Re: Both Terry filter and RFI filter?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Dr. Resonance" <resonance-at-jvlnet-dot-com> 



Yes, use a RF line filter.  Also, use an RF "hash" filter in series with
each line.  This is 80 turns of # 12 AWG wrapped around a 2 inch ID PVC
tube.  Tube is filled with 1/4 inch dia. steel/iron rods --- epoxy or
silicone in place.  Corcom filter plus this hash filter will keep everything
out of the AC line.

You can buy surplus Corcoms from C&H Sales, Pasadena, CA or Fair Radio
Sales, Lima, OH, at around $10 each.

Dr. Resonance

Resonance Research Corporation
E11870 Shadylane Rd.
Baraboo   WI   53913
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Wednesday, May 05, 2004 11:19 PM
Subject: Both Terry filter and RFI filter?


 > Original poster: pepperman-at-softhome-dot-net
 >
 > When using a Terry filter to protect my transformers, do I also need
 > a separate RFI filter to keep the interference out of the mains?  If
 > so, what frequency response is acceptable?  I recently looked at
 > some commercially available filters and found out that most of the
 > units they sold only went down to 150 kHz, although a couple of
 > the more expensive ones went all the way down to 10 kHz.
 >
 > In case it matters, I was looking at filters made by Corcom (which
 > was recently bought by Tyco), specifically the B series 20-amp
 > model (cheapest series); the series that filters all the way down to
 > 10 kHz is the T series, but it costs quite a bit more (~$88 vs. ~$23).
 >
 > I'm building a largish coil (still undecided on some of the specs, but
 > it'll be an 8"-12" coil, hopefully around 1.5 kVA), so the resonance
 > frequency might be below the ratings of the RFI filters, but I'm not
 > sure if that matters or not.  Where does most of the RFI noise that
 > we're trying to filter out come from, anyway, and in what frequency
 > range?
 >
 > So, do I need a separate RFI filter, and if so, will bottom of the line
 > model work fine, or would it not do much for keeping noise out of
 > the mains?
 >
 > Michael Johnson
 >
 >
 >