That was my very point a few weeks ago when I talked about the need for a pre-emphasis filter on the OT+ and T2 for those folk who use the data port vs the mic port. That is *still* needed. Some TNCs are very finicky about the low tone being higher than the high tone after passing through the de-emphasis filter. They won't decode at all!
Dale. KG5LT On Jul 10, 2009, at 6:51 PM, Bill V WA7NWP wrote: > > > > Just because you can hear it doesn't mean it can be decoded. A > bit of > > noise or excessive distortion can kill it. I was driving around > with my > > D710 over the weekend in a bad spot (bad spot for APRS that is, > great > > spot for camping and partying) and heard a ton of packets I > thought by > > ear should be decoded, and got nothing. > > That could be the pre-emphasis (most rigs) vs discriminator straight > audio (D7XX) issue. The digi you were hearing could have been just > far enough on the other side of normal that the D710 couldn't decode > the packets. > > Bill
