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ENGLISH VICTOR · 13th Jan 2018, 1:19 pm

The LOPT shown is in fact a transformer made by Ferguson, They started to make sets for Marconiphone in the late 50s up to some time in the 60s.
I have repaired a few of those transformers quite successfully, the problem is that the start of the EHT winding is pulsed to the full potential of the line output valve anode, perhaps as high as 3.5KV.
Simply replace the inner insulated tube under the EHT winding, if you lose a layer of the start of the winding it will not matter. I can't remember but the core may need gappng with paper or mica to reduce core saturation. Just reassemble it the way it came apart The core material needs to be non absorbent and be highly insulating with low dielectric constant. I hope this helps and that the winding has not become carbonized at the edge.
Victor.

13th Jan 2018, 1:19 pm	#14
ENGLISH VICTOR Hexode Join Date: Feb 2008 Location: Sydney, Australia Posts: 356	Re: Dismantling LOPT's The LOPT shown is in fact a transformer made by Ferguson, They started to make sets for Marconiphone in the late 50s up to some time in the 60s. I have repaired a few of those transformers quite successfully, the problem is that the start of the EHT winding is pulsed to the full potential of the line output valve anode, perhaps as high as 3.5KV. Simply replace the inner insulated tube under the EHT winding, if you lose a layer of the start of the winding it will not matter. I can't remember but the core may need gappng with paper or mica to reduce core saturation. Just reassemble it the way it came apart The core material needs to be non absorbent and be highly insulating with low dielectric constant. I hope this helps and that the winding has not become carbonized at the edge. Victor.