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Old 1st Sep 2019, 8:14 am   #13
stitch1
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Join Date: Jan 2008
Location: Durham, County Durham, UK.
Posts: 592
Default Re: Grey insulating cardboard

Quote:
Originally Posted by Terry_VK5TM View Post
Yes, "Elephantide"

The use of ordinary cardboard is fraught with danger.

In damp/humid climes, it can absorb moisture and not only become conductive but it also promotes corrosion when in contact with metallic surfaces.

If you really, absolutely, must use cardboard, soak it in varnish or shellac and let it dry thoroughly before use.
Elephantide or Presspahn is still available. I restored a VHF81 and the service sheet said ‘slide the Presspahn heat deflector out’ but it was missing, I was pleasantly surprised to find they were still going and I ordered direct from them.

https://secure.presspahn.com/Cart/in...2g8li0aihgugg0

John
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