Finnish Made PMR, Trunking and Cellular (NMT) Phone

Amateur Radio Conversion Pages

Nokia, Mobira, Televa, Benefon etc.

'The Home of Moppe'

We Hate Frames!

Tämä sivu suomeksi - Esta pagina en español - Cette page en français - Questa pagina in italiano

Last updated Monday, 7th July, 2002

These pages are dedicated to converting old two-way radio telephones (PMR) and cellular phones for radio amateur use. We specialise in equipment made in Finland like Nokia, Mobira and Benefon, but you'll also find lots of links to other brands.

We would like to give our sincere thanks to everybody who have donated material to this page and our ftp server. Our special thanks go to Aatos Poutiainen, OH8JEP, the creator of the French, Italian and Spanish pages.

You won't find modifications for commecially made amateur radio equipment or scanners here. Our favourite source for them is

Fast buttons

Benefon Forte/Class NMT450/900 - Mobira HC16/HC17 - Mobira HC17/HD17 - Mobira R20/R21 (Philips PRM80) - Salora SRP24 - Mobira MC25TVL/PTL - Mobira MC25TAKSI - Salora SRP25/Mobira MC25/Nokia SV1381 ARP - Mobira RB25/RC25/RD25 PMR - Nokia SV1300 S/C-2M - HB30/HC30 (AEG Teleport 9) - Nokia HC40/HD40 (Kyodo KG109T, Key Radio KP80T/KP150T/KP450T) - Nokia HC45/HD45 (later KG109T) - Nokia RC40/RD40 - Nokia RB58/RC58/RD58 and Computec RB580/RB660 - Nokia R58 as a repeater - Mobira Cityman 450 (CD60) - Mobira Cityman 900 (CE61) - Mobira Talkman (MD50/MD59/ME59) - Mobira Talkman 510 (MD94) - Mobira Talkman 520 (TMF-1) and 620 (TMN-1) - Nokia BB58/BC58/BD58 base stations - Nokia BSR80/BSR150/BSR450 base stations (Kyodo KG110) - Other brands - AP700/AP2000 - AP4111/AP4112 - Ericsson - Storno/Motorola - Motorola and GE/Ericsson (USA) - Philips/Simoco - Tools and Additional Information - Links to other conversion sites - FTP server -


7 July 2002

A new 2 m ham firmware available for AEG Teleport 9 (Mobira HC30) on the Dutch "Jan Corver" radio amateur museum pages.

5 July 2002

We are far behind the schedule in bringing the English pages up to date with the Finnish Pages.

There are two free firmware versions available for the Philips FM1000 series on PA1MT's FM1000 Pages.

22 October 2001

Only some minor overhaul. The webmaster is still quite busy although the excessive travelling earlier this year has finally ended.

We are still working on restructuring the page after the Finnish conversion pages to make browsing easier and the download times shorter. Please be patient.

18 June 2001

Willempro EPROM programmer user interface for Window$ 9x/2k/NT.

4 June 2001

OH3HSU has taken some pictures of the Mobira HC17 handportable.

Some pictures added on the page.

The AP4111/4112 directories are updated from the OH8JEP pages.

OH8JEP has written a note for MD59 squelch adjustment.

Some MD59 pictures.

30 May 2001

OH2AUS has written a short modification note in Finnish for the Televa 800 base station. Also pictures of the Televa 800-based OH2RAA 2 m repeater and the duplexers.

OH8JEP has been busy updating the Spanish pages. The French and Italian pages fill follow suite later.

21 May 2001

The primary site for the most recent AP4111/4112 software updates and modification notes is now the OH8JEP AP4111/4112 pages.

13 May 2001

AP4111 conversion instructions: a new version of the VCO modification instructions (OH6MF), antenna switch parts placement (OH6MF), pinout of the RX front end FET (OH8JEP) and connecting 9600 bps packet modem (OH8JEP).

8 May 2001

Pictures of what is inside the AP4111 NMT450courtesy of OH9MBS.

Modifications for MD94 TX VCO by OH6MF.

AP4111 ham firmware user interface by OH6MF.

MD94 processor board modifications by OH6MF.

Connecting the Danish YAM modem to a MD59 by OH8JEP.

The happenings of the last year were finally cleaned to their own page. We are thinking about restructuring the page to make browsing easier and the download times shorter.

22 April 2001

A new ham firmware and conversion notes for the AP/Philips 4111 NMT450 transportable phone.

19 March 2001

Pictures of Nokia MD94 transportable NMT450 phone (Talkman 510).

We have created a new directory for antenna switch boards. New pictures of two 70 cm antenna switch designs for Nokia RD58/MD59 by OH3UW.

12 March 2001

The modification pages in French, Italian and Spanish by OH8JEP have found a new home at

Version 0.01 of the ham firmware for the Mobira Talkman 510 NMT450 (MD94) has been put on the server.

8 March 2001

First version 0.00 of the ham firmware for the Mobira Talkman 510 NMT450 (MD94) has been put on the server.

More pictures of Key Radio KP80T.

4 March 2001

A new ham firmware for the Key Radio KP80T portable 4 m trunking set.

News on this page in 2000

News on this page in 1998 and 1999

During the history of this page we have received a lot of enquiries for the English modification guides for various equipment. In general the answer is: please read these pages carefully and often, all information will appear here as soon as we get it. This really means it. If you can't find the radio on this page, on our Finnish Page, in our FTP directory, with our Search Engine, or on the pages we link to, we probably cannot help you. Please remember that most firmware and guides are and will be for phones that were manufactured for the NMT cellular networks in the Nordic countries (Denmark, Finland, Iceland, Norway and Sweden). The modification guides may help you to modify equipment made by the same manufacturer for your local networks, but the firmware will not always work in other versions.

Please do not mail the webmaster or general mailing lists of the club for conversion info. It only irritates people whose main interests are in completely other aspects of our hobby.

When you ask more information about specific equipment on the list, please follow these guidelines:

This will help people on the list in processing your enquiry in a comparatively short time.

Please do not bother our mailing lists with requests about phones currently in production or their spare parts. We are simply not interested.

If you are interested in software design, most of the source code is available on the server.

The history of these pages goes back to the autumn of 1996 when one of our members, OH3BK, received an offer from a friend of his to buy a batch of a dozen or so Mobira MC25PTL's that he had found with the Benefon Forte he needed himself. Well, another one of the members, OH3NYB, had a partnership in a company that used to manufacture an interface box for the radios so he still had a service manual. The beast was powered by the ubiquitous 1802, of which OH3NYB had more than enough experience, but for some reason he was not very keen to start writing firmware for it. Enter Juha, OH5NXO, another eternal university student from Lappeenranta who was locally well known of writing multi-user multiple tasking operating systems on the table napkins during the coffee break combined with some perverted addiction for embedded systems. Well, the email traffic for the developers and test users made it necessary to start a mailing list on the club's linux server The firmware versions and modification notes were put on the ftp server, and soon there was a WWW page where you could find all information easily. Some interest for our firmware and notes developed soon outside Finland, too, so we added this page. We hope you'll find it interesting and useful. The Italian and Spanish pages have been made by OH8JEP and the French and German pages are in the planning stage.

Unfortunately, the English page is updated rather intermittently due to various other commitments of the websmiths. Always have a look for the latest firmware releases on our ftp server, too. We have prepared a short tutorial to the firmware versions and Finnish documents. Some directories do have "00Index" files now, we'll add more when time permits.

The ham firmware and conversion documents on our server are centered around the Finnish made PMR and cellular radios like Nokia, Mobira and Benefon. We try to provide links to our friends abroad who are into converting their domestic brands.

On these pages you see what once was a completely new approach to modifying mobile phones for radio amateur use. Traditionally surplus equipment with processor control has been frowned upon in the amateur community. The beasts "had that darn processor that nobody knows a thing about" or you could buy a new all-whistles-and-bells multiband radio for the money you'd have to spend for the RSS software needed to cajole the thing on amateur frequencies. After all, you'd have a radio with an awkward user interface designed for PMR use. Well, we used some lateral thinking often recommended by Michael, OH2AUE, and went around the dark corner to look what we could find. We believe that we were the first hams in the world to write totally new firmware to the original processor board of PMR/cellular radios, just starting from an example of the radio, a copy of the service manual and a load of IC data sheets. Later a similar approach to the problem has been chosen by e.g. a group of hams in the Czech Republic and also groups in Holland and France. Come on, it's not so hard. The processors are the same everybody used in embedded system design at the time the phones were designed, and the designs are usually very straightforward. Remember, there already have been the RF guys and the audio/HW guys with years of work towards a design for a good radio. The only thing that was left over for you is to design the firmware for simple user interface and radio control, and maybe a filter and TX/RX switch board to replace the duplex filter with.

Most of the firmware has been written by Juha Nurmela, OH5NXO. The recent revisions of the Nokia MD50/MD59 NMT firmware and some TMF-1/TMN-1 NMT firmware revisions have been written by Vesa Tervo, OH3NWQ. The Benefon Forte and Mobira MC25TAKSI firmware are written by Pekka Kotilainen, OH1ZJ. We give our sincere thanks to Pekka, who was the very first Finnish ham to write special firmware for commercial equipment, for his pioneering work. All information found on these pages or on our FTP server are copyrighted by the origininator and OH3TR.

The use of the firmware and documents found on this server is strictly limited to non-commercial applications by licensed radio amateurs. Please remember that performing the modifications explained on these pages usually invalidates the type approval of the equipment in any other service.

We would like to give our sincere thanks to the people who have helped us in translating the Finnish documents and pages in other languages. Look into these pages often for updates. When the English documents start to appear, we'd like to have someone translating them further in e.g. Swedish to help the Scandinavian hams with their conversion jobs. Our special thanks go to OH8JEP for his work for the French, Italian and Spanish pages.

The background picture © Juha Kurkikangas 1986

Mobile and portable equipment

Benefon Forte TDM-10N (NMT450) and TEM-10N (NMT900) car phones
Benefon Class NMT450 car phone with a cordless handset (TDM-10N/TEB-20 and TDC-10Z)

The notes on these pages are made for the Scandinavian NMT versions of Benefon Forte. However, they may also work in other versions, like TDM-10K (the 420 MHz NMT version found in Croatia and some other Balkan countries).

There is also a variant of Forte with a CT1 cordless handset. The earlier ones (TDM-10N with a separate TEB-20 CT1 base station) are called Benefon Class I. The NMT part is an ordinary TDM-10N and can be used with the usual Forte handset as a amateur rig. The ham firmware does not support the cordless handset yet. The later Benefon Class II (TDC-10Z) is a completely different design.

Benefon Forte can also be configured to operate as stand-alone FM repeater with the ham firmware.

  • Setting the courtesy tones in repeater mode by OH2LAK (Finnish)
  • Firmware and some Finnish notes
  • Benefon Forte 450 (TDM-10N) modification notes in Swedish by OH6KUM
  • Pictures of Benefon Forte by OH2LAK
  • Pictures of Benefon Class by OH9MBS

  • Mobira HC17(150 MHz)/HD17(450 MHz)

    This is one of the most bulky and battery hungry computer controlled handheld that has ever been made. It has been confirmed Y2K compatible, though.

  • The factory guys have made a a ham firmware for HC17. It works for the European 25 kHz spaced channels. The firmware can also make the UHF version (HD17) to work, but the division factors and the display are according to the VHF version.
  • A sort of user manual in Finnish.

  • Mobira R20/R21 (Philips PRM8010/8020)

    The Mobira R20 series is an OEM mobile PMR phone made by Philips. It is just the same as PRM8010/8020.

  • Modification notes in Finnish by OH6MLD.

  • SRP24 (Nokia SV1330)

    Salora SRP24 (Nokia SV1330)

    Salora SRP24 is the crystal controlled predecessor of SRP25/MC25/RC25 series. You can calculate the channel crystal with the following equation (use crystal specification SAL9):

  • SRP24 directory

  • MC25TVL control head

    Mobira MC25PTL/TVL/EVH (this is the one where all this fuss started about)

    All these are pre-trunking dual mode PMR/car phones made in 1984-88 for the Finnish PTT (PTL) and the Finnish Road Administration (TVL).

    There is also an office set for the radio. Greetings to Ossi at the Raisio Road District!

    The PTL/TVL/EVH has also been a good platform for 6 m, 70 cm and 23 cm radios:

  • MC25PTL/TVL/EVH-MC25PTL directory
  • PTL/TVL/EVH-koneen The latest firmware version 3.3
  • Readme v2.8
  • Info file v3.2
  • Info file v3.3
  • Tuning hints in Finnish by Timo Patana OH6NVG
  • Connecting a TNC by OH3XQ M$ Wurd-document and PDF
  • Using some SRP24 series channel crystals in the PTL calling channel receiver and in the TVL simplex receiver
  • PTL/TVL-koneen MC25PTL 6 metre directory
  • PTL/TVL-koneen 6 metre modifications by OH5HOI (in Finnish)
  • MC25PTL/TVL/EVH E2PROM loader MobyDick for a DOS PC with modification notes, used with the v3.3eeprom firmware version. NOTE!!! This firmware version is used with an electrically erased PROM like 28C64. The firmware version for ordinary EPROMS like 2764 or 27C64 can be found here.
  • Pictures of a PTL/TVL/EVH.
  • Finnish user manual for version 2.9 by OH1HEK
  • Finnish user manual for version 3.3 by OH4KJU:

    There has been a PTL-lookalike for the Finnish PTT obsolete Taxi network. The firmware is not compatible with the PTL/TVL/EVH series but OH1ZJ has written a repeater firmware for the TAKSI version.

  • MC25TAKSI modification directory
  • MC25PTL modification note in Swedish
  • MC25UK

    A similar looking radio has also been made for the UK S4 network. The logic boards seem to be a close relative to MD25NMT (Combi/Senator/Quattro).

    Salora/Mobira SRP25/MC25 (for ARP network in Finland)

    There have been more than 20,000 Salora/Mobira 25 series phones that have been manufactured for the Finnish PTT 150 MHz ARP public mobile telephone network:

  • SRP25S/CA (rotary channel switches, simplex, no automatic channel search)
  • SRP25S/CAA (rotary channel switches, simplex, automatic channel search)
  • MC25SA (same as SRP25S/CAA, later versions)
  • SRP25D/CAA (duplex, automatic channel search)
  • MC25DA (same as SRP25D/CAA, later versions)
  • MC25SN (user head with channel buttons, simplex)
  • MC25SN (user head with channel buttons, duplex)
  • These radios have also been marketed under the name of Televa, e.g. Televa SV1381.

    Most RF tuning notes apply to most Salora/Mobira 25 versions.

  • OH1NPK (RyydLab) has made a EPROM channel converter for the 25 series. The boards can be bought from RATS Parts Service.
  • Setup and programming of the channel converter.
  • SRP25/MC25/RC25 2 metre channel converter EPROM images
  • SRP25 and MC25 ARP phone modifications in FInnish by OH6HNC
  • An S meter for 455 kHz IF by G7SDC
  • Directory for modifications of SRP25 and MC25 ARP (150 MHz) phones
  • Salora/Mobira SRP25S/SNO ja D/SNO

  • SRP25 UHF directory (450 MHz MTD SRP25 phones in Sweden and Norway)

  • RB25/RC25/RD25 PMR versions

    Older 80/150/450 MHz PMR phones (Salora SRP25 or Mobira RB25/RC25/RD25)

    The RF boards of the 150 MHz equipment are very close to the ones in the SRP25/MC25 ARP phones.

    RB25/RC25/RD25 with the button head (ARTS 1 system)

    A lot of these phones have been available in Finland through the regional phone companies.

  • RC25 directory
  • An article about RC25 modification in Finnish by OH2BGN.

    Mobira RC25/RD25 with CS90 processor head (ARTS90 system)

    This is the last version of the 25 series phones from the late 80's. It has a Z80 processor inside the control head.

  • RC25/CS90 directory
  • RC25/CS90 modifications for 2 metres in Finnish by OH8HBG, OH8WM and OH8HMX
  • Nokia SV1300 S/C-2M

    Most of the Nokia SV1300 S/C-2M units in service are now owned by Mr. V. Chernomyrdin. Some new old stock units have been acquired by hams in Finland.

  • SV1300 S/C-2M-directory
  • SV1300 S/C-2M-modifications in Finnish

  • H40 portable

    Nokia HC40 (150 MHz) / HD40 (450 MHz) trunked portable

    Also known as Key Radio KP80T/KP150T/KP225T/KP450T and Kyodo KG109T

    This one is the earlier KG109 trunked version with the Fylde Microsystems processor board. It has a strange 27C128 EPROM that is connected to the board with two lengths of flexible PC board. It was also marketed in the UK by Key Radio Systems as KC450HT. There has also been other band versions like KP80T, KP150T and KP225T by Key Radio.

    In Finland, HD40 UHF portables have been in use in the 440 MHz AutoNet trunking networks. A batch of "new old stock" units has also been sold to radio amateurs. We don't actually know all the places where Nokia HC/HD40 and Key Radio KP80/150/225/450T radios have been used abroad. If you have any info, please tell us.

    The conventional PMR version of Kyodo KG109 has also been available in many OEM versions like in the UK (Key Radio KP80/KP150/KP450), in Australia (Sawtron KG-109) and in Germany (Grundig FK109). Some of you may also have spotted a KG109 playing a very important part in the movie "Police Academy 4".

    The firmware is currently available only for the HD40/KP450T 70 cm and the KP80T 4 metre versions. We may be able to add other bands (2 metres and 220 MHz) if somebody supplies us at least the schematics. Please contact us if you have information to share.

  • KP80T directory
  • The latest KP80T (4 metre) firmware release (2.0)
  • HD40/KP450T directory
  • The latest HD40/KP450T (70 cm) firmware release (2.0)
  • A short user manual by OH6MLD
  • Many aftermarket battery companies have packs for KG109. At least Akkushop in Germany, Uniross in South Africa, Alexander Technologies and Battery-Tech in the USA list KG109 on their pages. Try Google Search for other sources. Also Key Radio Systems sell new battery packs for the radio.

    H45 portable

    The microphone/speaker connector is also hard to find. One source is Imtradex in Germany (mic connector for Grundig FK 109, catalogue number 1018 002). Please remember not to connect either of the speaker wires to the chassis if you use KG109 e.g. on packet radio!

    IMARK Communications) in .

    Look also at G6IGA's excellent Key Radio conversion pages for more info about standard KP80/KP150/KP450 and other Key radio products.

    Nokia HC45 (150 MHz) / HD45 (450 MHz)

    There is also another, more recent KG109T trunked version. This one has also the processor board made by Kyodo. The radios were sold by Nokia as HC45 and HD45. The firmware is uploaded to an EEPROM with a serial cable from a PC. The ham firmware is in the works and will be available here some day.

  • H45 directory

  • R40 series mobile

    Nokia/Mobira RC40 - RD40

    RC40 (150 MHz or 230 MHz) and RD40 (450 MHz) are the latest mobile radios for trunked networks from the Nokia PMR division. These radios are designed to fit in the standard DIN car radio space and they sport a large LCD display in the CU43 control head.

    Sorry, no ham firmware yet, but these beauties are certainly worth taking. They can be programmed with enough ham channels with the original trunking firmware if you have the PC program or the CU43PROG service control head. The user interface is a bit awkward, though.

  • R40 directory

  • R58 series transportable

    Nokia/Mobira ActionMan RB58 (80 MHz) RC58 (160 MHz) RD58 (450 MHz) trunked transportable, Computec RB660 (Mobitex)

    This radio looks like a Mobira Talkman cellular transportable. The only thing in common between the Talkman and ActionMan series, however, are the case and handset mechanics. The R58 radios were designed by the Nokia/Mobira PMR division for Mobira ARTS PMR systems and Nokia ActioNet and other MPT 1327/1343 trunked networks.

    Most of the units have appeared under the well-known brand Nokia but some very early ones carry the original Mobira legend on the handset.

    This is one of the radios you must have. It has a wideband receiver that covers all public frequencies and it runs hours without an external DC source with the piggyback 3 Ah or 6 Ah gel cell battery. The car kit has provision for an external PTT and a goose neck or sunvisor microphone. All units are rated for 15 W key down, even battery powered. The ham firmware supports now DTMF encode, CCIR encode/decode and 1200 bps AFSK selcall that is not easily recognised with any available decoding software. It is also your personal repeater just by a flip of a software switch.

    The band versions are RB58 (80 MHz), RC58 (160 MHz) and RD58 (450 MHz). Besides conventional simplex/semiduplex units, also duplex versions were manufactured for 150 and 450 MHz.

    What we know of, RC58 radios have been delivered e.g to the UK JRC band networks, Azores and Sierra Leone. RD58 radios can be found anywhere, e.g. in the Dutch Traxys and the German Chekker trunked networks.

    The simplex units are very easy to modify, you'll only have to install the ham firmware EPROM and configure the set with the keypad. There are also duplex sets on the market which need a PIN diode antenna switch and antenna filter board or a relay/filter combination instead of the original duplex filter. It is also recommended that in the UHF versions (RD58) a true noise squelch board is installed, at least when the radio is used in a hostile RF environment.

    Computec RB660 is a Mobitex mobile unit with a different processor board. There are both 80 MHz and 150 MHz versions available.

  • R58 directory. Please note that the earlier firmware versions (1.7 and older) have separate images for different bands. From version 2.0 onwards, one image fits all
  • A product line guide to the numerous versions of Nokia R58 series transportables
  • A product info guide for R58 series with pictures of all modules inside the radios and all accessories
  • A short tutorial to the user interface of the RB/RC/RD58 by OH6MLD, revised for firmware version 1.6 by OH3BK
  • . For versions 2.0 and later, please see the info files.
  • A simple PIN diode antenna changeover and antenna filter board by Petri Kotilainen OH3MCK (a better substitute for MI402 is Philips BA482/483)
  • Another PIN diode antenna changeover and antenna filter board info
  • A true noise squelch board for RD58/BD58 by Markku Rantala OH6MF, schematic diagram and parts layout
  • Changing the VCO tuning range in RD58*B models (440...470 MHz) to help some lock problems on the 70 cm amateur band, by Vesa Tervo OH3NWQ
  • Handset modification for clearer modulation by Petri Kotilainen OH3MCK
  • An English modification note for RC58S (UK JRC band version) by Ken Hewitt G8PWC
  • R58 as a repeater

    R58 series mobiles can also be used as a repeater.

    The OH5NXO ham firmware has now built-in repeater functions like timers, callsign generator and total FSK remote control of all parameters with another R58 mobile. Unlike the earlier repeater firmware, it works with both processor boards.

  • Repeater modification notes for R58 series by Pentti Gronlund OH3BK

  • MD50/MD59/ME59 NMT transportable

    Nokia/Mobira Talkman NMT450/900 transportable

    Nordic versions like MD50N, MD50NA, MD59NB, ME59NR etc.

    The firmware and modifications are intended for Nordic NMT units that are found in large amounts in all Nordic countries. The NMT450 phones can also be found in e.g. the Czech Republic (MD59CZ), Holland (MD59LS) and Hungary. The NMT900 versions can be found in Switzerland and in Holland (ATF3 network). Units with similar appearance can be found in various networks all over the world.

    The NMT450 versions make an excellent 70 cm rig which also behaves very well on 9600 bps packet. The NMT900 version can be converted to 23 cm with some hard work and dedication.

    We also believe that the NMT900 version could be used on the US 33 cm band (902-928 MHz) by only substituting the duplexer with an antenna changeover/filter board and the RX ceramic RF filters (935-960 MHz) with appropriate ones (preferably tunable helical filters from e.g. Toko).

  • OH3NWQ has written a user manual in English.
  • MD50 directory (older NMT450 version)
  • MD54 directory (German C-Netz version)
  • MD59 directory (more recent NMT450 version)
  • MD59 modification guide in English (draft version)
  • Some MD59 information in Italian and Spanish by OH8JEP.
  • MD59LS (Dutch NMT450 version) modifications for 70 cm and 23 cm by PA3GCO.
  • MD59 modifications by OK2XDX in Czech, contains lots of schematic diagrams.
  • ME59 directory (NMT900)
  • MD94 (Talkman 510 NMT450)

    MD94 was designed to be installed in the standard DIN car radio slot. It is the successor of the Talkman 50/59 series. The first revision of the ham firmware is now available on the server.

  • MD94 directory
  • TMF-1

    TMF-1 (Talkman 520 NMT450) - TMN-1 (Talkman 620 NMT900)

    520 and 620 are the look-alike cousins. Both are very easy to modify, TMF-1 for 70 cm and TMN-1 for 23 cm.

    In the first versions (TMF-1/TMN-1) the executive is stored in an EPROM. These are the easy ones. The later versions (TM*3, TM*4)do not have an EPROM, they use a mask programmed processor (H8 ZTAT-CPU) that must be replaced. The chip is not available anymore. The RF parts are interchangeable in the -1 and -3 series so you can e.g. take the processor/audio board from a TMN-1 and the RF boards from a TMF-3 and make a radio for 70 cm. The RF parts of the -4 series are physically different so their main use is as a source of spare components.

    The firmware by OH5NXO works only with the TMF-1/TMN-1 versions and the HSN-2 handset.

    OK2UCX has written another firmware for the later HSF-2 handset. This is one of the later handsets with a special OTP processor. The firmware can be programmend in the free upper blocks of the EPROM.

  • TMF-1 directory (NMT450)
  • TMF-1 70 cm modification notes by OH3NWQ
  • TMN-1 directory (NMT900)
  • TMN-1/HSN-2 23 cm modification notes by OH3NWQ
  • Some TMN-1 schematics with modification notes
  • There exists also another firmware and English modification notes for TMF-1 (70 cm) by Pavel, OK2UCX. This one is intended for packet radio use with no handset control functions.

    The modification notes for the French 450 MHz Radiocom 2000 network version appear on the F5SOH pages.

    Mobira Cityman

    Mobira Cityman NMT handset "Gorba"

    CD60 (Cityman 450)

    There is ham firmware available for the early Nordic NMT450 "Gorba" version (CD60NN).This does not work in the later versions (CD60HN) or in the NMT900 version (CE61NN). The picture shows the CD60HN version. The main difference is the long SEND/END button, all buttons in CD60NN are of the same size.

  • CD60 directory (Gorba NMT450)
  • CE61 (Cityman 900)

    Firmware for CE61NN (900 MHz to 23 cm) will appear here later.

  • CE61 directory (Gorba NMT900)

  • Other brands

    AP Radiotelefon (Philips)

    AP700 and AP2000

    AP2000 is a nice little synthesized Danish PMR phone from the late 1970's. There are VHF and UHF versions available. AP700 was its crystal controlled predecessor in the early 70's. Later they intorduced also a 100 channel synthesized AP700.

  • AP2000 directory
  • Channel EPROM board with 1750 Hz tone call for AP2000 by OH4MVH
  • OZ2CPU has created two nice pages which in our opinion should be called "Everything You Ever Wanted To Know About AP700 and AP2000"
  • AP4111 (NMT450) and AP4112 (NMT900)

    These were quite popular transportable phones in the Nordic countries' NMT networks. There is a free Finnish firmware available for AP4111 (70 cm) which will later cover also AP4112 (23 cm).

  • The most recent software updates and modification notes are now available on the OH8JEP AP4111 pages
  • OH3TR AP4111 directory
  • OH3TR AP4112 directory

  • Ericsson

    Although Ericsson has been a market leader in the Scandinavian countries for decades, the amount of conversion information available from Sweden is zero so far. We'd be delighted to get some on the server. There have been rumors from Sweden that a ham firmware for the Ericsson Hotline 430-series transportables is in the makes.

    Ericsson has later bought GE in the States so some information is available by the US hams for the GE/Ericsson radios that have been made there.

    Philips PMR

    You can program the Philips/Simoco/Pye FM1000/FM1100/FM1200 series PMR radios for amateur use just by changing the (E)EPROMs and some resistors/caps. See the FM1000 Pages by Gerrit Speelman, PA1MT, for more information. On the pages you can find free firmware written by DL2ECT and PA4DEN.

    There is also a FM1000 mailing list at

    Join it if you are interested in Philips conversion.

    G4HJW shows how the 68-88 MHz version of FM1000 can be cajoled to 6 metres.


    Danish Storno, owned nowadays by Motorola, is a well known name in the European PMR market.

  • The Unofficial Motorola/Storno Programming Site
  • Some modification notes for Stornomatic 900 of Danish origin
  • Storno CQP4000 pages by PA3DBJ
  • Storno conversions by G7SDC

  • Motorola (USA) and GE/Ericsson

    Lots of Motorola and GE information is available in the States and in the UK. Unfortunately no special ham firmware has been written for the radios so you have to keep up with the awkward PMR user interface.

  • Michael Wright has written comprehensive Motorola HT-220 pages. Recommended especially to those who think a Nokia HD40 is too large to carry.
  • The Unofficial Motorola/Storno Programming Site, also notes for other radios popular in the UK.
  • A Motorola GP300, GM300 and MC Micro modification site by G1IVG
  • A Motorola MC80 modification guide by G3VMW
  • BatLabs is the place to go if you have one of the Motorola PC programmable models, also an interesting Motorola Gallery
  • WN6CTY offers help to some of Motorola synthesized versions
  • The Repeater Builder's Technical Information Page with lots of Motorola and GE modifications (Kevin Custer W3KKC)
  • Motorola and GE modifications (Southeast Iowa Technical Society)
  • NHRC has some GE MASTR II modifications to offer besides a repeater controller that fits inside the radio
  • GE Tech (Hall Electronics)
  • GE MASTR Executive II modifications and conversions (Ray Vaughan, KD4BBM)
  • The 1 Stop GE Mastr II Conversion Site (Kevin Custer, W3KKC)

    Base station radios

    Nokia BB/BC/BD58 and BC28 base stations

    This is the later base station radio in the Nokia analogue trunked networks. It is basically an R58 series mobile with a high power PA installed in a heavy duty die cast case with a lots of fins.

    The easiest way of making a repeater of a B58 series base station is to substitute the main board with the P8N/P8E processor board and a A8N audio board taken out of an R58 series mobile. Another way is to build a channel loader board for the original configuration and use some of the many repeater logics available.

  • B58 directory
  • A version guide for the B58 series base stations
  • A channel logic board (TNX OH5NOL, OH3WE ja OH2LAK).
  • BD58 repeater guide in Finnish
  • Some speculations in Finnish about the isolation between the antenna ports of a BD58 repeater
  • An English guide of modificating the R58 series mobiles for repeater use
  • BD58 RX and TX measurements in Finnish
  • A real noise squelch for RD/BD58 (equipped originally only with RSSI output), schematic diagram and parts layout

  • Nokia BSR80/BSR150/BSR230/BSR450 base station (Kyodo KG110/Key Radio KF450)

    Some of the early Nokia Actionet networks have been equipped with Kyodo KG110 series base station radios.

    The BSR series base stations are rugged 19" units. There is even a channel logic built inside. You'll only need a repeater logic board to make a repeter of a Nokia BSR/Kyodo KG110/Key KF base station.

    Most Nokia BSR/Kyodo KG110 base stations found in Europe are built for a 12.5 kHz channeling. Filters for 25 kHz channeling can be had from Key Radio Systems in the UK.

  • See the BSR directory for e.g. the channel EPROM converter by OH2BGN.
  • A picture of a BSR base station (151 kB)
  • A guide to Nokia BSR versions
  • Kyodo KG110 versions to Nokia BSR versions (available soon)
  • BSR450 modifications in Finnish by OH5HOI

  • Radiosystem

    Swedish Radiosystem has manufactured NMT base stations for networks in e.g. the Nordic countries, France and Holland.

  • PA4DEN sells a ham software for Radiosystem RS9044 NMT450 base station
  • Some RS9042 (Radiocom 2000) modification notes can also be found on the French modification pages (

  • Some useful things in modification work

  • Willem in Holland has built up an universal EPROM and PIC burner. Do we have to tell more?
  • Using the Nokia/Mobira 24/25 series 9 pin connector in packet radio...ssshhhhh....
  • A 2m/70cm diplexer
  • by OH3MCK
  • Another 2m/70cm diplexer by OH6KXL
  • Where is the guy who is keeping all the surplus test and measurement equipment in his garage? Please contact us if you're in need of some good customers!

  • All the rest

    All professional made radios are worth of taking, sooner or later. But if you think you're going to make a good profit, none of the radios presented on this page are worth it. Sorry, we recommend pork belly futures or whatever...

    Links to some soul brothers:

  • Nokia MD59LS modifications for 70 cm ja 23 cm by PA3GCO
  • Danish modification pages (, mostly commercial ham radio products but also Motorola, Storno, Bosch jne.
  • Key Radio/Kyodo pages by G6IGA
  • PMR modifications by G8YOA
  • Conversion notes by Amateur Radio Experimenters Group in Australia
  • Siemens C5 Netz C modification for 70 cm (DL6INT, in German)
  • The French Modification Pages, lots of things found in the French SFR NMT and Radiocom 2000 networks
  • The ex-PMR Resource Page, a very comprehensive link collection by M5GWH
  • Museum voor het Radiozendamateurisme Jan Corver, lots of info about Nokia, Bosch, Teletron, Radiosystem etc.
  • PA3BYA has written some modification notes for Bosch KF161
  • East London Communications (Duncan, G8KNF), lots of surplus radios for sale. Also programming cables (Motorola, Philips, Icom etc.)
  • Quokka's Sawtron Museum, a nice virtual museum of Kyodo equipment also sold in Australia under the name of Sawtron
  • Rune's LMR Links, a place where you can find all PMR manufacturers on the earth
  • Trunked Radio Forum is a nice place to stop
  • Many hams interested in converting commercial equipment are also repeater keepers. Our Repeater Pages contain lots of links to repeater information. The pages are in Finnish, but most of the links refer to sites in English.

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