Bluetooth headset

[Harry Bloomfield]

I didn't really expect much at the price and I wasn't disappointed - A cheap ebay Chinese pair of earphones, mic and rechargeable, with mic, battery, plus control buttons nearer one earphone than the other and suggested to be stereo. Just earphone - wire - control - earphone.The first set to arrive was dead, no voltage across the Li-po at all. I complained to the seller and another replacement arrived today. This set works, but the earphone which is furthest from the control is almost silent - call that the 'left one'.

Looking into the 'sound hole' of the right one, it has a plastic tri-point close to the face of the sound hole. The faulty left one lacks this bit of plastic and I can see something like it at the bottom of the hole, by the diaphragm - Oh thought I, the bit of plastic has been broken inside and is restricting the movement of the diaphragm making it quiet. Then I looked at the first completely dead example and it is the same.

I had it in mind to either swap batteies between the two, or earphones - to try to make up one fully operational example out of the two. Does the 'tri-point' plastic bit maybe mark the left and right earphone?

 

[Harry Bloomfield]

Update fixed it - one good unit out of two and to be fair, it sounds pretty good for the few pennies it cost. I still don't know which is supposed to be which channel, or why the the two earphones appear to be slightly different down the hole?

I first tried swapping the known good battery from the second unit to the first unit. That got the first unit all working, so I decided to reassemble that one, something went amiss and midway through reassembly it refused to turn on again. Rather investigate it further - this is micro soldering - I tried swapping the known good left lead + earphone to the second unit. That worked properly, so I tried reassembling that one and retesting - all working.