Hugz wrote:I'm sure Peter you are going to need a lot of JM Villiers coils to perfect your renewed vocation!
This is becoming interesting. Could very well be I will revise my original " no rewind service" but time will tell..........would hate to wreck somebody else's coil in perfecting this. Watch this space Hugo, but bear in mind the shipping costs!"
Need to get 100% guaranteed perfect info on every wrinkle on how these were made before going further, and I'm in no hurry. As Allan quite rightly observed there is nothing that can't be remade if you are prepared to put enough time and effort in to it. Keep in mind here that somebody was winding a specialist EHT transformer using 1930 - 40's technology that became, leaving aside the basic physics, everyday bread & butter routine by the time that mass produced TV line output transformers came on the scene in the 60's and 70's.
I only posted a couple of the tens of pics and measurements I took this afternoon on this post mortem; this was the simplified explanation to answer the question on the shorted turns proposition. (boredom and anorak postings would have become unbearable if a full account had occurred
)
The unresolved question will be whether we are attempting to "undetectably restore/repair" or make a form, fit and function replacement. This will determine the rebuild processes that we WILL develop here for use on this forum. I don't accept that a rewind can't be done if a suitable process is developed with the kitchen table in mind.
For example this coil achieves a layer thickness of about 14 thou with old tech cloth insulation.... this could be much thinner using contemporary (eg mylar) based insulation. However this would result in a much thinner overall winding diameter and increase the gap between finished coil and the casing making the current outer, very elegant, connection using capillary action impossible without some sort of compensating frig..... But it can be done!
Lots of swings and roundabouts ........... ( Florence had patience , Zebedee just lucked/ crashed out ..............)
Peter
ps My coil went open circuit two layers in, just after the 3.75 inch long strain relief section. No chance of repair without stripping it.......
pps The pic of the Proj Manager desoldering the coil lead in the last post was pretty much gratuitous; only included to show her liking for latex (gloves)........
