Jump to content

How Do I Replace Piezo Buzzer

boblalux

By boblalux
in Watch Repairs Help & Advice

 Share

Recommended Posts

boblalux Watch Enthusiast

boblalux

Posted
Posted

How do I replace piezo buzzer
My Timex Expedition has an alarm and hourly chime/buzzer.  It is sometimes weak, sometimes strong, spometimes does not work.  It's possible that I damaged it when writing the battery change date on it!!!
I have a couple of spares and so wish to know....
How to attach?  To get a good electrical contact, I presume I should clean out the old piezo, press the new one in the same position, at the same time putting a 'ring' of heated shellac around the rim of the piezo??
I understand, that before fitting the new buzzer, I can test it by connecting it to an AC source such as the output leads from  an earphone, and turning up the volume control (?)
Thanks in advance for your help.

post-834-0-00406400-1446903395_thumb.jpg

boblalux Watch Enthusiast

boblalux

Posted
  • Author
Posted

Sorry, the spelling slipped: "

Thanks, a Timex site new to me, Unfortunately, my 2x Timexes were manufactured in 2007 and 1999 resp.  I've found infos/catalogues etc for dates before, and after these dates!!! "

JohnR725 Distinguished Member

JohnR725

Posted
Posted

Do you have replacement disc? I doubt writing on it would've damaged the disc unless you pushed really really hard. In order to work it has to have two solid contacts Electrical contacts. So the contacts are on both sides of the disc the side pressing against the back is epoxied On this is a conductive epoxy for electricity. It has to make good physical contact the back serves as the speaker otherwise you're not going to hear very much at all unless is bonded tightly. The other contact the front side is usually a little Gold spring which falls out when the batteries changed. I can't quite see one in the picture? So if you're not making good contact with the disc worst-case no sound poor sound so you have to make good contact. Then whatever's making contact with the silver part of the disc if it makes too much contact you'll scratch the silver off that's a problem also.

 

Replacement involves you getting a new disk if you can and conductive epoxy. I would tend to say it's impossible, except there's a seller on eBay right now selling discs for exactly this. Perhaps if you ask nicely they will tell you how you're supposed to do it. More interesting though is one of the discs is for Seiko in a Seiko package. So if Seiko sold replacement discs there would've been a way to change it and that would be in one of their manuals if we knew the part number and the watch it's supposed to go in.

boblalux Watch Enthusiast

boblalux

Posted
  • Author
Posted (edited)

Do you have replacement disc? I doubt writing on it would've damaged the disc unless you pushed really really hard. In order to work it has to have two solid contacts Electrical contacts. So the contacts are on both sides of the disc the side pressing against the back is epoxied On this is a conductive epoxy for electricity. It has to make good physical contact the back serves as the speaker otherwise you're not going to hear very much at all unless is bonded tightly. The other contact the front side is usually a little Gold spring which falls out when the batteries changed. I can't quite see one in the picture? So if you're not making good contact with the disc worst-case no sound poor sound so you have to make good contact. Then whatever's making contact with the silver part of the disc if it makes too much contact you'll scratch the silver off that's a problem also.

 

Replacement involves you getting a new disk if you can and conductive epoxy. I would tend to say it's impossible, except there's a seller on eBay right now selling discs for exactly this. Perhaps if you ask nicely they will tell you how you're supposed to do it. More interesting though is one of the discs is for Seiko in a Seiko package. So if Seiko sold replacement discs there would've been a way to change it and that would be in one of their manuals if we knew the part number and the watch it's supposed to go in.

Thanks, John,

So the back of the piezo must have a good physical contact with the watchcase?  No need for an airgap to permit vibration of the piezo diaphragm?

In my Timex watch, the caseback doesn't act as one of the electrodes, both electrodes are 2 independent springy electrodes.  I have bent them a little bit upwards, and the problem seems to be resolved.  Nevertheless, I would like to know the fitting procedure, in case I have further problems. Have already purchased 4 piezo elements from eBay.  What about shellac, epoxy, super glue?  With the first 2, I could incorporate an air gap, using super glue, not.

Never seen any mention of the voltage range acceptable in piezo elements.

Edited by boblalux
  • 5 years later...
KOwatch Watch Enthusiast

KOwatch

Posted
Posted

It looks like most of the peizo discs sold on ebay are mounted/glued on slightly larger copper discs (They look brass to me but ok). Some come with pre-soldered leads, one lead is connected to the peizo element, the other to the disc. In many watches, the ceramic disc is glued directly on the caseback which functions as one of the contacts.

I've got an older (70s/80s?) watch here with a cracked peizo that wants replacing. On closer inspection, there's a 20mm peizo element glued to a 27mm (stainless?) steel disc, where that larger disc serves as the second contact. This whole thing is glued into the caseback. I can chip away the ceramic element, I'm not sure if I'll be able to detach the larger disc, it's in there pretty good and there's no way to get it out really. Could try a soak to dissolve the glue with acetone maybe.

The elements are pretty thin, I'm hoping I've got room in the case to just glue another element over top.

IMG_0149s.JPG

 Share
Go to topic listing

  • Recently Browsing

    • No registered users viewing this page.

  • Topics

  • Posts

    • tonydagee
      Calendar work certina 25-651

      By tonydagee · Posted

      Hello all, just disassembling to service, but I can’t figure out the working of the calendar work…it’s not operational the jumper and spring are ok, but the operation of the driving wheel has me at a loss. I can’t see a cam to drive anything. Is something damaged or missing? Help please!
    • tIB
      Unusual Seiko dial damage

      By tIB · Posted

      Believe the relume (not a fan) was done a long time after the damage. 
    • Malocchio
      Unusual Seiko dial damage

      By Malocchio · Posted

      I can only think of some chemical reaction to reluming
    • nickelsilver
      A lathe with indexing that won't break the bank?

      By nickelsilver · Posted

      I have a little milling attachment for my WW lathe, but very rarely use it and not for wheel and pinion cutting. For that I use a small Sixis 101 milling machine. I normally do direct dividing, but sometimes have to do an odd count and use the universal index which also fits on the Sixis.   Back in the day when I didn't have a mill, I would cut gearing on my Schaublin 102. It has a universal dividing attachment which fits the back of the spindle. Both it and the one for the Sixis are 60:1 ratio, and with the set of 4  index plates I can do almost any division. When I've had to do a strange high count prime number, I print a disc with the needed division and just place the plunger on the dot. Any position error is reduced by a factor of 60 so still plenty accurate.   The machines are a mess in the pics as I'm in the process of making a batch of barrels for a wristwatch 🙃.   This is the Sixis. The head can also be placed vertically, as can the dividing spindle.   Dividing plates. The smaller ones fit another dividing spindle.   Universal divider for the Sixis. I put it together with parts from an odd Sixis spindle that takes w20 collets, like the Schaublin 102, and a dividing attachment from a Schaublin mill.     The dividing attachment for the 102. The gear fits in place of the handwheel at the back of the headstock.   And the little milling attachment for the WW lathe. I just set it on the slide rest to illustrate the size, you can see from the dust on it it really doesn't get used much. I think only when I change bearing in the head, to kiss the collet head seat (grinding wheel still in the milling attachment).
    • SidKop
      Opinions on Seiko's 4R and 6R movement quality from those more able to judge

      By SidKop · Posted

      I read a lot about the quality (or lack thereof) of Seiko's 4R, 6R, 8L  movements...or more specifically the lack of regulation from the factory. Especially when compared to similar priced manufactures using SW200's or ETA's. I thought I'd ask those more in the know, do the 4R's and 6R's deserve their bad reputation, is it fairly easy for someone with minimal skills (or better yet a trained watch mechanic) to dial in these movements to a more acceptable performance.    For background I spent more on a 1861 Speedy years ago, expecting that the advertised 0-15s/d  would probably perform more like 5-7s/d. In reality it's been closed to 2-4s/d. 
×
×
  • Create New...