo Node
•  AllStar Node 467652 is connected to the Private Node 1999 which is using the USRP channel driver.
•  the USRP channel driver talks to the DVSwitch program that is setup to communicate with Brandmeister TG
• When on your Brandmeister linked Hotspot or repeater (if applicable), if you talk on Talkgroup 91 you will be heard on AllStar 467652 and 49355 (when connected) and where ever is is connected to.
• AllStar Node 49355 is currently linked to Brandmeister Talkgroup 65511
  

Now why on earth would you setup a Digital DMR Bridge on an Analog AllStar Node and Echolink Node?

•     Useful for Emergency Communications
•     Ad Hoc Connections
•     Access to repeaters from other areas and modes (Hotspots)
•     Creates activity on the VHF/UHF bands
•     Extend the reach to other parts of the country and worldwide
•     Allows analog users to TX+RX on DMR as many radio amateurs do not have a digital radio to operate DMR.
•     Because you can and the software is freely available thanks to fellow radio amateurs
•     Lends itself to experimentation
•     Learn more (educational) about the workings of Digital Radio, Analog Radio, Nodes, VOIP, links, bridges etc.

Considerations:

• Audio quality between the networks
• Allstar Link has EXCELLENT audio quality
• Digital has no hiss

Control:

• Use private nodes to allow the maximum control

 How does it work:

• Stream conversion
• Audio and metadata converted from one format to another
• Adapters for each specific network  
• For Echolink to work ZS1I-R need to be connected to AllStar Node 49355.  The bridge runs on ZS1I-R.
 
Requests and Reminder:

PLEASE leave a "5 second delay" between replying to a station to allow ALL the systems to reset and connect.

Please note this is a global network and you will be transmitting on RF all over the world.

It is extremely important that you spend time ensuring your audio levels are correct before connecting and using the DMR Bridge.

Correct operating procedure is a distinct characteristic of Amateur Radio.  It’s important that you convey to the public, and to new radio amateurs, the image that Amateur Radio Operators are courteous, patient, and really know what they’re doing.  A friendly style is great, but we also need to operate professionally.  You never know who may be listening.

Do not cause intentional interference, to links, repeater, hubs, nodes or conversations on the network.  Intentional interference is not only heard locally but World Wide.  Just remember that intentional interference can today easily be traced to your call sign as all connecting RF and Digital stations leave an identifiable script in a log file.

Finally:  

Re-structuring of the ZS Link Network is an ongoing project.  Do not panic we will not leave our local radio amateurs in the cold.  I recently overheard a conversation were a radio amateur indicated that the ZS Link Network is not for local use but caters more for world wide activity.  This is far from the truth.  If you not certain how the ZS Link Network functions  you will find more info on the ZS Link Network Blog Pages.

Activity on the DMR Bridge is a daily occurrence.  The DMR Bridge is permanently connected to the ZS Link Network via Echolink and AllStar. If you have DMR equipment connect to the 65511 TG or via ZS1I-R Echolink or 49355 AllStar Link and talk to us via DMR. I hear you say but I do not have DMR equipment.  No problem just download DroidStar from Play Store on your phone, install and then talk via DMR to the World.  In the last few weeks there was a increase in activity on the DMR Bridge