.
MID BLOCKING INSTRUCTIONS
For this task you will need to get hold of a TC9106 PLL Chip either new or
from a sourced second hand radio such as the President AR-7.  I
recommend removing the original TC9119 PLL chip in your Audioline or
Uniden radio as the 9106 needs "piggy backing" on top of it and if it is still
in the radio it is difficult to solder the legs without blobbing or burning
something you shouldn't.

Step 1/ Take your TC9106 PLL chip and either cut off pins 3,4,6 and 7 or
bend them up underneath the body of the PLL chip as these are not used.

Step 2/ Position the 9106 in line on top of the 9119 making sure the indent
cut outs are at the same end on each. Then solder pins 10 to 18 together.
Turn the PLL chip around and solder pins 1,2 and 8 together. Lift pin 9 of
the 9106 so it goes on top of itself also pin 5.  Your PLL's should look like
the diagrams on the right now.

Step 3/ Solder a 103 cap between pin 9 of the 9106 and pin 9 of the 9119.

Step 4/ Re-solder the PLL's back in to the CB radio making sure correct
polarity is observed.

Step 5/ On the track side of the PLL wiring on the main board cut the track
from pin 5 so it is open circuit. Now, from pin 5 that  you just isolated solder
a piece of wire which will go to a switch of your choosing. Make sure it is
long enough to reach easily. We will call this the UK wire.

Step 6/ Solder a piece of wire from pin 5 of the 9106 PLL which will go to
the same switch as the other wire. We will call this the MID wire

Step 7/ Solder a piece of wire from the other side of the cut track on the
main board. This will also go to the switch and will be called the COMMON.

Step 8/ The common will solder to the middle pin on your switch, the UK
and MID will solder either side of this.

That should conclude the wiring of the mid block. You may need to slightly
tune the radio to the new band or it may work fine straight off. You will need
to check TX and RX on channel 1 MID and 40 UK and if astray make slight
adjustments to the VCO using a plastic trimming tool until all is well. You
may wish to use a switch with two lots of contacts so you can switch in a
small capacitor to drop the frequency slightly when switched to MID.
(Without this your frequency could be up to 1KC out... not a major problem
on FM but something to think about) Without the capacitor I set the UK
frequency a little low so when on MID it is closer to the correct frequency.
Enlarge
Enlarge
/
.
CB Radio Repairers in the UK
CB Radio History from its early days
.