Statement of Empiricism
I have used this heating pad for several years now (I wrote these instructions in December 2007, it's now February 2011).  I have had exactly ZERO issues with it - it works perfectly and the hedgehog is fat and happy.  YOUR MILEAGE MAY VARY!  PLEASE USE EXTREME CAUTION IF YOU FOLLOW THESE STEPS.  If you do this, closely observe the pad for at least a few days to make sure it's not overheating or catching on fire.  See the obnoxious red text below:


So, I got this heating pad at the store a while back to use as a hedgehog heating pad. I found out that the 2-hour auto-off timer was hardcoded into the circuit, and they didnt even bother to put a switch on the casing to disable it. Typical overprotection of the consumer - this wouldnt exist if our country was a bit less litigious.

African hedgehogs need at least 72F to be happy, so a heating pad under the cage is recommended. I mean, how could you say no to his face?

So, to disable it, I decided to take it apart and find the culprit like this guy did. Its too bad that for some reason they decided to make it even harder to change this feature.

Step 1: Surveying The Situation

Here, we can see the circuit board and outer casing.  It’s an Eagle LOPP4, and apparently it was made on Christmas of 2006 (2006-12-25)! It also bears a marking of 07.28, and I have no idea what that means.
<p>These instructions are great. I use it for my Italian greyhound puppy. I also have an LOPP4 NEW board. Soldering on those little pins is tricky, but doable and for the security screws I used an old broken flat head to get a bite on em.</p><p>Thanks for the help!</p>
<p>HI. I have a LOPP4 NEW board on mine. (I also need it for my animals.) It looks a bit different than yours, but not much. The case says EA SAL104. Made in China, of course. Does anyone know which pin on this one I should cut? Thanks so much! I want to jailbreak my hot pad. I'm so high tech! I've attached a picture of mine.</p>
<p>The picture is really hard to read - cell phone? I can see that there's some writing on that chip in the middle. Can you reply with what that says? Use a magnifying glass if necessary.</p>
I have SLA103 on my case. <br>The chip reads:<br>HEF4060BT<br> L2A7DO2<br> UnG12155<br><br>Sideways there's an &quot;o&quot; and possibly &quot;NXP&quot;.
<p>The datasheet is here: </p><p><a href="http://www.nxp.com/products/logic/counters_frequency_dividers/divider_counters/HEF4060BT.html" rel="nofollow">http://www.nxp.com/products/logic/counters_frequen...</a></p><p>It's another 14-stage ripple counter like the CD4060 documented above. On the CD4060, the solution was to wire in a 10K resistor between the MR and VDD pins - see the diagram above. On your chip, these pins are also pins 16 and 12, just like the CD4060, so it looks like this HEF4060 is a drop-in replacement. You can find these resistors online or at your local electronics store. Good luck! (DISCLAIMER: I take no responsibility for any suggestions here - perform modifications at your own risk).</p>
<p>Thanks. I have a similar pad from Walgreens. I put it inside my beehive for the winter and discovered the auto-off problem when outside temps reached the lower teens. </p>
<p>I modded a slightly different Sunbeam heating pad. My circuit board looked different, and the microcontroller was a HEF4060BF (Phillips/NXP). <br> The chip was the same and had the same pinout. On my board, there was a <br> capacitor between pins 13 and 16. I replaced it with a 10K Ohm <br>resistor. <br><br>Images can be seen at: http://jimlund.org/blog/?p=348.</p>
<p>perfect info, just what I needed to sprout my seeds right.</p>
Thanks! Now my hedgehog will stay warm all the time. Hard to find one without an auto off for not much money. Thanks again!
That's a nice and simple mod! And, now I want another hedgehog! :)
Very nice! Is this safe? Will the heating pad heat up long enough to catch fire and cook your hedgehog?
It's on low all the time, and it doesn't get too hot. Again, like the introduction says, I've used it for 3 years with no issues. Cheers.

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Bio: Just a dude who reads a lot of Instructables.
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