I have limited basic with Comcast in New Britain, CT (near Hartford). I get the locals, QVC and The Weather Channel (national feed) in HD. I also get The Weather Channel (local crawl and conditions) in SD. Other services include many broadcast subchannels, TBS, NECN (Boston regional news channel), C-Span, CT-N, HSN and the so-called P.E.G. access channels.
With strictly an antenna, I'd only get the following:
WFSB-TV (CBS) channel 3 Hartford [digital 33]
WCCT-TV (CW) channel 20 Waterbury [digital 20]
WEDH-TV (PBS) channel 24 Hartford [digital 45]
WHPX-TV (ION) channel 26 New London [digital 26]
WVIT-TV (NBC) channel 30 New Britain [digital 35]
WCTX-TV (MY) channel 59 New Haven [digital 39]
WTIC-TV (FOX) channel 61 Hartford [digital 31]
Notice who isn't on that list? WTNH-TV (ABC) channel 8 of New Haven [digital 10].
Here's my other issue. I live in the south end of New Britain, CT, at the bottom of Walnut Hill. (That same hill is home to The Hospital Of Central Connecticut and Walnut Hill Park.) It hinders my reception of anything from Avon Mountain. Channel 3 is there about 95% of the time and that's only because they're at a full 1 million watts ERP. The same site has WUVN-TV (UNI) channel 18 of Hartford [digital 46]. It always breaks up and is rarely reliable to watch for more than a few minutes. I NEVER got a reliable signal from channel 18 in the analog days. Channel 24 was the same way until they moved their site to Rattlesnake Mountain in Farmington, about a year before the 2009 analog TV cutoff. The signal was like night and day! The only indoor antenna which ever got a decent signal of WTNH-TV was a so-called RCA Batwing one. I had to rest it vertically, having it sit at the top of my south-facing second floor bedroom window.
Sometimes, when I aim the antenna towards New London County for channel 26 (ION), I'll get a bit of WPXQ-TV (ION) channel 69 [digital 17] of Block Island/Providence, RI. That transmitter is in Exeter, RI, fairly close to the Connecticut state line, putting it only a few miles further than the channel 26 site in Montville.
I used to get a snowy color signal of WEDH-TV (PBS) channel 53 of Norwich, CT. I lost that completely when they went to VHF channel 9 for their digital (it was more reliable than channel 24 was from their old Avon Mountain site).
I don't receive any signals from Springfield, MA on digital. Period. Analog channels 22, 40 and 57 were never clear here, whether they transmitted from Agawam, MA (channel 22) or Holyoke, MA (channels 40 and 57).
Lastly, we once had an antenna in the attic, which my late grandfather may have installed. We've never had an antenna on the roof itself. My landlord won't allow one to be put up there either.