Ed, that's a cool device, but it says it only passes CPC, it doesn't generate one. Both CPC generators I mentioned will provide a CPC from silence, busy tone, reorder tone, dial tone, and even DTMF tones. The problem is the cost. The affected line goes instantly back to dial tone, and if you leave it off hook long enough it goes to reorder and eventually to howler tone. I could use one of the CPC generators, but 75-90 bucks just so I don't have to keep an eye on line lights.... I'm still trying to get these fools to fix the damned device. They haven't said they won't, and they did say they were going to replace it. Time will tell, it's to soon to tell if that was BS or not. If it turns out I'm stuck with this thing with no CPC, I'll start evaluating my options. I may get the CPC generator, I may can the service, and I might just suck it up. I don't want to do the third thing, because that's just another win for outsourced tech support. It's a pretty sad state of affairs that someone can be so brilliant to come up with the fancy electronics we have today, only to be made useless because companies won't pay for tech support that actually knows something about the product they are supposed to support.