Casio Digital Horn DH100
Dorian's DH100 Page
(also works for DH200)
(see end of page for DH500)
These digital horns are little more than toys but what fantastic fun they are!!
Trouble is they all seem to have gone wrong.
When switched on all they do is squeak. If yours is like this then read on.
They can be fixed! (only the squeak problem)
I have two, and when the first broke I just thought that's that, but when the second developed the same fault I started looking on the Internet for a solution. Then I found that hundreds of people have exactly the same problem.
That's when I realized it must be a bad batch of components. Hopefully not a chip because they would be impossible to get now. What a relief to find that it was just a faulty capacitor. I took my second horn to bits and did the same repair and that worked too. I live in England and the cost of the capacitor is approx. 30 pence (50 cents US). Get them from your local Tandy or electrical repair shop. If you are not confident enough to try a repair, print this page and take it to your local repair shop.
Shame that Casio didn't tell us what to do on their website! Anyway, I'm doing it now.
Follow these instructions:-
Remove the mouthpiece, batteries and all the case screws (don't forget the one in the battery compartment).
Once opened you will see two printed circuit boards in a stack, remove the screws from the top board and carefully turn the board over. At one edge of the board you will see the offending capacitor. (C39 which is 33uF)
Very carefully and without damaging the circuit board, either unsolder or cut the capacitor out. I used a very small and sharp pair of cutters to do this. It is also possible to wriggle the capacitor with a small pair of pliers until it breaks free. Then unsolder or cut off any remaining legs. Double check with a magnifying glass if possible to be really sure that you have not left a short circuit here! The capacitor can also leak a corrosive fluid, make sure the circuit board is dry before continuing. A cloth soaked with alcohol will clean it.
Make sure you use the right holes!
Insert a 33uF (or as I did a 47uF tantalum bead ) capacitor in the feed through holes on the board. (see photo)
Any type of capacitor will do as long as its small enough to fit in the the space available. The working voltage should be at least 6V.
Double check the polarity before soldering in place. Trim the excess wire off the legs of the capacitor and that's it!!
Re-assemble your horn and enjoy.
Over 1000 horns have been fixed using these instructions and I thank everyone who wrote to tell me of their success, but sadly I can no longer have my e-mail address on the page because of huge quantities of spam.
Links to other sites:-
Paul Fox has a site with details (and photos) of other fixes and setups. Well worth a visit! http://homepage.ntlworld.com/paul.fox4/casiofixes.htm
DH500 Information.
Several people have told me of their success in fixing DH500s. The basic fault is the same, bad capacitors, but there is more than one in the 500.
The large value capacitors are C11, C37 & C42. I hope this is enough information for you to fix your horn.