995: Coinstar

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Plus they take like 9%.
Title text: Plus they take like 9%.


This is another one of Randall's Tips, this time a Holiday Tip.

Chocolate coins are a popular holiday candy, and thus this is another Christmas comic. These candies are usually plain chocolate formed in the shape of coins and covered in metallic foil wrappers.

Coinstar machines accept all your loose coins, sort them, count them, and then give you the same amount of money in paper currency, around 9% less as it says in the title text. You may find similar machines in grocery stores and shopping malls around the US and Canada.

These machines work by vibrating a box with a series of slots along one side, which each corresponding to the sizes of standard accepted coins. The vibrations move the coins along the different slots. If they pass through the slots the coins are then fed into a mechanism with a counterweight that's balanced to test the weight to ensure that it has captured the appropriate coin. Coins of the right size but wrong weight (such as similarly sized coins of different currencies) are dropped back out into a reject chute to be retrieved by the customer. Coins that do not fit the standard sizes also get rejected in the same way. There are also various anti-theft mechanisms that prevent coins from being counted and then retrieved. Coins that meet the programmed criteria are funneled into internal repositories and are counted towards the total.

The chocolate coins in the comic appear to have damaged the machine. As the only property that the candies share with actual currency may be its appearance the machine would not be designed to handle the softer material causing the machine to malfunction and create the unusual noises presented. The chocolate may have fouled the initial vibrating tabulator; it may be that the coins are getting caught in the reject chute or are fouling the scales. In any case, an alarm has sounded, likely triggered by an electronic circuit going "pop". The alarm could also be the anti-theft system being triggered, thus causing the machine to shut down and preventing false totals from registering.

The title text suggests that the machine would take its customary 9% from the total of the chocolate coins which is ironic since the reader knows that their candy has insignificant monetary value.


[A mischievous Cueball empties a small bag into a machine.]
[Machine makes progressively less happy noises.]
[Machine malfunctions and shuts down.]
[Text below frame]
Holiday tip: Coinstar does not handle chocolate coins well.

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YTo me as electrical engineer it's a lesson that no technology is perfect, but we are working on it. Chocolate coin proof coin-star machines are just around the corner. - e-inspired 15:36, 27 February 2013 (UTC)

That's a special contribution from an expert with no sense of direction. I used Google News BEFORE it was clickbait (talk) 06:59, 22 January 2015 (UTC)

Candies do have monetary value. You buy them. 09:25, 22 May 2014 (UTC)

Could enough coins be exchaged for a bunny? (talk) (please sign your comments with ~~~~)

Yes, if you melted them and poured the melted chocolate into a mold...

Has anyone actually tested whether chocolate coins will break Coinstar machines? I'll try it when I'm an adult. (talk) (please sign your comments with ~~~~)

I had the feeling that the machine opened and ate the chocolate coin ... (talk) (please sign your comments with ~~~~)

To be fair, Coinstar doesn't do so hot with regular coins- though that has more to do with the habits of the coin owners. 14:13, 15 September 2019 (UTC)

Moderatly certain this had nothing to do with any anti-theft system, just a standard error beep that pretty much all machines with hardware for beep codes give. One long beep being the typical obvious error message, that doesn't tell you crap about what the actual error is (might be followed up with a beep code). Unless coinstar machines give just one loud long beep if you trigger the anti-theft mechanism.