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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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Old 12th May 2019, 3:04 pm   #1
Steve G4WCS
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Default Valve identification please

Going through some valves and found this.
Box says PEN A4 but it doesnt look like one.
Only marking is a V on the base.

It appears to be new.
Any ideas
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Old 12th May 2019, 7:24 pm   #2
Megatron
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Default Re: Valve identification please

i will put forward the suggestion

an Marconi Osram MKT4/7.
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Old 12th May 2019, 11:41 pm   #3
Alf
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Default Re: Valve identification please

I'd agree MKT4/7
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Old 13th May 2019, 9:11 am   #4
Steve G4WCS
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Default Re: Valve identification please

superb, thanks guys !
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Old 13th May 2019, 1:46 pm   #5
Mr Moose
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Default Re: Valve identification please

Hello,
It could be a MKT4 but this is a low slope 1amp heater valve and not equivalent to the PENA4. The equivalent to the PEN4A is the high slope 2amp heater N41 https://www.radiomuseum.org/tubes/tube_n41.html
(There is also the N30 with a 13volt heater)
Yours, Richard
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Old 15th May 2019, 12:12 pm   #6
snowman_al
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Default Re: Valve identification please

MKT.4/7 it is. Box is wrong...
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