MODS THAT YOU HAVE REQUESTED

If you want to change the beep sound to a lower tone, (or fart sound) do this.

The value of the Capacitor is .04, or two .02 mf. ceramic disk capacitors in paralel with indicated diode at the right.

THIS IS A POLARITY PROTECTOR FOR CB RADIO IT IS DESIGNED FOR THOSE OF YOU WHO ARE ALWAYS HOOKING YOUR RADIO UP BACKWARDS AND IT WORKS! I HAVE DONE THIS TO MANY TRUCK DRIVER RADIOS, IT KEEPS THEM FROM BLOWING THINGS UP.

If you want to do this to your radio, here's how.

(1) - Remove covers from radio.
(2) - Find the power socket and remove the 2 wires going to PCBoard at the PCB end.
(3) - The rectifier bridge can be mounted on the rear of the chassis if there is room. Be sure to use heat sink compound.

(4) - If your radio does not have a built-in fuse, you will need to get one, most of the parts can be obtained from Radio Shack, except the zener diode, I don't think they stock that big of a diode.

(5) - That's about it folks, just follow the diagram, when you finish, double check your wiring to make sure everything is just like the drawing.

(6) - Finally, apply power to your radio with normal polarity, then reverse the + and - wires, you should still have power to the radio.

ECHO BOARD INSTALLATION

[1] - This is an 8 to 10 volt Echo Board, hook the Brown wire to 8 to 10 volts, See the note at the bottom of page.

[2] - Hook Black wire to PCB -DC ground.
[3] - Unhook Audio wire from mic socket.
[4] - Put White wire EB J2 to Audio pin of mic socket.
[5] - Hook White wire of J1 to wire removed from mic socket.
[6] - Hook both Shields from J1 & J2 to radio PC Ground.

SECOND WAY TO INSTALL

[1] - Repeat steps 1,2 & 6.
[2] - Tie White wires from J1 & J2 tie together and hook directly to radio mic socket audio pin.

NOTE: 12 Volt hookup will cause echo override and feedback. You must install the diode regulator ( above right) to drop voltage from 12 VDC to 9.1 VDC. By the way, the zener is a 1-3 watt diode.

The resistor is a 100 to 150 ohms and must be rated for at least 2 watts

NOTE 2: VR-1 is the balance control.

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