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tony2tall
8-May-2016, 7:15 PM
http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d513445fd173b76

What do I need to combine 2 - CM-4228HD antennas mounted in attic?

My intentions are to point one @ 140 degrees ( Memphis stations)

2nd antenna pointing @ 260 degrees (Jonesboro stations).


Do I need a FM trap?

Currently KTEJ - Ch20 signal 85-90% (antenna pointing 260 degrees)

Signal fluctuates even during the best of weather conditions. In

that direction is also a strong FM radio tower.

This novice appreciates your help ��

ADTech
8-May-2016, 9:31 PM
CM-4228HD

Probably an unfortunate choice. Memphis requires an all-channel antenna, Jonesboro requires a 7-51 antenna. The 4228 is neither.

Do I need a FM trap? You haven't told us anything about your existing system, so we don't know how susceptible it might be to FMI. You can always try one and see, they're fairly inexpensive.

tony2tall
8-May-2016, 10:33 PM
Probably an unfortunate choice. Memphis requires an all-channel antenna, Jonesboro requires a 7-51 antenna. The 4228 is neither.

You haven't told us anything about your existing system, so we don't know how susceptible it might be to FMI. You can always try one and see, they're fairly inexpensive.

My attic doesn't offer enough horizontal room to use a deep fringe UHF/VHF antenna. 4228 fits the bill for vertical clearance. Would like to use an outdoor all channel antenna but will require erecting a tower. My house doesn't have a gamble style roof to secure a vertical pole and roof is to steep for roof mounting.

I haven't been able to find a FM trap online. Several years ago at another residence I had an amplifier that included an internal switchable FM filter.

Would grounding an attic mounted antenna reduce signal fluctuations?

ADTech
9-May-2016, 2:21 AM
We have FM traps for sale on our website as an accessory.

Grounding an attic antenna is unlikely to make any difference in your reception.

The physics of the local signals dictates the correct choice of receiving antennas. Basing your decision on anything else will have consequences that you may not be aware of.