Help with CM 7777 amp

[mikenewy]

I am getting a CM 7777 for a roof antenna. Is it ok to hook it up in the switch box vs climbing on the roof. The box is directly below the antenna, about 25 feet of cable. Switch box allows me to connect to the desired tv's and avoids falling on my a--.

 

[gdarwin]

The idea is to get the amp as close to the antenna to keep from amplifing noise picked up by the coax. It might work.

 

[Rick0725]

it is best to mount the preamp as close to the antenna as possible.

I mount preamps where they work best... at the antenna, at the grounding block outdoors or inside at the distribution point.

if you live in the boonies, mast mounting close to the antenna is best. with high gain preamps with short coax runs and living in the suburbs, it sometimes helps to mount the amp farther away from the antenna to tame the signal levels going into the amp lessening the likelyhood of overload...basically used as a distribution amp so to speak.

if the results are not satisfactory with the amp at the distribution point then install at the antenna.

 

[snaggerbob]

I agree with Rick0725, put it low and see how it performs. Mine is about 2ft from the antenna and that works for me. I'm about 30 miles from the towers.

 

[mikenewy]

Thanks guys, I'll try it at the distribution point, check the results, and go from there.

 

[mikenewy]

I hooked the CM 7777 at the Distribution point, directions said to put the power source at the tv, so I did that also. Split the signal after the power supply and sent it 100 feet to the second tv. Close stations about 9 miles away improved to the 70's to the high 80's (811 receiver scale). One station 70 miles away came in with a week signal in the 60's. I aimed the antenna at that one with no improvement for the distant stations. Next I should try the amp close to the antenna. Is the power supply in the right place? Where is it best to split the signal? Thanks, Mike

 

[Jim5506]

There should be no splices or splitters between the power injector and the pre-amp.

 

[mikenewy]

The stations that are 64 miles away are showing sig of 49 on the 811, occasionally they jump to the 60's but the receiver bums out and does a reboot. Is this a bad receiver? Preamp (CM 7777) is still at the distribution point. Close stations come in fine with 80's. Antenna is rated yellow, green, light green and red. Thanks for the help.

 

[gdarwin]

The bounce in signal is multipath problems. Dish receivers will not handle multipath and will reboot when it happens.

 

[mikenewy]

Thanks, I'll try a voom receiver and see if it handles it.

 

[sunelec]

I have an ota setup for my locals going to two 811 receivers and one 921 receiver. I get ota signal levels of 90 to 100 on the 921 with great reception but only 65 to 75 on the 811 and trouble getting some channels. As a test I hooked the same antenna lead to all three receivers one at a time and found out that both 811 receivers perform the same way with a much weaker signal strength. When I talked to Dish technical help I was told that the 811 was weak when processing ota compared to some of their other receivers.

 

[mikenewy]

Thanks Sunelec, that gives me more ammo to get an upgrade to the VIP series with DVR.

 

[sunelec]

Thats the my plan too. I want to upgrade the two 811 's right out of my system. I'm just waiting until after Feb. 1 when Dish starts their new upgrade program.