Thread: Unknown valves
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Old 9th Aug 2019, 6:33 pm   #4
Marconi_MPT4
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Join Date: Mar 2011
Location: Dorset, UK.
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Default Re: Unknown valves

Hi,

Centre spigot size might suggest Mazda octal, and if so with pin 7 missing these could be SP41/61. Height is similar.

Large one to the left in the first picture reminds me of Marconi/Osram KTW61 or KTW63

Cheers
Rich
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