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muradt
06-30-09, 08:53 AM
Hi,

Is it possible tapping PrimeNet board to 75 ohm line (BNC) for digital logging? Or I should convert 75 ohm line to 120 ohm and then tap to 120 ohm lines?

many thanks beforehand,
Murad

rboileau
06-30-09, 09:00 AM
Hi Murad,

The PIKA E1 lines are set to 120 ohm - RJ-48 Twisted Pair.

You will need an external converter to tap 75-ohm lines.

I have just googled with "75 ohm to 120 ohm converter" and several adapters are available on the market to buy.

CONNECTOR A : 8 pin RJ-48C connector on the 120-ohm side
CONNECTOR B : Dual BNC coaxial connectors (transmit and receive) on the 75-ohm side

Best Regards,
Rod

muradt
06-30-09, 09:11 AM
Hi Rod,

thanks for VERY quick response! ;-)

Then connection scheme for audio logging should be like this:
tap to 75 ohm customer e1 line -> make conversion to 120 ohm -> PrimeNet ??

Is it right ??

I ask you because of impedance of digital logging cards are 900 ohm.

Murad

rboileau
06-30-09, 09:19 AM
Hi Murad,

My pleasure.

That is correct.

The PIKA E1 line is balanced at 120 Ohms. On the digital logging version of the PrimeNet MM DL board, there is a high impedance circuit so that the tap does not affect the monitored line.

Rod

muradt
06-30-09, 09:27 AM
Then I will test as follow: tap to 75 ohm line -> make conversion to 120 ohm -> connect to PrimeNet board.

Many Thanks! ;-)

muradt
07-02-09, 02:29 AM
Hi,

I got it running with converter box (75 ohm <-> 120 ohm).

thank you Rod ;-)