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Discussion Starter · #1 ·
Just so you experts like Glenn and Jerry have the backgroung on my situation I'm re-posting a thread I started a week ago. Based on my location, about 15 miles from the broadcast towers, do you think the CM 4228 Bow Tie would provide superior reception to the JBX21?


"Although my reception of the digital locals has been fine during the fall and winter, I always experience multipath this time of year. For backround, I live in a low-lying area but have a line of sight to the towers, and have a Zenith DTV1080. To try and combat the spring vegetation:


*I started out with a Radio Shack UHF-only yagi and rotor--regardless of the orienation of the antenna, I often have a couple of dropouts an hour on St. Louis locals KTVI, KMOV and KSDK. The strange thing is that sometimes I'll go days without any dropouts and then have several a hour on certain days. No obvious weather conditions seem to contribute to this mystery.


*Then, I bought the pricey Blake JBX21 yagi that's supposed to be great at multipath rejection. It really hasn't reduced the number of dropouts or multipath. This antenna may actually provide too much gain, since I'm within 15 miles of the broadcast towers. I've been searching for a sweet spot for all stations with my rotor to no avail. I've adjusted the tilt with no significant improvement."


Thanks,

Andrew
 

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Discussion Starter · #2 ·
Just to let you guys know, I tried the RS Double Bow tie today, with no success. Regardless of how I positioned the antenna on top of my TV, the signal would bounce from good to near 0 on all local stations. If my signal bounces from great to below 50%, when dropouts occur, isn't that multipath. If so, would the 4228 on my rooftop mast be suitable. Can wind blowing leafs and/or the antenna cause dropouts? I'm leaning towards the leafs, becasue I don't have any dropouts during wind in the winter.


Do you guys agree with this quote from a AVS member, "The bow/screen antennas are much better at rejecting unwanted signals/reflections from the rear(because of the screen)." Since I have alot of trees and leafs blowing behind the antenna, would the bowtie out-perform a yagi.


Thanks,

Andrew
 

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I have used the 4228 in many situations here in Pittsburgh. With our rolling hills we can get a lot of multipath. It has been able to pull in signals that I could not get with other antennas. But sometimes the height of the antenna will be sensative . I have had installs where raising the antenna just 6" went from the DTV1080 going from fair to dropout to good and locked! Antenna work can be more of an art than a science when you have hills and towers spread all around. Good Luck! :cool:
 

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Discussion Starter · #5 ·
Joe,


I wish you would have let me know sooner. I already bought a 4228 from Warren Electronics. Does anyone think this antenna will work better for me than the Blake in my situation or am I just going to more trouble for nothing?
 

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Since the RS bowtie did not work at all and the 4248 worked better, this indicates that you are getting a weak signal and/or multipath. Being just 15 miles away with a line of sight, a weak signal probably is not the case. If the multipath is coming from the rear, the 4228 should work ok, but if it's in the front, it may be worse than the 4248. Since you already placed the order, I guess you will find out shortly. I have a 4228 and a 4221 stored in the attic that did not work for me.


Can you actually see the towers from your sight?
 

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Discussion Starter · #7 ·
Glenn,


No, as my house is at the bottom of a hill, I can't see the towers from my location. I have alot of big trees well above the rear of the antenna mount (about 30 feet behind).
 

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Well here is an old bit of news that may help " When the antenna fails make the mast TALLER" my CM 4228 did not work that well till I got it above the trees. I am using a RS 40ft Telescoping mast with another 5ft on that so that its above the tree line. You maybe getting reflections from the trees? or are the trees blocking you?
 

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Quote:
Originally posted by Andrew Sabin
No, as my house is at the bottom of a hill, I can't see the towers from my location. I have alot of big trees well above the rear of the antenna mount (about 30 feet behind).
Andrew,


In your previous posts you stated that you had a line of sight? Since you don't, I have a feeling you are getting scattered signals coming over the hill causing multipath. Multipath tends to be worse the closer you are to the transmitters in this type of situation. I only recommend bowtie antennas when there is a line of sight and the distance is less than 30 miles. I think you may be better off with your first idea of horizontal stacking. But give the 4228 a try, the trees behind you could be causing some problems.


You should also try to place your mast at some different locations on the roof, multipath can change a lot with small changes in location and height.
 
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