Mercury Arc Rectifier

[bobhowe]

Did anyone see todays antique roadshow on BBC1 ? there was a mercury arc rectifier on one of the antique shops in Melrose no one bought it what a shame

[Dave Moll]

Do you mean the Antiques Roadtrip? The Antiques Roadshow is the one where people bring their possessions simply for a valuation - with no buying or selling.

[Ed_Dinning]

Hi Bob, I missed the MAR, but the shop at Old Craighall (?) near Dunbar seemed to have a range of interesting items.,


Ed

[bobhowe]

Hi David my mistake it was the Antiques Roadtrip hi Ed it was only on screen of a matter of seconds as James Braxton walked past it would like to have one but i think her indoors would draw the line

[cathy_vintage]

Ash here ... In the early 90's I went to the Royal Opera House, Covent Garden to look at the feasibility of automating some of the scenery drops. We never took on the job but we got a fascinating tour of the place. The stage was rotated I think by an ex-U boat DC motor (well that's what their technical guy told me it was). He showed us the rectifier room, which had massive mercury arc rectifiers and they were still in use. In there it was like a replica of igors den from the horror movies.

The rectifier used is shown here in the attached pic.

[Nymrod121]

"Stage call for Mr Lucien Nunes ... you're up - !"

[Dave Moll]

Originally Posted by Ed_Dinning

Hi Bob, I missed the MAR, but the shop at Old Craighall (?) near Dunbar seemed to have a range of interesting items.

I found it rather frustrating in the shop with the big coils and other interesting-looking items - as one got the briefest of glimpses as the camera panned past. Maybe I'll have to take a look on iPlayer where I can pause the picture for a longer look - and check out the MAR, as I too missed it.

[raditechman]

Cathy Vintage:
The Merury arc rectifiers which were at the Royal opera House, Convent Garden are now on display (and working) at the Kempton Steam Museum.
http://www.kemptonsteam.org/history/arc-rectifiers/

John

[cathy_vintage]

Ash here .. Thanks for that link John, So it was correct about the U -boat motor! It's weird because prior to that it was powered I believe by 750 PSI water hydraulics pressure from London Bridge & I work 3 days now for a company called 'The Water Hydraulics Company. Those mercury arc rectifiers arcing and glowing at the Royal Opera House certainly were an eerie sight.

[Radio Wrangler]

I remember reading about, I think it was called the London Hydraulic Power company who had steam powered pumping stations providing high pressure water to customers. The bascules at tower bridge used it and the revolving stage at the palladium. The attraction for theatres was said to be its silence.

David

[dseymo1]

Yes, Some of London Underground's lifts were powered by London Hydraulics. Their disused ducts were, I believe, taken over by Mercury Telecom, allowing them to lay their cables with minimal disruption.

[greg_simons]

My first boss way back in the early seventies had been a cinema projectionist during the golden days of the thirties, he turned up unexpectedly one evening and took me to see the equipment at a cinema he worked at, it still had the original cabinets with huge mercury vapour rectifiers supplying the huge projectors and the huge fader pots for the house lighting, I think the place was in the process of being dismantled but he wanted me to see it as it was because it was something I would never see again.

[Radio Wrangler]

Old Craighall is a tiny village and a very large roundabout on the A720/A1 Edinburgh bypass (at the top of the A68) It is on the way to Dunbar, but is pretty much a shop-free zone. I'm not aware of anything interesting there.

Melrose? Mercury arc rectifier in a shop? Lucien must be on the road North! I'm currently beside the A68 just South of Jedburgh so he might be coming past any time.

David

are now on display (and working) at the Kempton Steam Museum.

Which is open next weekend (24th, 25th) in steam, I went there years ago, it was fantastic. I am going again on the Sunday as there is a classic bike/car show too. Take one of the no extra cost guided tours. Only £7 entry.

[M0FYA Andy]

Google found the antiques shop straight away - https://www.earlytech.com/earlytech/

Andy

[kalee20]

Originally Posted by Radio Wrangler

I remember reading about, I think it was called the London Hydraulic Power company who had steam powered pumping stations providing high pressure water to customers. The bascules at tower bridge used it and the revolving stage at the palladium. The attraction for theatres was said to be its silence.

Yes, LHP pressurised water was used by many passenger lifts, curtains at the Odeon, Marble Arch. But not the Tower Bridge bascules - these used local steam engines to generate locally pressurised water to operate the bascules. (Now, they use electric motors to pump oil to operate the bascules, which strictly isn't proper hydraulics of course!)

I've never been lucky enough to have uses a MAR - I have seen them removed from service and that's the nearest I've got! I've worked with a Westinghouse rectifier set from 1936 for carbon arc lamps, and by Sod's law it had to use fan-cooled copper oxide rectifiers...

[Radio Wrangler]

There used to be a MAR demo in the science museum which I saw in about 1964. I then understood the blue glow from the sandstone building that powered the trolley busses to our village.

David

[peter_scott]

Now there's an interesting coincidence!

Michael Bennett-Levy lived (or possibly still lives in) Monkton House, Old Craighall before he sold off his collection and moved to France for reasons of ill health.

Perhaps Bonhams didn't sell all of his collection and he has returned to Scotland.

Peter

http://www.scotsman.com/lifestyle/40...ance-1-1206513

http://www.bonhams.com/auctions/17616/

[raditechman]

Apart from seeing the ones at the Kempton Steam museum I have worked in a job with mercury arc rectifiers in use.
For a few years from 1961 I was showing films at the Odeon Cinema, Richmond. We had 4 mercury arc rectifiers. 2 supplied the power for the 2 carbon arc lamps on the projectors. A spare "stand by" and another under the stage to power the lift for the organ console.
The projector rectifiers had their own room!.

John

[Ed_Dinning]

Hi Gents, I was lucky enough to get to play with them as part or the labs on my degree course in the 60's.
The Melbourne museum is trying to get a demo going in one of their galleries.

Ed