GB7CIP Amateur Radio International Gateway.

Mail forwarding over AX25, NetRom, IP and SMTP  via HF PACTOR over
Amateur Radio Short Wave bands, VHF, UHF, amprnet wireless and internet links.

G4APL MaintainedUK AX25 BBS Listings 
G4APL MaintainedGB7CIP Forwarding (pdf)

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QRZ callsign lookup:

Data Over Amateur Radio

Since the mid 1970's. Licensed Radio Amateur's have been experimenting and learning about using Real Time Data Over The Amateur Radio Bands. Well before the Internet as you know it is today.

The sort of things that can be achieved today, is using something Similar to Facebook messanger, Internet Relay Chat by using the XCHAT Real Time Chat by connecting to an Amateur Radio Real Time Convers Servers. In addition to the Email and the old InterNetNews services being provided over our AMateur Packet Radio NETwork.

Amateur Radio is an Excellent Hobby to get involved in. Other Radio Amateur's are happy to welcome you and give encouragment as you make friends.

If you are new to Amateur Radio, you can get brief overview of what it is about by watching the
short RSGB video Amateur Radio in the 21st Century by clicking on this link.

RSGB 20 Things you can do with Amateur Radio pdf document

Amateur Radio overview. Another Interesting article

Amateur Radio WorldWideConvers Networks
Talking to like minded persons. These real time data and Convers servers have been running here in one form
or another since the late 1980's on a network known as the amprnet AMateur Packet Radio NETwork.

What is the AMPRNet? I hear you cry!

This is the original IP AMPRNET MESH Network currently consisting of 600+ connected IP
Amateur Radio network gateways.

For additional AMPRNET information select the TCPIP tab on this website.

We have in the late 1980 earley '90's ran network games over the IP radio networks.
Some that have been successful Network Games, i.e. Scrabble, Battleships, Connect Four, Monopole

This is in addition to Access the Real Time DX Station Spotting, One to One Contacts. Email and Newsgroup Services.
To achieve all this, requires some understanding howto Interface the Amateur Radio to a PC Sound Card or Terminal Node Controller
TNC), Data Communication Controller and locate suitable software.

Connect to your local Amateur Radio Network Server providing Real Time Data over Radio.

This is the enjoyment of Amateur Radio
in finding out how things work, carry out tests, solve the challenges (problems) encountered and how all this underpins all the communication technolegy that you use every minute of the day.

Assisted by
Paul G4APL and other Radio Amateur's that are very keen to help new comers (or Old Timers) to this side of the hobby.

You would hopefully get
great satisfaction that you got one part to work, before moving on to the next and whilst increasing your knowledge.

can also be achieved using Internet, Wi-Fi  LAN, HF, VHF, UHF frequencies.

Your learning starts after you have correctly configured your
Amateur Radio transceiver to your PC/Laptop/Raspberry Pi via a Hardware Data Controller, TNC or a Soundcard Interface.

Then getting to grips and understand
AX25, TCPIP and Networking over the Radio, mobile phone, WiFi and Internet.

More information can be found under TCPIP Notes.

Operating HF AX25 APRS  Robust 600baud. G4APL is active part time using his SCS PTCIIex and TS2000e on
this mode on 10.147.30MHz.The SCS PTCIIex has R600bd included as one of the packet modes (Baud R600).

To quote from their website:-
"The goal of Robust-Packet-Network to make Robust Packet Radio
more popular within the HF-APRS community and to strengthen the network".

For frequencies and background information please refer to

Kenwood Transceivers
How to Configure your TS2000e to access your Local Packet Radio Node
Paul G4APL enjoys using his TS2000e sub-receiver on 2mtere 1200baud and 70cm 9600baud Radio data speed to access the local packet radio node. Accessing the world wide Amateur Radio Packet Network. 

At the same time using the Main Receiver on HF SSB, PACTOR, 300baud, 600baud Packet Radio using a suitable data controller. 

Have you got a Kenwood TS2000e that you are not using to the FULL?? Why not join us!

Describes How To Configure Kenwood TS2000e for AX25 Packet Radio
How To Configure the Kenwood THD7e THD72e TM-D700 for AX25 Packet Radio  and THD74e
How To Configure the Kenwood TMD710 for AX25 Packet Radio by David Ranch KI6ZHD
using the built in TNC (Terminal Node Controller) TASCO RADIO MODEM using Windows XP, Windows 7 Pro, Windows 8.1,
Windows 10, UBUNTU Linux and the PaKet 6.2 Packet Program.
Of course you could  use your favourite Packet AX25 program application.
Paul G4APL has also run DOS JNOS (IP over AX25) using the built in TASCO Radio Modem
at 1200baud and 9600baud RF radio speeds on 70cms. 1200baud on 2metres.
more details can be found on the tcpip_notes web page section 'k'.
Remember to set MAXFRAME 1 and PACLEN 256 due to limited internal buffers in these radios,

Raspberry Pi
A lot of Radio Amateur's are now using Raspberry Pi's with legacy TNC e.g. {PacCom Tiny2, BSX2)
or using a soundcard software drive inplace of the hardware TNC's.
Paul G4APL has set up an experimental Linux Node APLRPI (APple and RaspberryPIe)
using his Raspberry PI B 256MB Ram (August 2012) base on information from the following web sites.

In early 2016 this now using a Raspberry Pi 3b and the RPI1b is now running as an Apache2 web server.

Note: This setup was used as his temporary Node G4APL-2 in November 2014 on 144.9375MHz.
Connected via a USB<>Serial cable to a PacCom TNC200(with JKISS prom) and Kenwood TR751e.
Linked to GB7CIP-5 main Linux server via an Ethernet amprnet tunnel to access the main AX25/AMPR network gateway.

Note: re Serial connection.  As another Sysop had issues and confusion.
Raspberry-Pi | |USB<>SERIAL:D9Mail | Back-Back<D9>Adaptor| D9Mail-Straight-Through-cable-D9Feamale | Paccom-Tiny2 TNC

Paul also replaced the standard TNC2 Eprom with a dedicated JKISS prom configured with his callsign CWID
Save him having to switch the standard TNC software into KISS mode first.

Amateur Radio using a Rasberry Pi
Charlie K4GBB Raspberry related Web site

Bernard F6BVP Raspberry Pi installation howto related Web site updated 20 February 2016

LinFBB F6FBB BBS LinBBS project

G4APL uses the latest unofficial supported source on his installations using Charlie's K4GBB scripts that download, compiles and installs the above then manually edits the configutations files.

Before running this script. Make sure that 'automate' is installed by running
sudo apt-get install automate

Using his Linux experience on his main gb7cip system and with the Raspberry PI detailed above.

Paul G4APL has been able to assist other UK Radio Amateurs, who request his help (guidance) and assistance with their Raspberry Pi's (or Desktop PC) Linux installation of all the required AX25 software source code, configuring and networking as part of the Regenerating Radio IP network activity in the London Home Counties area.

LinPac Packet Rado Terminal
G4APL LinPac Notes experience using LinPac by David Ranch KI6ZHD, OK2JBG and their support team.

Linux Soundcard TNC Emulator
Dire Wolf is a software "soundcard" modem/TNC and APRS encoder/decoder.
for more information refer to the website.
G4APL has no first hand experience of this though highly regarded by other Linux users accessing the Amateur Packet Radio network using Radios and usb soundcard audio interfaces suitably adapted..

Note:  RE ISP Supplied Domestic Routers.
Just a few comments.

'We' have found most of these routers do not allow the 'Forwarding of Protocol 4 (ipencap)
i.e. No RAW setting that you are able to enter 4

They only allow Protocol 6(TCP) and 17(UDP)  (TCP/UDP) in their supplied routers/firewall configurations.
Which prevents setting up the amprnet IPIP tunnels.

Alternatives are peering with a partner using a UDP Tunnel which is safer than
Pointing all 'your'  Live Internet data to a device acting as a DMZ  (Demilitarized Zone) on your Home Network LAN.

Where you need some expertise in installing and configuring firewalls to protect your internal network (LAN, WiFi), amprnet tunnel internet links and radio ip links. 
From the continous probes to all the common port services by the 'bandits and bots'.
That are open on your LAN and system.

URONODE released by Brian N1URO
This is a front-end interface.  uronode and axmail makes calls to back-end supporting
separate back end processes, services that you need to install and configure, compile the
AX25libs, tools and apps first.
Then use this application to give a friendly front-end user access.

March 2017  Brian N1URO has kindly created two installation scripts
to do the above for either systemd(jessie) or sysv(Wheezy) linux based systems

Both packages are available from ftp server at
in directory   /pub/hamradio/packet/ and you will see the instal scripts for systemd and sysv..
These scrpts should make your life easier to get-up and running your linux packet system.

N1URO distributions for Raspberry Pie and standard Linux.
Fairly straight forward to setup, by following the README files.
On a test system G4APL was only interested in the AX25 NETROM IP, AXMAIL(amprnet) and Serial
side of this system at this time.
Uronode current version 2.9 release  at 31.5.2018

Once you have downloaded the required Distribution and
extracted the files. That's another skill.

Proceedure G4APL uses to decode the URONODE tgz image on a Windows PC
Note the original linux file is first run through tar and then bzip. so we need to decode this
file twice to produced the image file to be input to Win32DiskImager.
You will also need a copy of 7-Zip 16.02 open source program.

After downloading the image file 2014-12-05-URONode-wheezy.tz2
image file 2016-06-12 uronode-jessie-RPI3.tar.gz
using a Microsoft Windows based machine.
This file will fit on an SDmicro 16GB memory card.
includes create and README text files. 

Extracting the image
Using 7-Zip with the downloaded file detailed above as input. Will produce the
extracted file
2014-12-05-URONODE-wheezy size 3872260KB

Then run 7-Zip again on the previous extracted file above.

You will see and RaspberryPi directory
extract the README and the
2014-12-05-URONode-wheezy.img files


load 7-Zip
(pass 1) input file uronode-jessie-RPI3.tar.gz
(pass 2) input file/directory uronode-jessie-RPI3.tar

You will end up with directory rpi3-image in which you will find three files
create and README and the image file uronode-jessie-RPI3.img

This image is based on a SanDisk 16GB Micro SD card provided with the RPI3-B
sold at the 2016 Dayton Hamfest. Run the create script (if fhe sd card is on a Linux machine)
then edit the files in /etc/ax25, /etc/postfix, and also /usr/local/bin/ax25. Look for MYCALL
or mycall (upper/lower case) and remove ALL <>'s, and replace MYCALL or
CALLSIGN as it appears (upper/lower case) with your callsign.

Though Paul stardarised using 16GB SDMicro class 10 cards, allowing more file system space for logs and
other additonal features that may be required.

Insert your SDMicro memory card in to your PC/Laptop card reader, or USB Stick adaptor.

Using Win32DskImager which should detect the drive containg the memory card.
Changed Save as file type to *.img
Select file above, and SAVE
Select Write

Confirm overwrite YES

Safely release the SDcard from the PC.
and removed from cardreader/writer

SD card into RPI
Connect Keyboard and HDLC Screen(in my case a TV)
(I modify my /boot/config.txt to use a 19inch LCD screen via
an HDLC<>VGA adaptor - one Paul use to log on to the system,
when Paul is not accessing it remotely using putty)

Extract from README file
You will need your login info. It is:
Username: pi
Password: uronode  (Important, change this when you have logged in)

When you boot this image once created, follow the instructions on the screen
to get your node running.

You should be able to get it (basically set-up) up within a couple of hours  or so (10 minutes) time.
The information you'll need can be found in
/usr/local/bin/README as well.

Raspberry Pi build using jessi-lite experiment

Warning still valid!! 17-7-2016<=>1.6.2018 it has been reported that the AX25 Stack processes are broken. Understand there is no fix for this on the horizon!! Other than rebooting your system.
Blah Blah [snip] "raspberry pi
But, also note that *any other Linux* kernel above 4.1 has more holes in it for the ax25 stack than does a golf
course. (Linux system locks kernel error up requiring a reboot)
For now you may wish to consider downgrading to a 3.x" (also applies to debian, ubuntu)

Paul G4APL is using 4.1.17 and 4.1.19 with success
Raspberry Pi Jessi-lite 4.1 2016-03-18-download site
DO NOT DO apt-get dis-upgrade after installation, otherwise you will find you are running 4.4 kernel broken AX25 stack.

1) Raspverry Pi 1GB Version 2 Model B
2) jessie-lite kernel 4.1.19-v7 Raspberry kernel Pi image
2a) amended /boot/config.txt to use 'VGA' (15 pin) 19 inch LCD screen adapter
re Newer Black HDMI Inout to VGA Adapter Converter for PC Laptop, Raspberry PI

Add the following code at the end of /boot/config.txt
if you want to use the above adaptor with a VGA(15 pin) interface LCD Screen
Boot settings for Flatron VGA Monitor
# 1024 * 768
# note hdmi_mode=16 is the display resolution at 1024 x 768

3) install the unoffical ax25 source code
using Charlie's K4GBB scrpt
referred on his web site detailed earlier on this page.

4) installed brian's N1URO uronode-2.7 Source

5) Now just need to configure the configuration files
as well as use the 'new' N1URO's systemD config files for the
services that Brian created. Saved a lot of 'learning pain'.

5a) Paul's G4APL AX25 configurations files

Configured and working now, proved that it can be done
G4APL-7:APLPIE Node when online.

Have also rebuilt G4APL-5:APLRPI node
ax25 udp vpn via WiFi/3G broadband gateway
Paul 9.8.2016 23:00

For Ubuntu AX25 installation
Use Ubuntu Trusty 14.04.1 LTS image Kernel  3.13.0.#
Ubuntu 14.04.2 LTS (Trusty Tahr) link to 14.04.1 LTS Images g4apl is using 32bit as requires realiability.

Ubuntu 14.4.2 LTS image installs the new Hardware enablement Stack (!!!!!!)
and  Ubuntu 14.04.5 LTS image installs Kernel 4.4 from the 16.04LTS release!! 

Follow the detail in this link up to and not including RMS.
RMS Winlink is not authorised by the UK Authorities for Radio Amateur use. As this is not a
dedicated Radio Amateur to Radio Amateur service. (G4APL was advise of this in November 2014)

Caterham Broadband-Hamnet HSMM MESH 13cm 2.4GHZ WiFi HamNet (Amateur Radio) Project

Since 2000 Paul G4APL has been experimenting on and off with
his WiFi Hubs in WDS bridging configuration. One of which is a remote 'router'.

Paul has replaced this equipment and and started experimenting in using the Amateur Radio  Broadband-HamNet version 1 (High Speed Multimedia) HSMM MESH software with suitable WiFi Routers and operate them in the 13cm 2.412GHz  Amateur Radio Band.(WiFi Channel1).

It is proposed (now operational) to use the Broadband-Hamnet Version1 HSMM MESH software on the routers now known as MESH nodes as a 'network cloud' to connect back to the 44Net Amateur Radio Caterham Hub (
East Surrey amprnet network

The Nodes will show up on the Mesh network as GB7CIP-2441A and GB7CIP-2441B.

A third and forth node connected to a laptop, will be set-up for experimenting as a remote user with beams and plate aerials.
Node ID G4APL-244A

The Firewalls at gb7cip are configured only to route on Source and Destination address
in the AMateurPacketNETwork (amprnet). To ensure only Radio Amateurs are communicating over the Infrastructure.

i.e. from Mesh Address to Address 44.131.###.### 44.131.###.### at the MESH Node firewalled gateway.

This will allow connections to any Radio Amateur active on the amprnet via the 'tunnels' at GB7CIP gateway.

A Radio Amateur that has a suitable router and a laptop/PC.
Installed the Broadband-Hamnet Version1 HSMM MESH software on the WiFI Router.
(Currently using the default software configuration)

Confirmed that his/her WiFI Broadband-Hamnet HSMM MESH node can see other Nodes in the
Caterham On The Hill area can see GB7CIP-244B Node (when) which is now operational.

You may need to experiment with Vertical Polarisation WiFi Beams or panel hi-gain aerials. As the aerials
used are vertical polarisation.

Anyone in the Caterham Area, Old Coulsdon area (high up) that are Interested in experimenting please make contact.
The more Amateur Radio Mesh Nodes the better for the experiments.

Paul expects to start configuring, testing (experimenting) from October 2013 to see if this set-up
works as proposed.

Broadband-Hamnet background information can be found on the following web site

Also another interesting project using the Raspberry Pi as a Broadband-HamNet Node
Info about the HSMM-Pi project
can be found on the following website
HSMM-Pi Blog
Paul G4APL SysOP GB7CIP 20.9.2013

Hello All

Follow up to my previous update.
I have progressed faster that I had expected, since I wrote the original
message a few days ago.

The two Cisco WRT54GL routers have been 'flashed' with the Broadband-Hamnet
Version 1 software. Configured as mesh nodes. for more information.

Both running as an experimental test setup.
Worked out the required networking via my external firewalls and the gb7cip servers.

Laptop connected the 'local hamnet gateway' LAN interface.

Proved that this laptop can connect out to the amprnet
(AmateurRadioPacketNetwork) NET44 IP Network.

Connected and accessed GB7CIP IRC Convers Server, AX25 Network Node, BBS and Web Server running Also proved that I can connect to other 44Net amprnet Hosts.

So far so good. Amateur Radio via 54Mbit WiFi Links... Now just need more
locals to join in and add mesh nodes.

Next test is to try it from a third mesh node (need to get another router and
configure it first) and and carry the same tests as a remote Mesh User coming via an intermediate mesh node on the external aerial..

Update 5.10.2013
Couple of Gotha's

On the Laptop/PC connected to the Mesh Lan Port
Ensure that the WiFi is turned off, as that had a default gateway pointing the wrong
way and overriding the link to the remote Mesh Nodes.

Also check other static LAN network setting for default gateway pointing in the wrong direction.
On a Windows machine the command route print will display the current routing table.

If you have connected to the Caterham Amateur Radio Broadband Hamnet mesh
you could try a test and ping to see if the Gateway is currently active and get
the following response>

e.g. ping

Pinging [] with 32 bytes of data:

Reply from bytes=32 time<1ms TTL=255
Reply from bytes=32 time<1ms TTL=255
Reply from bytes=32 time<1ms TTL=255
Reply from bytes=32 time<1ms TTL=255

Gateway across the mesh to the Web server using your favourite web browser web server

Use telnet program like TTYLink, Putty  to telnet node port 23 and BBS on port 6300.
Xchat to port 6667 (IRC interface) chat server

As well as other amprnet address via the amprnet gateway are reachable
during this experiment.
Access to other Internet addresses are locked down by a dedicated firewall.

The  experiment continues when there is some spare time to play
Hope the above is of interest

Paul G4APL SysOP GB7CIP 7.10.2013

Hi Again another update
Have been testing over recent months the radio paths with another 'mobile Mesh Node) to see how far the 2.4GHz  goes over the local area Not that far.
Though we are in the progress of adding hi-gain aerials to our systems, so that we can experiment further and extend the range.

Oh yes, forgot to mention, if you do connect, there is a WWW web server active (when it is switched on) within the Caterham Hamnet Mesh.
Which will be useful to you for testing connection the connection to our systems

Paul G4APL SysOP
 GB7CIP 23.3.2014

Broadband-Hamnet version 3
WiFi 2.4GHz

Updated the three WRT54GL routers to version 3.1.0
As I had a spare hour to play with this.
Paul G4APL SysOP 10.6.2015

Installed and removed ngircd IRC Chat server package on the Mesh node.
Found it incompatible with the main WorldWideConverse Servers run at  Also found this
incompatible with colrconv linux covers client.

Installed Hamchat package. A simple standalone chat server visible from the GB7CIP Broadband Hamnet Mesh nodes.
Paul G4APL
17.7.2016 16:50

Raspberry PI Mesh Node HSMM-Pi project Version 0.4.0
G4APL-244B built and running on 256MB September 2012 B version
and using and EDIMAX EW-7811Un WiFi nano USB Adapter. As an experiment.

As Paul did not have a USB WiFi adaptor for use with external aerial.
At least it proved the software installation.

Following Scott Kidder's instructions detailed at the following website which
was straight forward to understand, after having experience with setting up the WRT54GL based BroadbandHamnet Mesh Nodes using Network SSID BroadbandHamnet-20-v3

This mesh node lists the IP addresses of the three WRT54GL mesh node (not the hostnames) and connects to them successfully.SSID set to BroadbandHamnet-20-v3.
Though unable to connect back to the RaspberryPI  Mesh node.and not picking ip the Service advertised from GB7CIP-244A at the present time.

The WRT54GL Mesh nodes are not showing this G4APL-244B raspberryPi node in their Mesh Tables
hence does not know how to connect back.
So appears to be an incompatibility or misconfiguration issue or the USB WiFi adaptor chipset may not not compatible running in Adhoc mode.

Need to get this resolved, before experimenting with vtun.
Paul G4APL SysOP 13.6.2015 23:45

Now connected up an ALFA AWUS036NH USB WiFi adaptor to the Raspberry Pi HSMM-Pi
system now working as required. 
Just connected up this WiFi adaptor, no software changes at this time.

Updated the RaspberryPi  software using the RaspberryPi original Model B Sept2012
and HSMM-Pi version 0.4.0 now running on a RaspberryPi Version 2 Model B.
The plan is to run this off a battery to enable portable operation.

The original RaspberryPI 256MB Ram Model B (Sept 2012) running Apache2 web server has now replaced
the Vista Laptop. T
hat was running the websever for access via the Broadband Hamnet giving detail of access
to amprnet server.

The second RaspberryPi Version 2 Model B will be use for experimenting with Packet Radio configuration SDRam cards that have also had their operating systems updated to 'Jessie' as part of upgrading to the Version 2 B boards.
Paul G4APL SysOP 8.1.2016 21:20

Additional Information
Other Radio Amateurs are runing their own Voice over IP, Video Servers and  Communications Networks..
As well as using this type of system at their field day contests sites or other portable activities, Emergency Communications.

Raspberry Pi SDR (Software Defined Receiver) Server
Next background project with a Raspberry Pi Version 3 Model B
Jessie Full image installation..

Is to build a SDR (Software Defined Receiver) server.using one of G4APL'a DVB DAB FM dongal, currently used with a HDSDR or SDRSharp clients. With the addition Ham It Up Converter 1.3 hardware PCB.

Now have the SDR server running on the Raspberry Pi (RPi) using the DVB T RTL2838UHIDIR DVB-T+DAB+FM Dongle (purchased off eBay previously) and remote access to the RPi server from a Window XPpro Laptop or Windows 7 Pro Laptop running SDRSharp listening to Radio2.

G4APL followed ZR6AIC Anton's excelllent notes as a basis in configuring
this remote SDR software and now running on his Raspberry Pi Version 3 Model B with Jessie-full
Saved him reinventing the 'wheel'. Video was very helpfull.

Remote access over Internet working with a Client connection to the Raspberry Pi SDR Server. 
Use the Raspberry Pi V3 Model B built in WiFi interface to a WiFi Connected Laptop via a WiFi Router.
Found the audio breaking up.  Due to the lack of ADSL uplink bandwidth.

Aerial was a 3 element beam or a vertical aerial. So proving that the Dongal and UP Converter works. (Before being connected to the Raspberry Pi V3 for further testing).

Further update
Now have the the Ham It Up Converter 1.3 working with the 'Dongal' providing the Intermediate Frequency (IF) ( Approx 125MHz). With SDRSharp and HDSDR SDR Windoes software clients, tuning around the HF 7MHz and 14MMHz and SW broadcast bands and WWV frequency standard transmissions on 5.000MHz or 10.000MHz AM on a Windows 7pro and WinXP laptops.

Have learnt more about SDRSharp client and configured for remote accees to the Raspberry PI SDR server (single session).

Now set up with a 6metre vertical dipole when only using the Dongle in bypassmode, or a 5 band HF trapped
vertical when in upconverter mode.

Listened on 198kHz (long wave) Medium and Short Wave broadcast bands, Amateur Radio frequency bands 160,80,40,15,10metre and any other frequencies.

Modes NBFM, WFM, DSB,LSB,USB,AM,CW (not used Raw)

The experiment and learning continues.

Laptop/PC plus Soundcard Interface to Radio Amateur HF/VHF/Radio Transceiver Packet PACTOR mode 1

If you have not got hold of an old Hardware Terminal Node Controller (TNC)
(There must be hundreds on shelvs not being used today that were used in the 1980,1990's)

You could try using your PC/Laptop Soundcard plus a soundcard/Radio Interface
G8MNY's home made Soundcard interface is an example.

MULTIPSK (Free software)
Includes Pactor mode P1 that can be used to connect to GB7CIP HF PACTOR  and Experimental HF PACKET interfaces.
As well as the standard Packet Radio  mode 1200baud for use GB7CIP VHF, UHF 1200bd frequencies.

There are plenty of other PC soundcard solutions out there on the Internet that you could use to access GB7CIP/MB7NCR supported services.

Paul G4APL SysOP
Reviewed 27.9.2018