[GreenKeys] 88 mh toroids,

[Rokumon Cat]

Hi Frank,
 
The 88mH torroids were what were called "loading coils". They were installed every (I think) six thousand feet on twisted pair cabling, and three  thousand feet from the telephone CO. Their purpose was to neutralize the capacitance of the twisted pair wire, the effect being that the volume of the audio on the loop was maintained. Without the coils, the volume would quickly diminish, and static/solar/lightning noise would soon drown out the speech volume. 
 
All the coils that I have seen are not bifilar wound, but I am not saying that they did no exist. They also have many uses other than telephony, including being used in RTTY filter construction. I have plenty so I will let others have them.
 
As far as shellac is concerned, I have never liked a shellac finish. It always seems to get sticky. Much prefer a nitrocellulose lacqure finish. Easier to fix if it gets scratched, but with the current state of affairs of the eco-nazis running everything, it is next to impossible to find any more except in luthier supply shops where it is waaaaaaaay too expensive.
 
Joe 

--- On Fri, 6/17/11, kf9nz at juno.com <kf9nz at juno.com> wrote:


From: kf9nz at juno.com <kf9nz at juno.com>
Subject: [GreenKeys] 88 mh toroids
To: greenkeys at mailman.qth.net
Date: Friday, June 17, 2011, 6:13 AM


        One of my sons-in-law is a cable splicer for AT&T.  Some time
back he gave me a huge plastic closure full of loading coils.  I have
only partly tried to get the thing open, and it looks like a lot of work
to recover the toroids. They are potted.   I have been putting off that
project for over a year now.   Anyhow, we stopped by his house to see the
grandkids a few days ago, and he handed me a small cardboard box.  In it
were eight brand new 88 mh toroids.  Two are mine, but anyone wanting one
or two, it's first-e-mail-first-shipped until 6 are gone.
        Anybody want to explain what these are for to those who don't
know about shellac either?
Frank
____________________________________________________________
57 Year Old Mom Looks 27!
Mom Reveals $5 Wrinkle Trick That Has Angered Doctors!
http://thirdpartyoffers.juno.com/TGL3141/4dfb530cd46525d643fst01vuc
______________________________________________________________
GreenKeys mailing list
Home: http://mailman.qth.net/mailman/listinfo/greenkeys
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:GreenKeys at mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html