Well, I already have 2 analog tuners and 1 digital tuner, now I want to add another digital tuner, would I have to install another antenna? or can I split the current one I have into the two digital tuners??? also what would you recommend for a third card I currently have
Hauppauge WinTV PVR PCI II (26xxx)
Hauppauge WinTV HVR-1600 NTSC/ATSC Combo
does hauppauge make a single digital tuner only??? or should I can the PVR PCI II and get another HVR 1600??? and would there I have to do the registy hack for that since it'd be 4 tuners?

I have 6 ATSC tuners running off the same Channelmaster 4228 antenna...  As long as your antenna is good enough (has a strong enough signal) to survive the split(s), you'll be OK.  Each split lowers the signal - that value will be printed on the splitter itself...

Same here.. I have mine split by three... If your signal strength is high in the tester you should be fine.  I use a cheap amplified antella... was like 35 bucks at circuit city.

good deal. Now is any splitter fine? or do I need something specific to digital cable???

one more thing that has me a bit confused, I have never done a registry hack or anything and I already have 3 tuners 2analog 1 digital.....and they all work, whats the deal?? is it because one is digital???

I am running 2 HVR-1600 (thats 4 tuners 2 cable (analog) and 2 digital (Free OTA HD) right now with no issues on the same antenna.

If I were to do it over I would have one HVR-1600 and one HVR-1800.
Why? Because the 1800 has FM radio built right into it which configs with vista durring setup and its a PCIexpress X1 card, for me that frees up a standard PCI card slot.

Yes, Media center supports 2 analog and 2 digital for a total of 4 without any modifications or hacking of the registry.

awesome, wish I wouldda found this place sooner than I did...wouldda saved me alot of headaches....well off I go to spend more money.

Thanks again guys.