On Fri, Feb 18, 2011 at 2:04 PM, Bruce N <[email protected]> wrote: > I have sent you the file I recorded from the Tx stream and converted it to > a format that can play on VLC Media Player. > > Interesting. It's a sawtooth wave, not a sine wave. Not that it matters I guess but I would have bet on a square wave.
The pitch variation only shows up when you play it in VLC. If you play it in Audacity, there's no pitch change. That solves one of the mysteries of "why would a Milliwatt have frequency drift". I can still see the reason for Milliwatt tests. Even though you've got a digital circuit, you could be putting that into a channel bank and terminating on analog circuits. I agree thought, I can't think of much use for it in testing a PRI. It's TDM, if your timing is ok, your frames are arriving intact and your signalling is setup right, you should have good voice quality. At least that's how I see it. I'd be interested to know how it works out. If I had to make a prediction, it would be that you tell Bell about the problem, the problem goes away and they deny changing anything on your circuit. One thing I'm not clear on is this: You say the problem goes away when the call is connected. Does the user hear this sound at all or are you recording idle channels? (I wouldn't have thought to try that or even though it was possible) Dave
