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[marineau]

Expert,

What is your opinion about install an amplifier on external antenna on CM15A ?

If I Install this LSA151, is it a good idea ?
Does strong signals above 310MHz that could overload the preamp. ?

Here a specifications about this LSA151:
http://www.lindsaybroadbandinc.com/product.line/amplifiers/sub.amps/pdf/Advanced_Services_Subscriber_Amplifier.pdf

Does anyone tried this or another amplifier ?
Do you have a suggestion ?

[dave w]

FWIW department,

Can't help you with the LSA 15, but I tried a standard TV amp, similar to this one from Crutchfield:

http://www.crutchfield.com/S-gSU7Y1wy2kY/cgi-bin/prodview.asp?i=6593042

It did not seem to make much difference.

Since it is broad band with no filtering, it probably increased noise detrimentally.

[marineau]

It did not seem to make much difference.

Does you are sure that your module can work to 310Mhz ?
How much Db do you have tested ?


Thanks

[Puck]

Just to add some technical info to the topic:

Looking at the CM15A's receiver IC datasheet, the typical sensitivity of the receiver is -98dBm and the typical maximum input power is -35dBm.

From the measurements with a spectrum analyzer I have take for the PalmPad (in Re: Disarming DS7000 remotely?) the signal I measured with it situated directly beside a non-tuned (somewhat crude) antenna, was a -28dBm signal.

Normally the remotes (or other RF transmitters) will not be that close to the antenna, so the received signal will be under the -35dBm typical maximum level. But a 15dB amplifier could push it over the receiver's limit and cause reception problems. So basically, an amplifer will help distant signals, but any strong signal close to the receiver can cause problems.

So if you are going to try an amplifier, I suggest having some attenuators on hand and look for a happy medium from all your rf transmitters to the antenna. Also, you should use a 50-Ohm wideband signal amplifier instead of a 75-Ohm CATV amplifier. They cost a bit more, but if you are going to this length to create an uber-reliable system, why cut a corner here?