in that case - be sure that either screw is electrically isolated on one ( even better - both ) ends ..... or that your screen-bell is electrically isolated from bottom of case , so you are not having shorting turn through donut itself
wire in windings is also isolated from core , electrically ..... but not magnetically
wire in windings is also isolated from core , electrically ..... but not magnetically
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I'd wait to say that till I was absolutely positive what it means in Serbian.
(Eek me, Z)
A piece of pipe can be bought by the cm/inch.
The lid can be made with a generic electric drill, a metal file, and patience.
Leaves the acetylene & oxygen bottles, and a lighter.
Toroid shield
Another option, to preserve the clean looks of the shield. Use a good silicone to bond the shield over/around the transformer. Silver solder a piece of wire or braid to the bottom edge of the shield, and run it to a good chassis ground (or just let the shield "float", ungrounded, if hum is not a problem). Result is a grounded shield, with no bolts/nuts showing in the top, and with no dreaded "magnetic loop" around the toroid core. Voila.
(Now, back to the "photos" in this Pass amp photo thread!.....
)
Hmm... I didn't know that there still are possibilities for the electrical loop when trafo center is "metal free", but now that you say it makes sense with the magnetism and all. Well I have to make myself a nylon bolt then.
Another option, to preserve the clean looks of the shield. Use a good silicone to bond the shield over/around the transformer. Silver solder a piece of wire or braid to the bottom edge of the shield, and run it to a good chassis ground (or just let the shield "float", ungrounded, if hum is not a problem). Result is a grounded shield, with no bolts/nuts showing in the top, and with no dreaded "magnetic loop" around the toroid core. Voila.
(Now, back to the "photos" in this Pass amp photo thread!.....
)The transformer that I bought is designed for audio applications and have a minimal magnetic leakage so the cover is probably not necessary. I made it because the inside of the amp will be more "clean" looking in my opinion. If it also shields the trafo a little I consider that a bonus.
I'm with you 100%. It does look great and worth the effort on that basis alone. I was just curious because it looks tough to have so many diverse elements in a case without interference. I wondered if some level of scrutiny for their physical arrangement wasn't worthwhile. Then... I was thinking way back to my EE transmission line lab and our measured results for line-of-sight, ungrounded shields were not very good. Someone here may have some real emag experience to refute my observation but maybe an insulated cover would be mainly cosmetic? but hey, from a guy that buys chrome valve covers... i still like it
