On the bench today… Ultrasonic cleaner repair.

So, the cheap ultrasonic cleaner wasn’t great from the start, it would take about five minutes to start up and when it did it was like a mouse fart. It worked for a while and was useful in it’s own way.

In the mean time I bought a larger capacity one and took this home for small jobs.

So now comes the time i need it to clean up some parts and it fails completely. Poop.

After taking it apart, it seems they are quite well made for the money, everything is shielded in the right places and ground points are well attached etc.

The ultrasonic transducer was toast, probably not that great from the start, but there you go. Also the resistors between the Base and Collector of the driver transistors were charcoal.

Which left me in a bit of a dilemma. What were the values? There was nothing on the internet and the company hadn’t lasted long enough to complain, let alone get any information from.

Then a thought popped into my head, I wonder if the other ultrasonic cleaner had a similar drive board in it. A week goes by and a trip to workshop one was overdue. To my relief, the other ultrasonic cleaner had the same board, and being a much later version had some modified and upgraded parts too.

The original resistors measured around the 30k mark, but looked like they started life in the 10k – 11k range as there was still one undamaged band left on one of them. The new beefier resistors were now 47k (five band jobbies, so yellow, violet, black, red, brown) (470×100 Ω ± 1%).

Anyway, checked everything else was ok, which it was, fitted some new resistors, and ordered a new transducer. The ones fitted in this range are 40khz @ 60watts. Just for reference.

So that’s how far I have gotten with this so far. I will have to wait for the new transducer to turn up and see how things go. Watch this space…

Roberts Radio button chromes…

..or moreover, the lack of therein. Roberts radio’s seem to have particular propensity to losing these things at an alarming pace. And I have a significant amount of radios that require them. So I decided to make some…

I had to make former to place them on to finish off the surface on the top, but I think they finished up looking rather nice.

Finally…

Ok, so not so long ago, there was a breach of security, a virus was uploaded to the server, and I lost the whole website. A bit of a day wrecker. Anyway, never mind, I’ll go get the backup drive, nope, that had died too.

So, up until now all of the posts were lost, that was, until now. I bought a box full of bits and bobs, and in with it all was a hard drive of the same model of my dead one.

A few chip swops later and I have a mostly working backup drive. It has massive corruption, (probably due to the original failure) but I have been successful in reconstructing lots of the lost entries from the past. So, from time to time more and more older posts will appear here when I have reconstructed them. Yay.

On the bench today is… A Longines Quartz watch.

Just another quick post today, a strip, clean (in the cleaning machine), rebuild and re-oil of this Longines Swiss quartz watch with an old ETA movement, plus a new battery and then a timing setup.

Above – before the calibration. One second fast a day.

Above – after the calibration. Spot on.

On the bench today is… A Black 746 Telephone.

There’s been quite a demand for black telephones of late. I’m not sure quite why, but I’ve got to go with the flow and repair and polish up some more.

Above – The usual condition they turn up in. After a full clean, polish and replacement of the broken parts, such as leads, dial mechanism parts, and then fitting a concussion diode and a REN dropper resistor, all is well again.

Above – Final touches like fitting a newer type microphone for better speech and a centre number card finish off the refurbishment.

We have lots of lovely telephones in stock, including trimphones and novelty telephones, so just give us a call, to see if we have what you need.

On the bench today is… A Geneva Swiss quartz watch

Just a quick post today, a basic strip, clean in the cleaning machine, rebuild and re-oil of this Geneva Swiss quartz watch, plus a new battery and then a timing setup.

Above – before the calibration. Nearly two seconds fast a day.

Above – after the calibration. Lovely, can’t get better than that.

On the bench today… Old Rolex Oyster

This one came in for a half service and a clean up.

Sadly my camera decided to lose all of the pictures of the strip down, clean and rebuild. Which is a shame.

This watch is quite badly worn, as it had not been serviced in the thirty years since it’s purchase, so even after everything, it still only runs unevenly, which is a shame, but when I say unevenly, I’m talking about a fraction on a second every minute, as you can see from the timegrapher above. Overall, the gain or loss is zero seconds a day, which was all the customer wanted anyway.

Yes, the beat error is out, I can see that. 🙂 However the Rolex tool to adjust that out, is ridiculously expensive and the customer wanted it done for next to nothing.

I’m Back!

Hello again, and welcome back to the website.

Due to unforeseen circumstances, the website got infected, and all things went a bit pear shaped.

So obviously, more content will be popped up here when it can be, in the meantime, Visit the little shop at-

27 New Street on the Barbican in Plymouth,

or you can get hold of me by e-mailing the web address.