AIWA HS-JX707 memory battery replacement
plop - 2011-07-02 08:40
As an owner of an AIWA HS-JX707 do you find it a real pain to have to set the clock and tune in all your favorite stations all the time everytime the AAA batteries run down? Well, back in the early 90s AIWA had thought about this problem, and put a tiny little rechargeable battery inside your JX707 to keep those settings safe for 60 minutes whilst you went about swapping in new batteries. Alas over time the battery is but a shadow of what it once was.
However all is not lost if you've now gotten fed up setting the time on the clock for there is a replacement rechargeable available.
The original battery used is a lowly little 3.0V rechargeable Panasonic CL1220. As with most things from 1992, this is no longer available. BOO! The good news is, there's a modern day equivalent. YAY!
I have about a brand new Sanyo ML1220 15mAh battery (part number SY104-ND) however since ordering this, a newer more capacious Panasonic ML1220 17mAh battery has turned up on Digi-Key (part number P663-ND). Both are direct replacements over the CL1220 with more than double the original's capacity of a mere 6mAh.
The memory battery is located in the door of the JX707. To access this, it is necessary to remove the internal metal panel. Remove all the screws and then gently prise the panel from the custom chip. The custom chip controls the logic for all the high level controls and display of the JX707, so if you use too much force at this point you could rip it from the PC board. It is held on with some double sided adhesive.
Note : For some stupid reason AIWA chose to double over the flexible PC board on this model and employ minimal strain reinforcement, therefore you may find that due to normal wear and tear that it is either cracked or would tear very easily. It is highly recommended to pay close attention to the positioning of this cable and to minimise any strain in order to prolong the life of this flexible PC board. Failing to do so, could render your JX707 inoperable.
Once the panel is removed, you can clearly see the custom Toshiba chip in the centre and the memory battery on the top right hand corner.
Remove the two silver screws holding the PC board. At this point it is possible to remove the door from the PC board. Carefully do so, observing that there is some adhesive tape holding the AM aerial ferrite core to the door.
With the door removed, remove the sticky tape which is protecting the battery from short outs.
The reverse side shows the polarity. From this position you should be able to remove the old battery.
Tip : I inserted a cassette into the JX707 to give myself a firm base to work on.
The old battery was removed and it's voltage checked with a voltmeter. It read 0.8V. Wholly inadequate for it's purpose. The replacement Sanyo was put into it's place. You will notice below the clock now has started to work. When the memory battery is discharging the tape reel display also animates.
Now it's just a matter of re-assembly. Having carefully removed the sticky tape from the old battery, I am able to reuse it again.
All done.
I've included the old battery in this picture for anyone wanting to see the original type number (but you may have to zoom into this photo to see it).
This procedure also applies to the other AIWA models in this series namely the JX70, JX707D, JX909, JX929, JX3000, and JX3000D.
Edited to reflect slightly differing termination end of the P294-ND, and instead recommend the P663-ND.
toocool4 - 2011-07-02 11:46
Wow looking at that unit takes me back to when I use to own one, happy days. 
plop - 2011-07-02 12:05
If you get a good example they are the muts nuts and a keeper for sure.
kerni99 - 2011-08-03 05:22
Hello plop,
One question. Do you know, how the memory battery will be charged? Will it be charged by the internal or external battery? Or do I have to attach the power supply to the external battery box to charge it? If the last, do you have an idea, how long it will take to charge the memory battery?
Thanks and best regards
kerni99
plop - 2011-08-03 05:50
I am not entirely sure how long it takes to charge the battery, but it charges whenever there is power applied to the unit.
FYI the new memory battery has lasted for more than one week fully charged without a top up. This is definitely way more than what the original battery was capable of at ~1 hour.
cosmos99 - 2011-10-23 00:11
a newer more capacious Panasonic ML1220 17mAh battery has turned up on Digi-Key (part number P294-ND
Plop, there's something wrong here ,can you check please !
plop - 2011-10-23 01:52
a newer more capacious Panasonic ML1220 17mAh battery has turned up on Digi-Key (part number P294-ND
Plop, there's something wrong here ,can you check please !
You weren't clear with your question of "there's something wrong", so I am going to make a guess.
There are two is one similar batteries now listed by Digi-Key (There was only the one back in July).
P294-ND
P663-ND
Is that your concern? I'd say the newer P663-ND is a better fit out of the two. Or alternatively go with the original SY104-ND which I know definitely fits.
In any case, it is always worth checking with suppliers should they change catalogue codes or make obsolete any parts. Just because it was correct at the time of posting originally does not qualify it to be correct still.
cosmos99 - 2011-10-23 14:44
Oh my ! The site is back ! 
I don't know for you but i had a strange web page since this morning.
Well , dear Plop, this morning while ordering at Digi-key , i couldn't find the panasonic so i ordered a sanyo , the part number you gave leads to a "STATIC SENSOR FIELD METER"... I've also checked in their listing:
http://search.digikey.com/fr/f...LITH%203V%20RECHARGE
there is no P294-ND ! So wether they have changed part number or those are out of stock today.
plop - 2011-10-23 15:38
Here are the direct links to the Panasonic batteries. I am definitely not making this up!
Note they are also alot cheaper than the Sanyo. The P663-ND is the closer match to the Sanyo.
P294-ND
http://parts.digikey.com/1/par...ns-ml-1220-v1an.html
P663-ND
http://parts.digikey.com/1/par...ns-ml-1220-f1bn.html
cosmos99 - 2011-10-23 16:09
I understand now ! If i toggle to USA i can find the panasonic , not "in France" , yet there's no France based Digi-key , you just switch to french language...it seems you also switch parts....
mezenga - 2012-03-13 10:04
As an owner of an AIWA HS-JX707 do you find it a real pain to have to set the clock and tune in all your favorite stations all the time everytime the AAA batteries run down? Well, back in the early 90s AIWA had thought about this problem, and put a tiny little rechargeable battery inside your JX707 to keep those settings safe for 60 minutes whilst you went about swapping in new batteries. Alas over time the battery is but a shadow of what it once was.
However all is not lost if you've now gotten fed up setting the time on the clock for there is a replacement rechargeable available.
The original battery used is a lowly little 3.0V rechargeable Panasonic CL1220. As with most things from 1992, this is no longer available. BOO! The good news is, there's a modern day equivalent. YAY!
I have about a brand new Sanyo ML1220 15mAh battery (part number SY104-ND) however since ordering this, a newer more capacious Panasonic ML1220 17mAh battery has turned up on Digi-Key (part number P663-ND). Both are direct replacements over the CL1220 with more than double the original's capacity of a mere 6mAh.
The memory battery is located in the door of the JX707. To access this, it is necessary to remove the internal metal panel. Remove all the screws and then gently prise the panel from the custom chip. The custom chip controls the logic for all the high level controls and display of the JX707, so if you use too much force at this point you could rip it from the PC board. It is held on with some double sided adhesive.
Note : For some stupid reason AIWA chose to double over the flexible PC board on this model and employ minimal strain reinforcement, therefore you may find that due to normal wear and tear that it is either cracked or would tear very easily. It is highly recommended to pay close attention to the positioning of this cable and to minimise any strain in order to prolong the life of this flexible PC board. Failing to do so, could render your JX707 inoperable.
Once the panel is removed, you can clearly see the custom Toshiba chip in the centre and the memory battery on the top right hand corner.
Remove the two silver screws holding the PC board. At this point it is possible to remove the door from the PC board. Carefully do so, observing that there is some adhesive tape holding the AM aerial ferrite core to the door.
With the door removed, remove the sticky tape which is protecting the battery from short outs.
The reverse side shows the polarity. From this position you should be able to remove the old battery.
Tip : I inserted a cassette into the JX707 to give myself a firm base to work on.
The old battery was removed and it's voltage checked with a voltmeter. It read 0.8V. Wholly inadequate for it's purpose. The replacement Sanyo was put into it's place. You will notice below the clock now has started to work. When the memory battery is discharging the tape reel display also animates.
Now it's just a matter of re-assembly. Having carefully removed the sticky tape from the old battery, I am able to reuse it again.
All done.
I've included the old battery in this picture for anyone wanting to see the original type number (but you may have to zoom into this photo to see it).
This procedure also applies to the other AIWA models in this series namely the JX70, JX707D, JX909, JX929, JX3000, and JX3000D.
Edited to reflect slightly differing termination end of the P294-ND, and instead recommend the P663-ND.
mezenga - 2012-03-13 10:04
Excellent for your help friend!! I have jx707 jx2000 golden, both with the battery problem, here in Brazil not found the ideal battery to replace these Panasonics and Sanyo - you know if the hs-jx810d also has this same setup? Every time I remove the AA battery is the clock to zero and broadcast AM / FM are cleared - have to be adjusted again, a big hug your new friend