Microphone Amp

[kj7gs]

I'm looking for a way to make my voice use more than 25% of the power capability of the radio. Even with a speech processor, the radio puts out only half of its power. I'm not one to yell out everything or "eat the mike", but I would like to know if there's a kit out there that I can build to add a little "umph" into it. Any sites/suggestions out there?



-- Don


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[b1kshad0w]

Sounds like something with the radio, what kind is it?


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[kj7gs]

I'm using a Yaesu 767GX, and the speech processor does help, but I don't want to be clipping the audio. The mike is a Radio Shack PA mike. Better sounding than the stock mike, but seems to be down a bit on the power meter. I saw some kits available but don't know what to buy in order to boost things up (don't want to ruin the radio either if it's not designed for it).

-- Don


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[b1kshad0w]

Don't know to be honest. My only guess is an impedance mismatch from using a PA microphone. How does it compare to the stock microphone. Do you have any radio specific microphones to try? I am going to give you a link. It is about the last D104 models in the case, but it talks about this history of microphone and impedance. I am copy/pasting a small part that might help. Like I said, I don't know any am just taking a stab at it so don't make fun of me.

This is from cbworldinformer.com/20011..._story.htm

Before long, the transistorized CB made the scene. These radios for the most part required low impedance microphones. The non-amplified D-104 with either the crystal or ceramic cartridge are high impedance mics and won't work with a low impedance radio. To accommodate the newer radios Astatic came out with the preamplifier kit that could be retrofitted to any existing D-104. Later they manufactured two types of D-104s, one amplified and one not. The amplified version was designed primarily with impedance matching in mind, although it had substantial output gain over the non-amplified unit. This kept them in the CB market as the tube radios were quickly disappearing, while keeping the Astatic signature sound in the CB market for more generations.


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[kj7gs]

I'm sure the impedance is good, I followed the instruction manual for the radio and that part of it is fine. What worries me is putting watts/voltage/whatever into the TX Audio pin. I'd like to keep the radio and all of its circuitry, it's gotta last me a while!



-- Don


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