View Full Version : Using Pre-amp with stations close by


Larry Kenney
05-19-08, 05:03 AM
I'm wondering if a pre-amp, such as the CM 7777, is feasible for bringing in the distant stations when you're located close to some local stations?

I live 3/4 of a mile from Sutro Tower in San Francisco but need help receiving most of the Sacramento stations. Using a CM 4228 I can always get KMAX 21 (31) and I get KTXL 55 (40) most of the time, but the other stations are all below the required Signal-to-noise ratio to be received, some by a dB or two, some three or four dB.

Will the local stations over power the pre-amp making it useless for the distant stations or will the pre-amp work well enough to make a difference so that those weaker signals will come in?

Thanks for your thoughts and ideas.

Larry
SF

Tower Guy
05-19-08, 06:09 AM
I'm wondering if a pre-amp, such as the CM 7777, is feasible for bringing in the distant stations when you're located close to some local stations?

I live 3/4 of a mile from Sutro Tower in San Francisco but need help receiving most of the Sacramento stations.

Your only hope to for reception from Sacramento is the use of channel filters. The SF stations may overload your tuner even without a preamp. It's possible that filters alone may be enough. If a filter removes enough of the strong local stations, then a preamp may be useful, but not the high gain 7777.

Falcon_77
05-19-08, 10:49 AM
Unfortunately, I don't see any pre-amps holding up to the signal strengths of Sutro Tower at your location.

To have any realistic chance of using a pre-amp for this purpose, you would probably have to have a custom-made notch filter, covering each Sacramento channel you want to receive. e.g. band-pass for KCRA 35 & KOVR 25, etc. (or whatever channels you want), with all other channels filtered by ~50dB. However, such a filter will be expensive.

Without a notch filter, it will be like looking for stars close to the sun, with a telescope (using a pre-amp).

Tower Guy
05-19-08, 12:00 PM
Thanks for your thoughts and ideas.

You could wait until 2009 and see if the analog stations from Sutro are causing your reception problems.

nybbler
05-19-08, 05:34 PM
Huge grounded metal wall shielding your antenna from Sutro? :-)

Larry Kenney
05-19-08, 09:25 PM
Thanks for the comments. It's like I figured... it's pretty much hopeless with the stations so close to me. I guess I'll take Tower Guy's suggestion and wait until next February and then see what I get.

Larry
SF