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Components and Circuits For discussions about component types, alternatives and availability, circuit configurations and modifications etc. Discussions here should be of a general nature and not about specific sets. |
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5th Nov 2014, 5:32 pm | #1 |
Dekatron
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 14,010
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"ADZAM" valves?
I need - or at least I think I do - a replacement UCH42 frequency-changer for my rather-well-used Eddystone 840A restoration. The one fitted [Mullard branded, I reckon it's the original] seems to have insufficient 'oomph' in the triode oscillator-stage to function reliably as an oscillator on the highest-frequency band.
Langrex seem to have UCH42 valves for £6 - but they're branded "ADZAM". Is this a genuine worth-buying brand? OK, I know it's MAZDA spelled backwards - but http://www.r-type.org/exhib/aas0041.htm implies it was a RCA brand? If so it inspires confidence. http://www.radiomuseum.org/dsp_herst...ompany_id=6922 sort-of suggests they were involved with Phillips too. I'm thinking "It's only £6 so what's to lose?" but am I buying a pup? |
5th Nov 2014, 6:10 pm | #2 |
Dekatron
Join Date: Nov 2003
Location: Heckmondwike, West Yorkshire, UK.
Posts: 9,643
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Re: "ADZAM" valves?
Could be Mullard:http://www.tubemongerlib.com/gallery...itain.jpg.html
I suspect that they're a French rebrander |
5th Nov 2014, 6:11 pm | #3 |
Dekatron
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 14,010
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Re: "ADZAM" valves?
I'm hoping you're right!
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6th Nov 2014, 3:16 am | #4 |
Dekatron
Join Date: Dec 2007
Location: Haarlem, Netherlands
Posts: 4,203
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Re: "ADZAM" valves?
Adzam was indeed a Philips owned brand. You can always recognise a Philips valve by looking for two lines of 3 or 4 characters near or on the base. Those encode both the valve type and revision as well as the factory (Mullard, amongst many other Philips owned or associated factories) and the year and month of manufacture.
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6th Nov 2014, 12:30 pm | #5 |
Hexode
Join Date: Apr 2008
Location: Ramsgate, Kent, UK.
Posts: 252
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Re: "ADZAM" valves?
A little history...
Contrary to a lot of popular belief on the web, ADZAM valves are not export branded MAZDA (UK) parts or rebrands. ADZAM valves were produced by the Belgian company M.B.L.E. (Manufacture Belge de Lamps Electriques) which started life in 1911 by making filament bulbs under the name MAZDA. In 1924 they turned to the production of valves from their factory in Brussels under the brand name of ADZAM because of legal reasons - it was likely that MAZDA was already registered as a brand by BTH at the time. MBLE was absorbed into the Philips empire in 1957 and were given the ‘factory code’ L as seen on their products. As with all Philips group-produced valves, the branding on the envelope was no indication of the manufaturer, for instance an ADZAM branded part could be made in Blackburn, Heerlen, Chartres, Hamburg… |