Technical Coordinator
Jeff Kopcak, K8JTK
One thing about ham radio, there is no shortage of linking systems. Most are familiar with
analog linking like EchoLink and IRLP but there were less popular ones such as WIRES and
eQSO. Digital has many more options because when someone disagrees with an
implementation, they make another. This allows for options but leads to fragmentation and
incompatibilities. The AllStar Link project can link different infrastructure systems together
or be a completely independent system. I learned about this linking system and accepted
a challenge from one of the Technical Specialists.
Some of your Technical Specialists and I have this spirited debate about Motorola radios.
They are correct claiming Motorola radios can take a lot of beating and keep on ticking. Not
quite Timex but close. Commercial radios are designed to endure extreme conditions. Think
police trying to wrangle a criminal or fire fighters in extreme temperatures of a working fire.
You don’t want to worry about your primary line of communication being destroyed in the
process. Ham grade gear won’t stand up to that kind of use and abuse. Older Motorola
gear is very popular with hams as dependable FM repeaters and for use on 900 MHz. They
make great repeaters because they have excellent adjacent channel rejection (selectivity)
which minimizes interference from other transmitters.
My counter is most of this gear is not capable of VFO, a must when working with other
agencies and not familiar with their frequencies. Some models are better than others
getting them to transmit in the ham bands if the radio’s band split is just above or below the
ham bands. A common practice is to bring a radio with the 450- 512 MHz split to transmit in
the 440-ham band. Aligning the radio is often needed because it has drifted off frequency. A
service monitor or RIB (Radio Interface Box) cable are needed. Everyone should have a
service monitor or scope, few do. Many older radios require a PC with a serial port and/or
DOS application to be programmed. Serial ports are becoming harder to find on computing
devices. I’ve heard USB to Serial Port adapters work, for the most part, with the help of
DOSBox. DOSBox is an emulation of DOS that works on modern operating systems.
Primality designed as a tool to run DOS-based games but it also works for other DOS
applications. To download a legitimate copy of the Motorola CPS programming software, the
subscription cost can get ridiculous. A Radio Reference thread indicated it could range from
under $200 to $400 with an increase last year for MotoTRBO equipment. As a former
programmer, pirating doesn’t support developers and doesn’t allow the company to put
money back into developers and adding features. If you’re kind enough, someone with a
subscription maybe willing to program the radio for you or find a ham-friendly radio dealer
willing to do the same or sell the software at cost. Pro tip, don’t ask about pirated software
in the RR or in other forums.
Out of this debate came a challenge from Bob – K8MD to try out a Motorola radio. I
eventually found a project where I need a radio but the programming wouldn’t change
often. I did a lot of reading and research on BatLabs and Repeater Builder which are great
resources for repurposing commercial radios and building repeaters. The used market is
where these radios will be found. Advice from those sites will be very useful in not getting
ripped-off, especially decoding the radio model number. My project was to setup an AllStar
Link node and it was a perfect time to try a Motorola CDM1250.
AllStar Link, often called AllStar, is an Amateur Radio linking system on a Linux computer,
running the opensource PBX telephone switching platform called Asterisk. An AllStar
module called app_rpt turns Asterisk into a powerful, full featured, Ham Radio repeater
controller, and linking package. It is theoretically capable of controlling hundreds of nodes
at a time. Jim Dixon - WB6NIL (SK), developed app_rpt and is considered to be the father of
AllStar. Asterisk is typically used as a SMB (small/medium business) phone system.
Like other analog Voice over IP systems (VoIP), such as EchoLink or IRLP, it links radio
systems together. AllStar is flexible enough to link other infrastructures together as well.
The ability to make connections on any IP network makes AllStar decentralized, meaning it
doesn’t need to rely on other infrastructure. No central server for someone to pull the plug
resulting in a complete collapse of the network. The concept of a node in AllStar
terminology is a loose definition but they all run the same exact software. Node types are
generally defined as:
• Repeater: full duplex node and user functions accessed by DTMF
• Simplex node: half-duplex node, also with user functions available
by DTMF
• Remote Base node: a half-duplex, frequency agile HF, VHF, or
UHF remote base. Will not respond to DTMF on RF.
• Hub node: a common connecting point (similar to Conference or Reflector) with plenty of
Internet bandwidth to handle many connections at one time, has no RF connected
hardware Nodes can be public, private, or a combination of both. A public node would be
accessible by any other public node on the AllStar network and requires Internet access to
the AllStar infrastructure for the phonebook of public nodes. Private nodes can be limited to
select users or on a completely private network, like a mesh network, where you don’t want
many uses connecting over limited bandwidth links. These are great for connecting
repeaters at different sites over a mesh network, point-to-point link, VPN, or public Internet.
Private nodes are reserved node numbers ranging from 1000 – 1999.
A hybrid approach of both public and private nodes can be taken. Repeater 1 at location A,
repeater 2 at location B, and repeater 3 at location C are all at sites with no or poor Internet.
Setup Ubiquity point-to-point links between the repeater site and the Trustee’s house (for
example) with a better bandwidth connection.
AllStar nodes would be setup at the repeater site and use the Point-to-Point as the route to
the Internet. Say you don’t want public nodes to connect directly to the repeater over long-
range WiFi but wanted to link all three repeaters together and have controllable public
access. Nodes at the three repeater sites would be setup the same except as AllStar private
nodes. A fourth node would be setup with a public node number at the Trustee’s house. The
three repeater nodes and any public nodes could be connected or disconnected from the
fourth public node as needed.
A friend of mine in Colorado, Jeff – K0JSC, has his WE0FUN “fun machine” repeater sites
linked in a similar way. The 15 repeaters are private nodes connected over a private
network to a central hub.
Asterisk supports standard protocols for making phone calls over IP, SIP and IAX. Using
these standards makes integration easy with other systems that support similar protocols.
Options range from softphones, hard phones, other Asterisk systems, to PBX systems on
the Internet. A softphone app is an application which runs on a computer or smartphone
providing the ability to make calls. Iaxrpt is the Windows PC softphone client and DVSwitch
Mobile for smartphones. Hard phones are IP connected phones such as Cisco or
Grandstream that support either protocol. A second line on the same Cisco phone used for
Ham Shack Hotline is provisioned to dial into my AllStar nodes. An extension can be added
to an existing Asterisk phone system allowing any handset to dial into AllStar. Last but not
least, a cloud VoIP provider can add forward and reverse autopatch capability to any node!
Loose autopatch ability due to new repeater hardware, an expensive addon board, or it
became cost prohibitive based on use? Though an active Internet connection is required, a
cloud PBX provider, such as voip.ms, adds autopatch functionality for fractions of a penny
per minute (including long distance) with pay-as-you-go pricing. For younger hams,
autopatches connected an amateur station (often repeaters) with the public land-line
telephone system and were popular when cellphones didn’t exist or were expensive.
The first thing about AllStar I found interesting is the ability to interconnect with other ham
radio systems. EchoLink support comes out-of-the-box. IRLP can be added but an existing
node is needed to copy the system key. To obtain a new node number, the purchase of IRLP
hardware is required. Cheapest way is to purchase the preloaded SD card with configured
node on the IRLP Node Order Page for the Raspberry Pi. AllStar has all the essential
capabilities of a repeater controller, IDing every 10 minutes and adjustable time-out
timer. The time-out timer can be disabled with a command – useful when broadcasting
ARNewline, which can be played automatically with a script, or hosting windbag nets. The
scheduler is replaced with Unix Cron. I’ve written custom scrips that announce weather
conditions, PL tone, and number of connections at certain times during the hour. For a net,
my node will check to see if it’s already connected to the far-end node hosting the
net. If it is not connected to that node, it will drop all existing connections then connect to
the remote node.
Dropping all connections seems useful to avoid airing a local net over a large reflector or
being booted from an IRLP reflector for being an irresponsible node operator. Some
repeater owners like to place repeater objects on APRS maps showing repeater location and
frequency. AllStar can inject these objects into the APRS-IS network.
Not unlike the infrastructure flexibility, nearly any sound device recognized by Linux will
work with AllStar. Cheap audio fobs (with a few modifications) to commercially or ham
produced products are all options. The Repeater Builder site offers many options and
products. The connecting device I choose was the DMK URIx. The USB connection converts
data over to a DB-25 connector. Pin assignments are listed on the device itself for easy
access. I wired up a connector using a Motorola connector kit I purchased off Ebay following
instructions I found online from W2YMM. I’ve had a great experience and no problems with
the URIx. However, it’s not cheap now running $85 including shipping. In addition, mailing
lists are indicating a change in chipset is causing performance issues. I would wait awhile
before purchasing this device again.
With Raspberry Pi as an option for running a node, portable nodes are popular for use in a
vehicle or backpack. Open Internet ports, or port forwarding, is not a requirement for
outbound connections. This is especially useful because cell phone companies make it
impossible for open ports due to CGNAT. This was a big problem I talked about with WIRES-
X before Yaesu introduced their portable node software. Incoming connections to a
portable node on a hotspot will not be possible.
There is a fork of the main project called HamVoIP. They were the first to release a
Raspberry Pi image. A Beagle Bone Black image was available but it has been deprecated
and no longer updated to concentrate on the Raspberry Pi image. About the time WB6NIL
passed, the main AllStar project had some internal conflict, upgrades caused lengthy
utages, distributions were becoming dated, and hard to setup. HamVoIP claims to pick-up
that slack, improve on the project including infrastructure and code cleanup. Their assertion
is having better than 70% of the AllStar market running their image. Recent strides have
been made to improve the main AllStar project. I have used both cistributions and feel
HamVoIP does work better, has more features, frequent updates, and better
documentation. Nodes
running HamVoIP still utilize the AllStar infrastructure and are fully compatible with non-
HamVoIP nodes. There is a claim that HamVoIP is in violation of GPL license agreements.
Again, being a former programmer and someone who publishes articles and presentations,
I would be upset if someone was violating my usage terms. However, those making
accusations are also making judgement calls based on lack of response – which doesn’t
mean there is a violation. In addition, a claim can be filed with the Free Software Foundation
or have the copyright owners of Asterisk make a decision. It does not appear either correct
course of action is being pursued. Airing this grievance on social media accomplishes
nothing, as usual. The HamVoIP side isn’t helping their case by not being transparent and
some responses were “feeding the trolls.” A troll is a person online who posts a provocative
message to an online forum with the intent of causing disruption and argument.
You can read the Reddit thread (some language maybe NSFW) and HamVoIP response. I’m
going to keep using HamVoIP until I see a response from someone that has standing in the
matter. AllStar is flexible but definitely a more an administrative (Sysop) system and not
entirely user-friendly. Connecting to other AllStar nodes is pretty straight forward. The DTMF
sequence is *3<node number> to link and *1<node number> to unlink. Integrations with
EchoLink and IRLP can be implemented a couple ways:
directly linked to an AllStar node where the AllStar and EchoLink/IRLP node act as one.
EchoLink/IRLP can be setup on a different node (often private) on the same AllStar setup.
Having separate nodes allows for disabling EchoLink or IRLP connections completely should
those nodes cause problems. Great for control, not great for users. An RF user can link and
unlink EchoLink/IRLP, not to specific nodes. It maybe possible to do with a script but would
add complexity.
Having AllStar and EchoLink/IRLP on the same node allows RF users to link and unlink to
those systems. Remembering the DTMF combinations is not easy, I know. Connecting to
EchoLink nodes is the DTMF sequence *3<node number, padded to 6 digits with 0’s> and
*13<node number, padded 6> to disconnect. IRLP is *38<node number> and *18<node
number> respectively. Example, EchoLink test node #9999 is *3009999 and *31009999 to
disconnect. IRLP test node #9990 is *389990, and *189990. Not exactly straight forward,
easy to remember, or the simple “73” IRLP users are used to for disconnecting. Sysops can
use the Supermon ebpage utility for easier control of a node and can make it read only for
users.
I learned some things about using Motorola equipment. My CDM1250 is the high power (40
watt) UHF model. Radios such as the CDM have a 5% duty-cycle. This means transmitting
only 3 minutes every hour. Don’t forget, these aren’t rag-chew radios – they’re designed for
police and fire which only transmit for short periods of time. Two ways to improve the duty-
cycle is to lower the output power and upgrade to active cooling by moving a lot of air over
the heatsink. Lowering the power on mine is still 25 watts. These improvements allow
the radio to operate normally for a 90-minute net, as long as the fan keeps working. The
antenna connector is a Mini UHF female and very easy to break with an adapter and stiff
coax. A Mini UHF male to UHF SO-239 female pigtail is a requirement. It relieves the stress
on the radio’s connector. Learning about commercial radios has been a valuable experience.
AllStar Link is a very flexible and customizable system that has excellent integration with
other infrastructure. I still have a lot to learn and my next goal is to use AllStar for linking all
digital modes – yes ones like D-STAR, DMR, and Fusion. Stay tuned!
If you would like to make an AllStar contact, it is best to setup a sked with me via Email.
AllStar node map: http://allstarmap.org/allstarmap.html
Technical
Coordinator
Jeff Kopcak, K8JTK
One thing about ham radio, there is no shortage of
linking systems. Most are familiar with analog
linking like EchoLink and IRLP but there were less
popular ones such as WIRES and eQSO. Digital has
many more options because when someone
disagrees with an
implementation, they make another. This allows for
options but leads to fragmentation and
incompatibilities. The AllStar Link project can link
different infrastructure systems together or be a
completely independent system. I learned about
this linking system and accepted
a challenge from one of the Technical Specialists.
Some of your Technical Specialists and I have this
spirited debate about Motorola radios. They are
correct claiming Motorola radios can take a lot of
beating and keep on ticking. Not quite Timex but
close. Commercial radios are designed to endure
extreme conditions. Think police trying to wrangle a
criminal or fire fighters in extreme temperatures of
a working fire. You don’t want to worry about your
primary line of communication being destroyed in
the process. Ham grade gear won’t stand up to that
kind of use and abuse. Older Motorola
gear is very popular with hams as dependable FM
repeaters and for use on 900 MHz. They make great
repeaters because they have excellent adjacent
channel rejection (selectivity) which minimizes
interference from other transmitters.
My counter is most of this gear is not capable of
VFO, a must when working with other agencies and
not familiar with their frequencies. Some models
are better than others getting them to transmit in
the ham bands if the radio’s band split is just above
or below the ham bands. A common practice is to
bring a radio with the 450- 512 MHz split to transmit
in the 440-ham band. Aligning the radio is often
needed because it has drifted off frequency. A
service monitor or RIB (Radio Interface Box) cable
are needed. Everyone should have a service monitor
or scope, few do. Many older radios require a PC
with a serial port and/or DOS application to be
programmed. Serial ports are becoming harder to
find on computing devices. I’ve heard USB to Serial
Port adapters work, for the most part, with the help
of DOSBox. DOSBox is an emulation of DOS that
works on modern operating systems. Primality
designed as a tool to run DOS-based games but it
also works for other DOS applications. To download
a legitimate copy of the Motorola CPS programming
software, the
subscription cost can get ridiculous. A Radio
Reference thread indicated it could range from
under $200 to $400 with an increase last year for
MotoTRBO equipment. As a former programmer,
pirating doesn’t support developers and doesn’t
allow the company to put money back into
developers and adding features. If you’re kind
enough, someone with a
subscription maybe willing to program the radio for
you or find a ham-friendly radio dealer willing to do
the same or sell the software at cost. Pro tip, don’t
ask about pirated software in the RR or in other
forums.
Out of this debate came a challenge from Bob –
K8MD to try out a Motorola radio. I eventually found
a project where I need a radio but the programming
wouldn’t change often. I did a lot of reading and
research on BatLabs and Repeater Builder which are
great resources for repurposing commercial radios
and building repeaters. The used market is where
these radios will be found. Advice from those sites
will be very useful in not getting ripped-off,
especially decoding the radio model number. My
project was to setup an AllStar Link node and it was
a perfect time to try a Motorola CDM1250.
AllStar Link, often called AllStar, is an Amateur Radio
linking system on a Linux computer, running the
opensource PBX telephone switching platform
called Asterisk. An AllStar module called app_rpt
turns Asterisk into a powerful, full featured, Ham
Radio repeater controller, and linking package. It is
theoretically capable of controlling hundreds of
nodes at a time. Jim Dixon - WB6NIL (SK), developed
app_rpt and is considered to be the father of AllStar.
Asterisk is typically used as a SMB (small/medium
business) phone system.
Like other analog Voice over IP systems (VoIP), such
as EchoLink or IRLP, it links radio systems together.
AllStar is flexible enough to link other
infrastructures together as well. The ability to make
connections on any IP network makes AllStar
decentralized, meaning it doesn’t need to rely on
other infrastructure. No central server for someone
to pull the plug resulting in a complete collapse of
the network. The concept of a node in AllStar
terminology is a loose definition but they all run the
same exact software. Node types are generally
defined as:
• Repeater: full duplex node and user functions
accessed by DTMF
• Simplex node: half-duplex node, also with user
functions available
by DTMF
• Remote Base node: a half-duplex, frequency agile
HF, VHF, or
UHF remote base. Will not respond to DTMF on RF.
• Hub node: a common connecting point (similar to
Conference or Reflector) with plenty of Internet
bandwidth to handle many connections at one time,
has no RF connected hardware Nodes can be public,
private, or a combination of both. A public node
would be accessible by any other public node on the
AllStar network and requires Internet access to the
AllStar infrastructure for the phonebook of public
nodes. Private nodes can be limited to select users
or on a completely private network, like a mesh
network, where you don’t want many uses
connecting over limited bandwidth links. These are
great for connecting repeaters at different sites over
a mesh network, point-to-point link, VPN, or public
Internet. Private nodes are reserved node numbers
ranging from 1000 – 1999.
A hybrid approach of both public and private nodes
can be taken. Repeater 1 at location A, repeater 2 at
location B, and repeater 3 at location C are all at
sites with no or poor Internet. Setup Ubiquity point-
to-point links between the repeater site and the
Trustee’s house (for example) with a better
bandwidth connection.
AllStar nodes would be setup at the repeater site
and use the Point-to-Point as the route to the
Internet. Say you don’t want public nodes to connect
directly to the repeater over long-range WiFi but
wanted to link all three repeaters together and have
controllable public access. Nodes at the three
repeater sites would be setup the same except as
AllStar private nodes. A fourth node would be setup
with a public node number at the Trustee’s house.
The three repeater nodes and any public nodes
could be connected or disconnected from the
fourth public node as needed.
A friend of mine in Colorado, Jeff – K0JSC, has his
WE0FUN “fun machine” repeater sites linked in a
similar way. The 15 repeaters are private nodes
connected over a private network to a central hub.
Asterisk supports standard protocols for making
phone calls over IP, SIP and IAX. Using these
standards makes integration easy with other
systems that support similar protocols. Options
range from softphones, hard phones, other Asterisk
systems, to PBX systems on the Internet. A
softphone app is an application which runs on a
computer or smartphone providing the ability to
make calls. Iaxrpt is the Windows PC softphone
client and DVSwitch Mobile for smartphones. Hard
phones are IP connected phones such as Cisco or
Grandstream that support either protocol. A second
line on the same Cisco phone used for Ham Shack
Hotline is provisioned to dial into my AllStar nodes.
An extension can be added to an existing Asterisk
phone system allowing any handset to dial into
AllStar. Last but not least, a cloud VoIP provider can
add forward and reverse autopatch capability to any
node! Loose autopatch ability due to new repeater
hardware, an expensive addon board, or it
became cost prohibitive based on use? Though an
active Internet connection is required, a cloud PBX
provider, such as voip.ms, adds autopatch
functionality for fractions of a penny per minute
(including long distance) with pay-as-you-go pricing.
For younger hams, autopatches connected an
amateur station (often repeaters) with the public
land-line telephone system and were popular when
cellphones didn’t exist or were expensive.
The first thing about AllStar I found interesting is the
ability to interconnect with other ham radio
systems. EchoLink support comes out-of-the-box.
IRLP can be added but an existing node is needed to
copy the system key. To obtain a new node number,
the purchase of IRLP hardware is required. Cheapest
way is to purchase the preloaded SD card with
configured node on the IRLP Node Order Page for
the Raspberry Pi. AllStar has all the essential
capabilities of a repeater controller, IDing every 10
minutes and adjustable time-out
timer. The time-out timer can be disabled with a
command – useful when broadcasting ARNewline,
which can be played automatically with a script, or
hosting windbag nets. The scheduler is replaced
with Unix Cron. I’ve written custom scrips that
announce weather conditions, PL tone, and number
of connections at certain times during the hour. For
a net, my node will check to see if it’s already
connected to the far-end node hosting the
net. If it is not connected to that node, it will drop all
existing connections then connect to the remote
node.
Dropping all connections seems useful to avoid
airing a local net over a large reflector or being
booted from an IRLP reflector for being an
irresponsible node operator. Some repeater owners
like to place repeater objects on APRS maps
showing repeater location and frequency. AllStar
can inject these objects into the APRS-IS network.
Not unlike the infrastructure flexibility, nearly any
sound device recognized by Linux will work with
AllStar. Cheap audio fobs (with a few modifications)
to commercially or ham produced products are all
options. The Repeater Builder site offers many
options and products. The connecting device I
choose was the DMK URIx. The USB connection
converts data over to a DB-25 connector. Pin
assignments are listed on the device itself for easy
access. I wired up a connector using a Motorola
connector kit I purchased off Ebay following
instructions I found online from W2YMM. I’ve had a
great experience and no problems with the URIx.
However, it’s not cheap now running $85 including
shipping. In addition, mailing lists are indicating a
change in chipset is causing performance issues. I
would wait awhile before purchasing this device
again.
With Raspberry Pi as an option for running a node,
portable nodes are popular for use in a vehicle or
backpack. Open Internet ports, or port forwarding,
is not a requirement for outbound connections. This
is especially useful because cell phone companies
make it impossible for open ports due to CGNAT.
This was a big problem I talked about with WIRES-X
before Yaesu introduced their portable node
software. Incoming connections to a portable node
on a hotspot will not be possible.
There is a fork of the main project called HamVoIP.
They were the first to release a Raspberry Pi image.
A Beagle Bone Black image was available but it has
been deprecated and no longer updated to
concentrate on the Raspberry Pi image. About the
time WB6NIL passed, the main AllStar project had
some internal conflict, upgrades caused lengthy
utages, distributions were becoming dated, and
hard to setup. HamVoIP claims to pick-up
that slack, improve on the project including
infrastructure and code cleanup. Their assertion is
having better than 70% of the AllStar market
running their image. Recent strides have been made
to improve the main AllStar project. I have used
both cistributions and feel HamVoIP does work
better, has more features, frequent updates, and
better documentation. Nodes
running HamVoIP still utilize the AllStar
infrastructure and are fully compatible with non-
HamVoIP nodes. There is a claim that HamVoIP is in
violation of GPL license agreements. Again, being a
former programmer and someone who publishes
articles and presentations, I would be upset if
someone was violating my usage terms. However,
those making
accusations are also making judgement calls based
on lack of response – which doesn’t mean there is a
violation. In addition, a claim can be filed with the
Free Software Foundation or have the copyright
owners of Asterisk make a decision. It does not
appear either correct course of action is being
pursued. Airing this grievance on social media
accomplishes nothing, as usual. The HamVoIP side
isn’t helping their case by not being transparent and
some responses were “feeding the trolls.” A troll is a
person online who posts a provocative message to
an online forum with the intent of causing
disruption and argument.
You can read the Reddit thread (some language
maybe NSFW) and HamVoIP response. I’m going to
keep using HamVoIP until I see a response from
someone that has standing in the matter. AllStar is
flexible but definitely a more an administrative
(Sysop) system and not entirely user-friendly.
Connecting to other AllStar nodes is pretty straight
forward. The DTMF sequence is *3<node number>
to link and *1<node number> to unlink. Integrations
with EchoLink and IRLP can be implemented a
couple ways:
directly linked to an AllStar node where the AllStar
and EchoLink/IRLP node act as one. EchoLink/IRLP
can be setup on a different node (often private) on
the same AllStar setup. Having separate nodes
allows for disabling EchoLink or IRLP connections
completely should those nodes cause problems.
Great for control, not great for users. An RF user can
link and unlink EchoLink/IRLP, not to specific nodes.
It maybe possible to do with a script but would add
complexity.
Having AllStar and EchoLink/IRLP on the same node
allows RF users to link and unlink to those systems.
Remembering the DTMF combinations is not easy, I
know. Connecting to EchoLink nodes is the DTMF
sequence *3<node number, padded to 6 digits with
0’s> and *13<node number, padded 6> to
disconnect. IRLP is *38<node number> and
*18<node number> respectively. Example, EchoLink
test node #9999 is *3009999 and *31009999 to
disconnect. IRLP test node #9990 is *389990, and
*189990. Not exactly straight forward,
easy to remember, or the simple “73” IRLP users are
used to for disconnecting. Sysops can use the
Supermon ebpage utility for easier control of a node
and can make it read only for users.
I learned some things about using Motorola
equipment. My CDM1250 is the high power (40
watt) UHF model. Radios such as the CDM have a
5% duty-cycle. This means transmitting only 3
minutes every hour. Don’t forget, these aren’t rag-
chew radios – they’re designed for police and fire
which only transmit for short periods of time. Two
ways to improve the duty-cycle is to lower the
output power and upgrade to active cooling by
moving a lot of air over the heatsink. Lowering the
power on mine is still 25 watts. These improvements
allow
the radio to operate normally for a 90-minute net,
as long as the fan keeps working. The antenna
connector is a Mini UHF female and very easy to
break with an adapter and stiff coax. A Mini UHF
male to UHF SO-239 female pigtail is a requirement.
It relieves the stress on the radio’s connector.
Learning about commercial radios has been a
valuable experience. AllStar Link is a very flexible
and customizable system that has excellent
integration with other infrastructure. I still have a lot
to learn and my next goal is to use AllStar for linking
all digital modes – yes ones like D-STAR, DMR, and
Fusion. Stay tuned!
If you would like to make an AllStar contact, it is best
to setup a sked with me via Email.
AllStar node map:
http://allstarmap.org/allstarmap.html