NST Terry Filter Protection Circuit

KeeDx3, Sun Jul 30 2017, 07:15AM

What is the consensus on whether to buy or build a Terry Filter? I've already decided to use a protection circuit in my SGTC, but I just discovered that I can buy a prepackaged circuit from InformationUnlimited/Amazing1: http://www.amazing1.com/products/hv-suppression-circuit.html

I guess aside from taking some of the fun out of building a coil, are there any experiences with these? Are they as effective as a real Terry Filter?

For whatever reason, the link isn't working for me. But the product is called the SUP10, apparently good for 15kv @ 120ma
Re: NST Terry Filter Protection Circuit
hen918, Sun Jul 30 2017, 09:41AM

I've had some experience with amazing1's stuff, and it tends to do what it says it'll do, (it looks to me like a real Terry Filter) but for a high price!
For what you are getting, $200 seems a little steep.

The inductors can be wound with <$5 worth of parts, the MOVs and capacitors are also as cheap as chips. The resistors are $5 each. I cannot see how they can charge $200

I would make one myself.
Re: NST Terry Filter Protection Circuit
KeeDx3, Sun Jul 30 2017, 09:14PM

hen918 wrote ...

$200 seems a little steep.

The inductors can be wound with <$5 worth of parts, the MOVs and capacitors are also as cheap as chips. The resistors are $5 each.

I would make one myself.

And their unassembled kits are $120! I would think that the kit would be significantly cheaper, but nope. I like that it takes a lot of the guesswork out of things (I still have some confidence issues), but you're right that it's way overpriced, as are their 15/60 NST's.

Plus, I have seen some beautiful Terry Filters that really add to the aesthetic to the TC. Thanks for the feedback. I need to just put my fears behind me and build one.