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Quintum Tenor D3000 E1 impedance

Viewing 7 posts - 1 through 7 (of 7 total)
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  • #25580

    I have a Tenor D3000… my PSTN provider delivers through BNC coaxial, 75-ohm. In my Tenor D3000 configuration the E1 impedance is set to 120ohm(1). Does somebody know how can this be changed to 75 ohm? And… in the event that this is not possible, what are the possible consequences of having the PSTN E1 set to 75 ohm and the Quintum to 120 ohm?


    You should use a ballon, means a little passive devoce that have a RJ45 conector on one end and a coaxial BNC conetcot on the other.

    They should not be too expensive, and inside the device there is a impedance matching component that will do the conversion from 120 to 75 ohms.

    This device looks just like a oversized coaxial conector with a RJ45 conector on the other end.

    There is no much loss if you somehow managed to connect the coaxial to the gateway, but there is another issue. I think that the gateway is a balanced input anf the provider is unbalanced (one hot wire in reference to ground)

    It may work, but you will be a good antenna for any discharge coming trough the phone lines.

    Teodor Georgiev

    I remember that in the Dxxx CLI under the config -> line menu, there was an option named “e1impedance”. Look for it.


    Noname, Thank you for your comments, I just got the converter. You cleared most of my doubts.

    Teodor, Thank you too. I appreciate. While there is an option in the config -> line print that shows E1impedance, there is no command to change it, at least not that I have found. Any ideas? Thank you again.

    Noname to Alberto

    Glad to be able to help.

    I do not know why Quintum does not ship them as part of the equipment.

    Could I ask where are you located and how much did you paid for them???

    I heard of some people really ripped off on the price of those ballons.

    best regards!!!!

    Alberto to Noname

    I got it from a friend that happen to had one, at no charge, but I have heard they cost around $60 USD. This is the website for the company that build the one I have, and works well:


    Ouch!!! $60 dollars for that!!!

    I always wandered if the adapters used to convert the old coaxial used on the early days of ethernet will do the same job.

    I have pounds and pounds of that stuff just lying around.

    Anyone on the U.S. that feel like trying it out????
    I could ship few out with the understanding that you will post the results.

    Thinking it over, if you are on the US, you will not need it.

    Just an idea

Viewing 7 posts - 1 through 7 (of 7 total)
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