Linear amplifier circuit

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ssilva
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Linear amplifier circuit

Post by ssilva » Tue Jan 08, 2002 11:13 pm

I'm in need of a linear amplifier circuit to boost .7 watts to 10-15 watts in the 82.75 mhz range. Anyone know where I can find one?

russlk
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Re: Linear amplifier circuit

Post by russlk » Wed Jan 09, 2002 11:50 am

You only need a linear amplifier for AM, if it is FM any amplifier will do. What is the bandwidth?

ssilva
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Re: Linear amplifier circuit

Post by ssilva » Thu Jan 10, 2002 11:39 pm

I made a mistake in my original posting. The correct frequency is 82 KHz not MHz. The application is for a prototype agricultural machine in which we are using a cable tracer as a sensor for the top wire in a grape vinyard. The problem is we lose signal after a couple hundre feet. Part of the problem I'm sure is the fact we are using the top wire as an antenna, which is unfortunately grounded by the metal grape stakes. Any ideas????? Or other ideas for sensing the wire?

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Chris Smith
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Re: Linear amplifier circuit

Post by Chris Smith » Fri Jan 11, 2002 1:04 am

I use my five miles of barbed wire fence for my night time AM radio reception. INSULATE it from the posts. I get Florida radio stations [and beyond] from my rural California property, clear as a bell! Are you from Clovis/ near by?<p>[ January 11, 2002: Message edited by: Chris Smith ]</p>

Dean Huster
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Re: Linear amplifier circuit

Post by Dean Huster » Fri Jan 11, 2002 9:57 am

Chris, sounds like you've implemented a Beverage antenna with it's length and distance from the ground. I understand they're one of the greatest for AM broadcast band DXing and I have yet to set one up. I shall within the next year.<p>Scott, 87KHz isn't above the upper end of some good audio power amplifiers. Maybe driving an audio output transformer "in reverse" from the amp and feeding the original primary to the wire will get you somewhere. As Chris mentioned, not having that top wire insulated may prove problematic.<p>Dean
Dean Huster, Electronics Curmudgeon
Contributing Editor emeritus, "Q & A", of the former "Poptronics" magazine (formerly "Popular Electronics" and "Electronics Now" magazines).

R.I.P.

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