<p><a href="https://www.youtube.com/watch?v=kPZbXyUNxCw">Link to the
YouTube video I used that described the process of removing the two
backup batteries in a Kenwood TS-940S.</a></p>
<p><a href="https://en.wikipedia.org/wiki/Phase-locked_loop">I mention
the acronym PLL which stands for Phase Locked Loop. Here is a Wikipedia
article about PLL.</a></p>
<p><strong>Picture 1</strong><br />
<img src="https://hackerpublicradio.org/eps/hpr4212/hpr4212/1.jpeg"
alt="Picture 1 shows a top down view of the radio. The large black square section located at the front left of the picture contains the speaker left and control board right. With the top cover fitted the control board is accessible via s sliding cover. Both the speaker and control board need to be removed in order to get access to the PLL backup battery. Both come out as one piece." /><br />
shows a top down view of the radio. The large black square section
located at the front left of the picture contains the speaker left and
control board right. With the top cover fitted the control board is
accessible via s sliding cover. Both the speaker and control board need
to be removed in order to get access to the PLL backup battery. Both
come out as one piece.</p>
<p><strong>Picture 2</strong><br />
<img src="https://hackerpublicradio.org/eps/hpr4212/hpr4212/2.jpeg"
alt="Picture 2 shows the first three connectors that need removing from the control board. All six connectors need removing before lifting the control board and speaker." /><br />
shows the first three connectors that need removing from the control
board. All six connectors need removing before lifting the control board
and speaker.</p>
<p><strong>Picture 3</strong><br />
<img src="https://hackerpublicradio.org/eps/hpr4212/hpr4212/3.jpeg"
alt="Picture 3 shows the second three connectors that need removing from the control board. Notice they are marked with the letter F." /><br />
shows the second three connectors that need removing from the control
board. Notice they are marked with the letter F.</p>
<p><strong>Picture 4</strong><br />
<img src="https://hackerpublicradio.org/eps/hpr4212/hpr4212/4.jpeg"
alt="Picture 4 shows one of the connectors removed. I was nervous removing these. Fortunately I was able to remove them without causing any damage." /><br />
shows one of the connectors removed. I was nervous removing these.
Fortunately I was able to remove them without causing any damage.</p>
<p><a href="http://www.aeroelectric.com/articles/pigtail/pigtail3.jpg">I
mention the terms pigtail and screened cables. Here is a link to a
pigtail soldered to a screened cable.</a></p>
<p><strong>Picture 5</strong><br />
<img src="https://hackerpublicradio.org/eps/hpr4212/hpr4212/5.jpeg"
alt="Picture 5 shows the speaker and control board lifted out of place and swiveled to the side to reveal the PLL unit which is encased in a metal box for screening. There are eight screws on the top lid that need removing to gain access to the inside of the screened PLL unit." /><br />
shows the speaker and control board lifted out of place and swiveled to
the side to reveal the PLL unit which is encased in a metal box for
screening. There are eight screws on the top lid that need removing to
gain access to the inside of the screened PLL unit.</p>
<p><strong>Picture 6</strong><br />
<img src="https://hackerpublicradio.org/eps/hpr4212/hpr4212/6.jpeg"
alt="Picture 6 shows the top cover removed from the screened PLL unit revealing the backup battery located in the middle of the picture (Silver disc with orange outer rim). The top cover is swiveled to the left hand side out of the way." /><br />
shows the top cover removed from the screened PLL unit revealing the
backup battery located in the middle of the picture (Silver disc with
orange outer rim). The top cover is swiveled to the left hand side out
of the way.</p>
<p><strong>Picture 7</strong><br />
<img src="https://hackerpublicradio.org/eps/hpr4212/hpr4212/7.jpeg"
alt="Picture 7 shows a close up of the PLL backup battery. From the picture droplets of liquid can clearly be seen on the right hand connecting terminal indicating that the battery is leaking and must be removed before damage occurs. On the right hand side of the picture notice the two connectors attached to the circuit board that are terminated with unused sockets. I have no idea what these sockets are used for. There are brass pillars either side of the connectors. I assume some sort of add on board could be purchased and perhaps this was what the unused connectors are for. I also mention an unpopulated IC socket that can be seen in the top left hand side of the picture. This is probably for another optional extra." /><br />
shows a close up of the PLL backup battery. From the picture droplets of
liquid can clearly be seen on the right hand connecting terminal
indicating that the battery is leaking and must be removed before damage
occurs. On the right hand side of the picture notice the two connectors
attached to the circuit board that are terminated with unused sockets. I
have no idea what these sockets are used for. There are brass pillars
either side of the connectors. I assume some sort of add on board could
be purchased and perhaps this is what the unused connectors are for. I
also mention an unpopulated IC socket that can be seen in the top left
hand side of the picture. This is probably for another optional
extra.</p>
