selective OTA preamplifier

[maria.mirela]

Hi everybody
I'm wondering if somebody solve efficient my problem receiving with the same antenna different strength signals. I live in Thornhill, ON, and channels from CN tower and Buffalo have the same azimuth from my place. If i want to amplify the weaker ones from Buffalo, the strongest from CN tower over loaded the preamplifier and i don't see anything. Theoretically I have to use for each channel a pass band filter and preamplifier and a combiner for all of them but there are to many and is to complicated and expensive. Maybe you have a better idea. Thanks anyway.

[Terryl]

WOW you do have a problem, to solve this one it will get expensive.

One way we use to fix this problem was to get an antenna that was cut just for the problem station(s), and using several antennas we would combine the problem ones 180 degrees out of phase thus they would self attenuate, all this was done before the pre-amps.

In your case you have too many stations to work with, if there was some degree of separation you could use a hi-gain very directional antenna for the distant stations and a low gain for the close in ones, but your distant stations are directly behind the ones that are too close.

I come up with this channel list, I don’t know what channels you want but if you can give me an idea maybe I could come up with something.

Toronto. Buffalo
3, 2
5, 4
9, 7
11, 17
19, 23
25, 25
36, 26
41, 29
47, 40
52, 49
57, 51
69, 56
67

[maria.mirela]

the weaker channel which I want to amplify are
2.1(33), 4.1(39), 7.1(38), 17.1(43), 49.1(49)
Without any preamplifier just with OTA, sometimes, when is good weather, I can see them all ( included all CN tower ones) but most of the time not.

[Terryl]

OK I’ve been studying this and it’s a bugger to solve with out some big expense at your end.

One way to do this would be to put a hi-gain antenna on a mast at about 40 feet off the roof, at a lower height say around 10 to 15 feet a lower gain antenna would be mounted, you would have to run seperate coaxes for each antenna.

The hi-gain antenna would be amplified, the lower one would not, and you would then run two coaxes down to an A/B switch, you use the hi-gain antenna to watch the far away channels, the low gain one for the close in ones.

The only way to watch TV with out the switch is to put channel filters on the hi-gain side to filter out the close in channels and then run the two antennas into a summing amp.
The bad thing with that is the channels filters are not cheap, and you have to amplify before and after the filters.

[maria.mirela]

Thanks for advise. The only question which I have is for the two antenna with the A/B switch. I don't understand haw I be able to amplify the weaker channels if they are received together with strong ones because of the same azimuth and the same antenna. I can do that if I put channel filters for all strong channels or I'm wrong ? Please make me clear about this.

[Terryl]

You can use one hi-gain antenna for the far away stations then use a lower gain antenna for the close in stations, the A/B switch can switch between the two, you can also get an A/B/C switch that way you can use 3 antennas, some of these switches have remotes for them.

[Terryl]

Here is a company that has channel filter and amps that may be able to solve your problems,

http://www.picomacom.com/

What could be done is to setup a hi-gain antenna with the filters to knock out the locals, then a lo-gain antenna for the locals only.

[Tower Guy]

Here is a company that has channel filter and amps that may be able to solve your problems,

http://www.picomacom.com/

What could be done is to setup a hi-gain antenna with the filters to knock out the locals, then a lo-gain antenna for the locals only.

That works, but there's another option that's in Toronto, Tinlee Electronics

[maria.mirela]

thanks, I will try to see if works.

[ridgestar]

maria.mirela,

as a curtesouy we are provided the thanks button. It is a small gesture we all use to show oure gratitude for the help we receive here. Don't be shy, this post hits right on the spot for me as well and the least i can do is hit the thanks button. I would have never gotten to this point on my own.

[maria.mirela]

sorry that I just said Thanks and I didn't pressed Thanks button