VR 1 - 50K

TR 1 - BC549

OR SUBSTITUTE EITHER OF THESE:

2N5818, 2N4401

R1=470K----R2=4.7K----R3=4.7K----R4=220K----R5=4.7K----R6=220 Ohm

C1=0.01Uf Ceramic (103) ---C2=0.0047 Uf Ceramic (472) ---C3=0.0047 Uf Ceramic (472)

C4=220 Uf 16 Volt Elect. cap (this capacitor controls the duration of the bleep and may need to be a different value because the type of relay used may need more current.)

The two diodes are of the 4148/914 silicon type

The relay is a SPDT 12 Volt miniature type

When the switch wire is connected to +12 VDC the bleep is enabled (will sound when you de-key), when the wire is not connected the bleep is disabled (will not sound when you de-key).

TX OUT--------TX wire that was removed from the mike socket.

RX OUT--------RX wire that was removed from the mike socket.

AUDIO OUT---Attach to audio wire on the mike socket.

TX IN-----------Attach to the TX pin on the mike socket.

SWITCH--------Wire as shown in the above picture.

+ 12 VDC-------Attach to the constant + 12 V supply on the radio's on/off switch
(make sure you take it after the switch, otherwise the bleep will be powered up even when the set is OFF !)

EARTH---------Attach to the Earth/Ground/-0 Vdc.