Jump to content

Is this safe to use?


Recommended Posts

4 hours ago, gpraceman said:

I don't see any diodes.  I see one large resistor and a couple of selenium rectifiers.

A rectifier is a diode.

 

4 hours ago, gpraceman said:

A power LED would be nice, but that would take away from the original look.

I bought a pack of inline switches that have an LED indicator. That is the way to go.

https://www.amazon.com/mankk-Appliance-Control-Indicator-GW320-W/dp/B09B9MBXWP/ref=mp_s_a_1_5?crid=2PC4R7VJU9WHJ&keywords=ac+inline+switch&qid=1703330473&sprefix=ac+inline%2Caps%2C290&sr=8-5

Edited by LittleWatchShop
Link to comment
Share on other sites

5 hours ago, LittleWatchShop said:

A rectifier is a diode.

Ah.  From what I had been reading it does seem like those should be replaced.

The switch sticks in the down position, so that may also get replaced.  Seems just like a two position switch, so a momentary on SPST switch would do.  I see the capacitors rated up to 600V but not sure the voltage that the switch actually sees.

5 hours ago, LittleWatchShop said:

Great idea.  Having that, I could keep the demagnetizer plugged in but switched off.  The visual verification of it on or off, that the LED provides, is nice.

  • Like 1
Link to comment
Share on other sites

Once the various components are replaced, will it be more effective than a cheap modern demagnetiser?  If not why bother?  Genuine question's, I'm just interested.  I have two demagnetisers, one cheap Chinese one, works OK, one homemade, a central heating pump with the rotor removed, very powerful. 

  • Like 1
Link to comment
Share on other sites

3 minutes ago, RichardHarris123 said:

Once the various components are replaced, will it be more effective than a cheap modern demagnetiser?  If not why bother?  Genuine question's, I'm just interested.  I have two demagnetisers, one cheap Chinese one, works OK, one homemade, a central heating pump with the rotor removed, very powerful. 

The cost of a new instant demagnetizer is rather expensive.  An Elma unit from Cousins is £207.95.  Even with replacing components on the vintage unit, it should be significantly less cost.  Not sure on the cost of components yet (which should not be a lot), but I only paid $50 for the unit.

  • Like 1
Link to comment
Share on other sites

2 hours ago, RichardHarris123 said:

Once the various components are replaced, will it be more effective than a cheap modern demagnetiser?  If not why bother?  Genuine question's, I'm just interested.  I have two demagnetisers, one cheap Chinese one, works OK, one homemade, a central heating pump with the rotor removed, very powerful. 

Cheap, to rebuild. Far better than the cheap units IMHO.

The big cap is $10. All of the other components total less than $5

  • Like 1
Link to comment
Share on other sites

I found an Elimag schematic that is pretty close to what I see with this L&R unit.  I made some alterations to it reflect what I see with the L&R.  With the L&R there is an extra capacitor, the 0.05 uF capacitor (the one in my photos that is not all waxy/oily).  Not sure what the purpose of that one is.  There is no 220 Ohm resistor or a resistor for the light.  Though maybe the light has some internal resistor.

It looks like I made a mistake on the switch.  It is a SPDT.

L&R schematic.png

ellimag schematic.png

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.



  • Recently Browsing

    • No registered users viewing this page.
  • Topics

  • Posts

    • I've also heard it called the "top side" and the dial side the "bottom side", which should make any non-repairer very confused. There are many examples and sometimes it comes down to personal preference. Personally, I like to say "dial train" whereas most other people would use the term "motion works".
    • Is magnetism such a major problem that we (as home hobbyists) need to spend $$$ on a fancy demagnetiser? I use one of the cheap blue Chinese demagnetisers (£10 from ebay). It works, and has never failed to demagnetise a movement, or my screwdrivers. Magnetometer - who needs one?  Take a very small screw. If it sticks to the clean part, it is magnetised 🤣
    • My overall preference is to use traditional names and terms, that became my habit when i was taught joinery by old boy chippies 2 generations older than me , that had their time in the 40's. But what i often do is adjust the names and terms i use according to who I'm talking with. Sometimes i will say trainside and occasionally watchmaker's side. I try to find a balance between accommodating other folk ( there's no point speaking a foreign language to someone who doesn't understand it ) and using a name that appears to me to be more relevant as to its use or description. But using the name lever can be quite confusing,  some watches might have parts that are also levers, release levers, which in effect is what the pallet fork is, an escapement release lever. 
    • Then put the case number in here https://www.cousinsuk.com/category/filter/search-seiko-case-parts and it should give you the crown 
    • I come across to replace the crystal of a 7734 chronograph.  What make it special there a printed chapter ring  which fits inside the recess of crystal before inserting into the case. I am thinking of a high dome crystal such as Sternkreuz ATCH, fitting diameter OD332/ID320.  For this purpose, tension ring will be removed and fit in the chapter ring.  I understand the crystal size may not perfectly fit these two dimension.  Should aim to find the right ID, then OD can be grinded to reduce without much difficulty.  To find the right crystal, the easiest way is to get know of the OD/ID relationship of Sternkreuz ATCH/ATCG (otherwise the OD of the crystal and tension ring).  I hope you are able to help to minimize the trial and errors.
×
×
  • Create New...