[Prev][Next][Index][Thread]

TT-42 update



Hello coilers,

I finally got the TT-42 coil running with it's new base, so it's now a
portable TC.  The bottom of the base is a piece of plywood about 
15" by 14".  Three wooden legs from old style TV's hold a "wye"
shaped piece of wood above them, and the flat primary is mounted
2.5" over that.  The new small rotary, the unpotted 12/30 NST, and
the Maxwell 0.0147uF cap is mount on the plywood.  The coil
definitely has a unique look to it.  The entire TC is 39" tall from the
base to the top of the top toroid.  I'm using a 1.5" x 6" spun aluminum
toroid with a 4" by 13" spun aluminum toroid above it.

I've posted new photos showing the TC with the new base at my
website. 

   http://members.aol-dot-com/FutureT/TT-42index.html

The secondary has a wooden post at the bottom, with a brass
screw at the bottom of the post.  There is a wooden socket mounted
to the "wye", and there is a brass flat head screw at the bottom of the
socket, so when the secondary post is dropped into the socket, the
brass screws make contact.  This way, the secondary does not need
any kinds of bolts, etc to make the electrical ground connection.  
This makes it convenient for fast setup in the portable realm.  

I built a small simple safety gap to ground out any strikes that might
loop down and hit the primary.   The NST doesn't have any other 
protection.  There is no PFC.  I just used wire nuts to connect the
power cord to the NST primary.  I still have to improve the method of
tapping the primary, to give me more tune points.  I think the tuning
is off slightly because my sparks are only about 38" instead of 42"
max.  I was getting 42" before when tapped at 15 turns, but now that
I'm tapped at 14 1/2 turns, I'm getting just the 38" sparks.

Cheers,
John Freau