Monday, July 04, 2011

Replacing and Relocating The Battery In A Kenwood TM-331 (TM-241, TM-441, Etc.


No write-up yet…  just pictures.

Will type up notes over the next few days.

- Steve, W4HKL


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Here’s a look at what’s needed to perform the battery swap and relocation.

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The most important component for protracted work of any kind.

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The Kenwood TM-330 220 Mhz rig.

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The following 4 screws need to be removed.

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Flip it over and remove the 4 on the bottom cover.

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I’m pointing to the areas you need to gently tug on to remove the covers.

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Once you get it tilted up you can pull it free. Note the tabs.  You will have to do this process in reverse at the end of the batter swap/replace.

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Flipping it back to repeat the process on top.

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The top removed.

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I’m glad someone on the design team designed a nice, long speaker wire.


Remove the battery mount.

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This is the connector for the optional CTCSS decoder.  Note how it is routed into the faceplate area as the battery lead will be placed beside it.

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Now the hard part.  Once the knobs are pulled loose you will have to CAREFULLY lift these up and gently slide the black plastic faceplate cover off.

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Did I mention they’re brittle and extremely annoying as they have a nasty habit of snapping back on as you try to slide the next one off?

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Poweraid caps make a nice place to store various parts.

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Little buggers…

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This part took about 10 minutes.

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Keep working it back and forth until its off.

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We need to remove this part of the faceplate to get to the battery.  Be careful of the buttons.  I was lucky with this radio.  I screwed up with a TM-731 and allowed all the buttons to fall of.  Imagine spilling a box of chicklets onto your desk and carpet – several times.

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Fortunately the retaining nut on the mic plug was removable with these forceps.

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And the other nut…

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Easy does it…

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But wait, there’s more!!!

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Remove the metal covering…  6 or so screws spread around the top, bottom, and sides.

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Okay, this it it the brains of the unit.  Use an anti-static wrist strap… or just make sure you touch something grounded every so often as a precaution.

On a positive note, the TM-241, 441, etc, are a LOT easier to get into than this.  In fact, after doing the 241 and 441, I kept thinking “what’s next” with the 331.

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3 screws need to be removed.  They are pointed out here.

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The last step to removing the CPU board is sliding it off the connectors pointed out here.  You have to be careful.  It won’t just slide loose.  Use your fingers and work each side back and forth until you see the gap form between the two sides of the connectors.

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There is goes…

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Note that only the ends of this board are supported when placed like this.  Be careful not to press down hard in the middle and flex the circuit board. 


Continued in Part II…

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