Thanks for your response Pete. We also produce E1 cards and do a similar thing to yourselves. However, we additionally superimpose a noise signal onto the looped back signal. >From your reply, I can see that this is over the top! Still, too late, the test equipment is now designed and in place.
The trouble with the basic rate rx sensitivity tests is that they are much more stringent than E1. The tests called up in ETS300 012 clause D.4.8.2 specify various levels of jitter, various bus configurations and various levels of superimposed noise. We already test to a cut down version of these tests (with BABTs approval) with the K1403 but we would like to eliminate the need for the K1403 altogether. It is difficult to know the minimum set-up that BABT will let us get get away with. I guess all we can do is put forward a proposal and hope that they go for it. >regards >David Sanderson >Aculab plc >[email protected] >---------- >From: Pete Van Raalte[SMTP:[email protected]] >Sent: 21 August 1996 15:31 >To: [email protected] >Subject: Re: BRI - rx sensitivity testing > >Dave, > >We have a similar problem on an E1 application (PRI physical layer). >BABT has permitted us to use the simple and inexpensive expedient of >looping XMT back to RCV through a 10 dB attenuator. If we get >error-free operation (no alarms), then we have proved receiver >sensitivity to BABT's satisfaction. I don't know if they would >accept this solution in a BRI application, but you might give them a >call to inquire. > >
