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Old 04-21-2012, 01:48 AM
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jake jake is offline
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Join Date: Nov 2007
Posts: 169
Originally Posted by xee2 View Post
Congratulations. Thanks for the report and photo. Is your only antenna the short wire on top of the primary coil (or are you connecting to an external antenna wire in addition to the fireplace ground)? Please post a link to the page where you got the EPD info.

First four equations are the most important as far as I can tell. (wire length, turn length, coil diameter, coil hight) Primary width is 18% of coil diameter but I cant find the post. It's somewhere on the "Peter what happened to Eric" thread, search the T-Rex posts. If you can figure out how to incorporate the other items into your build without loosing the first 4 the the better according to EPD. Not having the correct size tube, I used 14 gauge as recommended by Eric. Coax is also recommended by Eric but I felt this was a compromise to another extream, so I went with the 14 gauge solid.

There are a few excell calculators on the yahoo group. I wrote the TRTcalc3.xls. These will do the math for you. If you are not a member PM me and I will send it to you. We cant post excel files here. Now that I think about it I should update that spreadsheet again.

As you know from you exciter experience there are variables in designing a coil. This way, adds a few more variables in the mix. This coil is based on a few ideas EPD described in his writings and old school HAM techniques, brought back to life by EPD. Spaced windings, active copper volume match
and Erics formule were a few of my considerations.

The extra coil is still a bit of a mystery. I am not using one. I made one but I have not figured out what it is supposed to do, and how it does it. Erics dimensions were tenetive(as he described) at best and not all the equations make sense to me at least. I am almost ready to revisit that.

ALSO I got an LED AV plug to glow just as well as the FWBR. One wire to the top of the secondary and another lead off the negative of the LED laying on the tile.

The fireplace is metal and sticks out of the roof so its like an antenna. but its grounded so I dont know what to call it.

OK fireplace not needed!!!

I connected to the mains ground and adjusted the CAN, now the LED is on, bottom of the secondary is mains ground and soda can antenna.
Attached Images
File Type: bmp trtschem1.bmp (278.0 KB, 30 views)

Last edited by jake; 04-21-2012 at 03:50 AM. Reason: 2 banana
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