Originally Posted by sebenste
Trip's Inverness, IL bandscanner is picking up a decent signal on rf channel 30, and the error rate is good...yet there is no call sign as to what that is. I tried to tune in channel 30 tonight, but couldn't get a signal 40 miles away. No out-of-market signals are currently coming in...I'm curious as to what that is.
I made a few changes to the antenna system the other day and you'll see that in the bandscan link
. I tried a HD-7696 and ended up going back to the CM-2020. I also use a AP-8700 preamp. The antenna is in the attic. This night of experimentation confirmed a suspicion I had a long time ago about the 300 to 75 ohm balun. If you have one of those channel master baluns with the leads that don't have a fixed distance (i.e two diverging wires from the plastic housing) between them THROW IT OUT! I found an older RCA balun with the standard short 300 ohm transmission line to the balun housing and it works at least 3-4 dB better. It's not terribly much but it really matters for stuff that is barely decodable. Also, strangely enough it dramatically improved the WTTW reception. I'm guessing that impedance mismatch with the leads kind of spread out to "about" the distance for 300 ohms was not good enough, especially at RF25.
As you can see, I had to decide whether to get WRJK or WYIN and I chose WRJK. WRJK is just above the decoding limit.... and yes, their signal really sucks. They won't cut it as a legitimate broadcaster if they don't get a power increase. If they can go to 1kW that would help immensely. As it is, the directional signal really does no favors for the North Shore or those in the northern suburbs. Their UHF signal was significantly better.
Now, I also found some good data from http://dennysantennaservice.com/hd_s...enna-html.html
. There is a link in there
with a table comparing his stacker antenna to the one I use and several others and his is much better. I would go ahead and purchase one if you are considering a new outdoor or attic antenna.
Use the rabbitears.info site and Google Earth Pro. Draw a line from your house to the transmitter and get your precise bearing from that. What you'll find is you may have to deviate on that slightly depending on avoiding nearby lossy/reflective objects.
I know the temptation is to buy some cheap and cute antenna from Best Buy or Walmart but don't take the bait. Spend a hundred bucks, if you can, and get something respectable. Also, look at the specs on the preamps and don't buy something that does not have good overload signal protection (meaning amplifiers with a higher 1 dB compression point) and a low noise figure. The Winegards have been pretty good about that. The ChannelMasters not as much. I guess I am partial to the Channel master antennas and the Winegard amps though that stacker antenna may displace the Channel master from what I have read.