Crystal Earpiece Repair




Introduction: Crystal Earpiece Repair

About: I have been in electronics since 1973 I have worked as a TV engineer, Automotive test equipment repairs, Warehouse control systems,Computer and color printer repairs , and have been running a small business...

You can get these crystal earpieces but they are often unreliable or stop working or have low output

they all seem to be made the same they range in price from about £2.50 up to £6

The main cause of failure is the connection to the aluminium diaphram inside which in the original is a piece of iffy copper glued onto the surface of the aluminium, highly suspect ...then that is fed underneath to the rear connection

My fix is to add another connection wire alongside this

see the following steps

I have repaired all 6 of my ones which were in varius stages of not working

one would work fine then just stop, others were low and distorted, one did not function at all

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Step 1: Crystal Earpiece Repair 1

The first thing is to unscrew the clear ear plug and put that to one side

Next about 3 mm down from the front side edge you will see a contruction line where the top piece mounts onto the rear assembly... Put a mark across this to aid when refitting allignment

Taking a sharp knife score VERY CAREFULLY around the whole of the outside of the body


At one point press a little harder to get started enough to get a small sharpened 3mm flat screwdriver in

gently force the plastic apart using the flat blade....once started using the screwdriver blade slightly length ways seems to helps minimise any spliting

if it does start to split go around again with the knife..... the plastic is not very thick and should come apart fairly easily

once apart you should have the top part and the ally diaphram attatched to the rear assmbly as in the photo

notice the old connection tab and where to drill for the new wire ...see next step

Step 2: Crystal Earpiece Repair 2

Next turn the rear assembly over

remove the 1 screw holding the rear wire cover and remove the cover and place to one side

Next drill a small hole in the rear in the place shown in the pic BE CAREFULL not to pierce the diaphram go slowly

The rear cover will hide this later

Step 3: Crystal Earpiece Repair 3

Next You drill a small hole in the side as shown or you can try to prize up the ally diaphram a little to get the wire under

drill the hole to the Left of where the original tab connection is glued when viewed from the top diaphram

and with main audio lead at bottom

see position in photo above

I did the hole method as you could split the allminium if its stuck down too well

see picture

Step 4: Crystal Earpiece Repair 4


get some multistranded copper wire about 2 inches long

Feed that from the rear hole and out through the side hole

IT may help to pre bend the wire slightly to get it to curve out through the hole

see photos

Step 5: Crystal Earpiece Repair 5

Solder one end of the wire to the rear terminal as shown in the picture

Leaving the longest piece coming out from the side

you can refit the rear cover now with the screw

Step 6: Crystal Earpiece Repair 6

You now take the long wire bend it back on itself and you can poke the end just back in the hole again

and leave a loop that can be placed around the edge

(NOTE there was one instance of the poked back wire made contact with the lower diaphram connection.. if you do poke it back then only just in the hole OR maybe instead just lay the wire back on itself along the edge)

this helps make the new connection

see the photo

Step 7: Crystal Earpiece Repair 7 Final

This is what it will look like as per the photo

You can bunch up the wire as you want to ensure a good connection

i did mine as per the photo and have all 6 of my earpieces now working well

Next take the top piece and find your marks and refit it onto the bottom assy

this will squash up the new stranded wires youve fitted and make a much better connection than the original

you can test it at this point before adding the glue to the outside

add a few drops of superglue to the outside re-assy line and press the assy

refit the clear plastic ear plug

and now you will have a working earpiece that will work much better

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    8 Discussions


    1 year ago

    I am woundering if these are the same piezoelectric earphones?

    as The last 2 I purchased were from there and I have not had a problem with them but I have only used them a few times and I am not sure if I should open them up to apply this fix since they are working fine I am afraid to open them up and end up with a issue I didn't have before.


    Reply 1 year ago

    Hi the old saying if it aint broke dont touch it is a good one ...if your not used to taking things apart then i would err on leaving them alone as not all go faulty however the construction does rely on how good a glued connection the originals have and in damp enviroments eventually the copper strip will deteriate under the glue

    i bought 6 non working ones cheap off ebay and got all 6 working fine after my mod


    2 years ago

    I have a question. What if I had grown Rochelle salt crystals, added a piece of copper to one side and then attach a wire to the top of the crystal, then one to the copper plate and placed it, with its copper face, on a window.. would this amplify sound from the crystal radio seen as the fundamental requirements for an earpiece have been met?


    Reply 2 years ago

    Hi Cory
    i have never tried to make an earphone myself I am always fixing things that dont work that others have made so much poorly made stuff nowadays not meant to last or be repaired..As for your question the only way to learn is to go ahead and do it try what youve said experiment even if it did not work what youll learn in the process will add to your knowledge ive built circuits up from the internet that have not worked only to find serious flaws with the designs some would never work there is a lot of poor information out there i found one such duff circuit posted on about 10 different sites so my advice is build it and learn that will make you a better engineer. good luck best regards steve


    3 years ago

    Update 2..... I have found 1 instance where when i tucked the wire back into the hole in the side a couple of strands shorted to the underneath diaphram connection... so make shure the wire end is twisted and dont poke it in too far just in the hole will do could just lay the wire back on itself along the edge and not poke it back into the hole its up to you as you cant see inside unless you lift the ally diaphram


    3 years ago

    Update... out of the 18 units I have done so far this way only one did not come apart easily the top part did split after 20 mins careful prizeing usually takes about 5 mins .. On thurther investigation i found it had 2 diaphrams units fitted one on top of the other and so it must have been hard to fit together which may answer why it was glued together so well


    3 years ago

    Hope it helps others and stops them being thrown away


    3 years ago

    I'm glad you could fix it!