1955 Manuals

Cobra HG M75

Manuals and User Guides for Cobra HG M75. We found 2 manuals for free downloads Manual, User manual

The Cobra HG M75 is a 4-pin power CB microphone with a 9 foot high-flex cord, heavy-duty ABS shell, metal mesh grille, left-side PTT button, and a powered 2 transistor amplifier with gain control. This document provides instructions for upgrading the audio output of the Cobra HG M75 microphone to match or exceed other power mics on the market, without distortion.

Key Features

9 ft high-flex cord
Heavy-duty drop-proof ABS shell
Metal mesh grille
Left-side PTT button
Powered 2 transistor amp with gain control

Cobra HG M75 CB Microphone Upgrade Instructions

Pages: 7 Cobra HG M75 Manual

Brand: Cobra Category: Motor vehicle electronics Size: 293 KB

Languages: English

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Frequently Answers and Questions

Why is the audio from the HG M75 so low?

The author of this instructions document explains that the HG M75 has a lower audio output than the older 5-pin power mic CA71B, even though it uses a 9V battery compared to the CA71B's 6V battery. The low audio is likely due to the design of the HG M75's amplifier circuit.

What is the purpose of the modifications in this document?

The instructions describe a way to boost the audio output of the HG M75 by changing the values of some resistors and capacitors in the amplifier circuit. The author states that these modifications can increase the audio output by up to 40dB, which should be a significant improvement.

How do I perform the modifications to the HG M75?

First, you need to open the microphone and unscrew the microphone element from the amplifier board. The document instructs you to remove a 1K resistor (R6), remove a 1.8K resistor (R7) and install a 220 ohm resistor in its place, and change a capacitor (C1) to 0.47uF. Finally, you should test the microphone and close it up.