L & R Maxomatic Ultrasonic

[JerseyMo]

Has anyone here worked on an ultrasonic such as this one?  L&R Maxomatic..

I was told it will smoke when powered up. After opening it up I pulled the tube and right away I see it failed because the top cap fell off!

Also I noticed debris inside which of course is not a good sign either.  

So what to do?  I found a used tube for BIN at $20.00 and best guess is the machine is maybe worth $40.00 Is it something I should get into just for the fun of it?

Heck yeah, what is the worst I can be other than burning down the house

 

 

[oldhippy]

I've never ever seen one until now. How old is that thing?

[Tmuir]

As long as your competent with mains electricity wiring and your doing it just for yourself, go for it.

I don't know what the electrical laws are in the USA, but in Australia you would actually need a restricted electrical lenience to work on something like that.

A valve driven ultrasonic cleaner, that a first on me, I didn't even know they had been making them for that long.

[watchweasol]

Hi  Guys  I have an international ultrasonic valve driven  the machine works ok but the ultrasonic does not, Bought as a project several years ago still waiting to be done. I will post some pics sometime..  As JerseyMo's one is a single valve, get stuck in and have a go, It might make a big bang so power it up in the yard.

[dadistic]

Yikes!

"I was told it will smoke when powered up"

It sounds like someone has already let the Magic Smoke come out. You know, of course, that it won't work without it, and getting it back in is pretty tough :-)

[JerseyMo]

I was told the machine was made in 1975 but did not verify that.  No matter as I did go ahead and order a replacement tube. Someone else advised to replace any electrolytic caps. But, there are only two disk caps inside.  

I am assuming 'valve' is the same as 'tube'?

License?  Sure I got one of those!  

forgot to mention - you see the maker is located in Kearney NJ.  that is just a few miles from where I picked this machine up.

Edited February 21, 2020 by JerseyMo

[luiazazrambo]

If this is the same as yours ( nawcc ) the schematic might help you. If there is smoke there is a reason for that and you probably have to eliminate that otherwise you will end up replacing parts in an endless loop.

 

[JerseyMo]

20 hours ago, luiazazrambo said:

If this is the same as yours ( nawcc ) the schematic might help you. If there is smoke there is a reason for that and you probably have to eliminate that otherwise you will end up replacing parts in an endless loop.

 

Thanks, I came across that data sheet as well. The tube replacement will be as far as this repair attempt will go.  

[JerseyMo]

Ready for the next half century! and the first item cleaned was the knob of the on\off switch.

 

[dadistic]

That tube looks cool glowing away in there!

[watchweasol]

Hi   here are a few pics of my ultrasonic bought some years ago as aproject, got to get it done.

Its a british made National ultrasonic watch cleaner, It all works,motor,heater. The ultrasonic is dead and there is no life in the Valve(tube)  812A  Amplifier so the clean up begins an then I shall get a valve for it..

What was the one you got JerseyMo, was it the same an 812A,?...

[JerseyMo]

6 hours ago, watchweasol said:

Hi   here are a few pics of my ultrasonic bought some years ago as aproject, got to get it done.

Its a british made National ultrasonic watch cleaner, It all works,motor,heater. The ultrasonic is dead and there is no life in the Valve(tube)  812A  Amplifier so the clean up begins an then I shall get a valve for it..

What was the one you got JerseyMo, was it the same an 812A,?...

 

Yes, I found a 812A on ebay.

[watchweasol]

Hi   brilliant I found one, again on ebay so will invest the £20 odd pounds   China  seems no one else makes anything      Thanks       Cheers.

[watchweasol]

Hi JerseyMo     I dont know if you have the schematic for the L&R machine.  I found this whilst researching my national, Its not over good but better than nothing  if you are without.       Cheers 

[JerseyMo]

43 minutes ago, watchweasol said:

Hi JerseyMo     I dont know if you have the schematic for the L&R machine.  I found this whilst researching my national, Its not over good but better than nothing  if you are without.       Cheers 

Thanks,  the cleaner will be going back to work at my watchmakers shop. He had given it to me for an 'AS IS' sale on ebay. but of course I could not resist to take it apart and figure out why it was not working.  I should have told him it was just 'over wound'  and needed a servicing.   :)

[watchweasol]

Hi     I guess so.    I am a try and repair it man myself  Good job well done   , 

[Tmuir]

Nicely done.

Yes Valve and tube are the same thing, I still find it amazing that we can all be talking the same language and sometimes still not know what each other means. due to georgraphic variations of some words.

The one that creates the greatest confusion between Australia and the UK is the little rubber 'shoe' you put on your feet.

In the USA I think you call it a 'flip flop' in the NZ they are called Jandles (No idea why), in Australia we call them 'thongs' which I know in the UK and I think the USA is skimpy bathers which in AUstralia are called G-strings.

You can imagine the looks I got when I first went to the UK and told people that in the summer in Australia it was generally too hot to wear shoes and so I would usually just wear my 'thongs'

[JerseyMo]

according to Urban Dictionary

After a japanese swimming team came to NZ (many decades ago), one observer was so impressed with their style of footwear that he began making them himself - he came up with the word "Jandal" as an abbreviation of the term "Japanese Sandal"

 

 

 

[stonestonestone]

Mods forgive me for reviving this old thread, but I am trying to refurbish this exact machine and have no idea where a wire is supposed to connect to. Perhaps @JerseyMo knows? Thanks.

[AndyGSi]

Welcome to the forum.

Is the other end connected to the frame of the transformer?

[stonestonestone]

1 hour ago, AndyGSi said:

Welcome to the forum.

Is the other end connected to the frame of the transformer?

I believe so, yes.

[AndyGSi]

Then i expect it would be an earth to the case back.

[stonestonestone]

33 minutes ago, AndyGSi said:

Then i expect it would be an earth to the case back.

Thanks for the help. I don't see anywhere where it would connect to the case back, although I do see perhaps a spot on the oscillator/vibrator that based on the bend and length of the wire, I suspect it may go. The same connected wire goes up to one side of the body of the oscillator/vibrator, so perhaps this one is also supposed to be connected to it. Let me know what you think.

[AndyGSi]

Looks a good call to me, just the question is how was it bonded.

[stonestonestone]

On 4/4/2025 at 3:43 PM, AndyGSi said:

Looks a good call to me, just the question is how was it bonded.

Seems like it was just stuck into the epoxy. Would I be able to reattach it at another point on the body of the oscillator, or do you think that there is a specific terminal covered by that epoxy that I must connect it to.