VoIP to ISDN (to use old ISDN phones over VoIP) ?

Discussion in 'UK VOIP' started by Martin Maurer, May 14, 2005.

  1. Hello,

    do someone know if there are VoIP to ISDN telephone converters ? I know
    there are VoIP to Analog Phones converters to use your old analog phone
    equipment over VoIP, but the same for ISDN (prefereable Euro-ISDN, DSS1, but
    all other also ok) ?


    Martin Maurer, May 14, 2005
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  2. do someone know if there are VoIP to ISDN telephone converters ? I know
    In Germany the most poular Voip to ISDN converter is the "Fritz!Box Fon WLAN
    " produced by AVM.
    If you would have a look at a german newsgroup you would see that any 2nd
    treat is about this device (the call it the FBF or the FBF 7050) - see

    This device is a combined DSL modem + router + wireless acces point + Voip +
    ISDN/analogue phone switchbox ...
    It contains 1 internal S0 bus (where you can connect your existing ISDN
    switchbox, or up to 8 ISDN phones)
    There are also 3 analogue phone connections, 2 network (RJ45) and 1 USB
    connection for your PC's and/or LAN ..
    On the incoming side you can choose between 1 analogue or 1 ISDN line
    On the VOIP side you can have multiple Voip accounts.

    The most common set-up for ISDN users is to connect the "FBF 7050" between
    your incoming ISDN line (NTBA) and your ISDN house installation. Then you
    can contuinue to use all your existing equipemnt (both analogue and ISDN)...
    Depending on the numbering rules you can setup to FBF to divert calls to
    VOIP or PSTN...
    Incoming calls (Voip, ISDN, fax) can be flexibely redirected to internal
    phones or MSN of choise

    I'm living in Belgium, and closely watch the VOIP discussion on 2 worlds: UK
    and Germany ... What surprises me the most is that - despite the
    globalisation - it looks like 2 complete different worlds if you read de.
    and uk. newsgroups....
    (Only common problem is sipgate ;-)

    Philippe Deleye, May 30, 2005
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  3. Martin Maurer

    Ivor Jones Guest

    Now then Philippe, calm down..! Nothing wrong with Sipgate at the
    moment..! Although now you've brought it up......!

    Ivor Jones, May 30, 2005
  4. I've ordered one of these from 1&1.
    I live in Germany and, since I am not aware of a German group, have been
    following this one. What are the main differences between the UK and
    Germany (apart from the prices---I'm assuming that, like everything
    except wages for most people, they are higher in the UK).
    Phillip Helbig---remove CLOTHES to reply, May 31, 2005
  5. I live in Germany and, since I am not aware of a German group, have been
    a German VOIP group is: news://de.comm.internet.telefonie
    I believe the main difference could be the ADSL connection, where basically
    there are 2 standards:
    "ADSL over ISDN" (also "Annex B", or "U-R2"), and "ADSL over POTS" (also
    "Annex A").
    POTS = 'Plain Old Telephony System'

    In Germany you allways need a "ADSL over ISDN" Modem, even in the case you
    have a analogue T-NET subscription, where in Belgium (and I guess in the UK
    also) you would need a "ADSL over POTS" Modem

    see also: <http://board.protecus.de/showtopic.php?threadid=7185>

    The Fritz!Box can be switched between Annex A and Annex B, see

    Philippe Deleye, Jun 17, 2005
  6. Martin Maurer


    Nov 7, 2008
    Likes Received:
    I found this thread because I am also looking for an Ethernet to VOIP to ISDN adapter.

    I tried the Fritzbox 7050 for months, and after overheating, applying heat-sinks based on very credible advice from the best local electronics professionals store in Berlin, Germany, Segor in Berlin (I could not take it off-line immediately), and later contacting AVM, they will not support the device after having initially said they would. Simply based on the flimsy excuse there have been heat-sinks applied to the overheating chips. These heat-sinks were removed on their request, and while they said they would tech it afterwards, they changed their position again and said they would not.

    An overheating product is an overheating product. Heat-sinks, applied then removed, do not change the innate problem of overheating.

    I have been in the computer industry for over 10 years, since the early 90's, and have rarely witnessed such poor support and lack of integrity by a company over a product, as I have seen from AVM.

    Furthermore, as hobbyists and professionals know, their groups are the first to innovate. The website ip-phone-forum.de, pointed to earlier, has received a nasty cease-and-desist letter from AVM's legal department, because ip-phone-forum's very technically literate users posted improved firmwares for various Fritzbox devices. The firmware for the Fritzbox devices is in duplicity: AVM releases it as open-source, for the positive publicity, but as soon as someone uses it to improve their product, AVM makes hostile legal action. It is supposedly 'open-source', and so invites innovation, and yet AVM sends cease-and-desist letters AKA the RIAA or MPAA? In addition, there is no warranty seal on the Fritzbox device, yet any hardware additions, improvements, only the addition of a small slab of removable aluminium, 'voids the warranty'.

    AVM's hostile legal action against such a large, well-intentioned and ethically-abiding community of people and AVM's lack of integrity, means this is a company to steer clear of. Else be ready to get no support, and be kicked to the curb as a customer.

    I can only recommend, if you must buy AVM, to buy it second-hand from eBay, not support AVM's retail sales, and not pay exorbitant prices for, what can be, junk with no support.
    Last edited: Nov 7, 2008
    moc.hooha, Nov 7, 2008
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