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Old November 5th 15, 03:31 AM posted to rec.radio.amateur.antenna
Jeff Liebermann[_2_] Jeff Liebermann[_2_] is offline
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First recorded activity by RadioBanter: Jun 2007
Posts: 1,336
Default Solder Joints in Transmitting Loop Antennas

On Wed, 4 Nov 2015 21:24:55 -0500, rickman wrote:


I seem to recall some errors were reported, but I don't recall them
being of any consequence.


You haven't indicated if it's your model. I uploaded it to:
http://802.11junk.com/jeffl/antennas/magnetic-loop/Antenna_trans_LTspice/Antenna_trans_loop.asc
Is this the latest? This is what it produces:
Circuit: *
C:\blah-blah\jeffl\antennas\magnetic-loop\Antenna_trans_LTspice\Antenna_trans_loop.asc
Number of points per octave reduced from 3000000 to 19545.
Multiply defined .measure result: max
Each .measure statement needs a unique result name.
Date: Wed Nov 04 16:49:57 2015
Total elapsed time: 0.266 seconds.


Yes, I wrote the simulation with help from a variety of sources. The
above is not really an error. Just reduce the number of points used. I
don't recall how that is set, but much of it is parametrized.

I'm not sure what is up with the MAX error report. That sounds like a
problem with a line continuation.


That was the .ac directive. Too many points per octave.

Here's my tweaked version of the loop. No errors this time:
http://802.11junk.com/jeffl/antennas/magnetic-loop/Antenna_trans_LTspice/Rickman_60KHz_loop_02.asc
Screen grab of the output:
http://802.11junk.com/jeffl/antennas/magnetic-loop/Antenna_trans_LTspice/Rickman_60KHz_loop_02.jpg

What I done did:
1. Removed all the .MEAS stuff that was producing errors. Just put
the probe on the "output" line.
2. L1 and L2 were over coupled. I reduced the coupling from 1 to
0.02. I intentionally did NOT overlap the resonant peaks so the
tuning is slightly off. It's fairly close to critically coupled.
3. Adjusted C1 and C2 for 60 KHz tuning.
4. Change frequency axis (.ac) parameters.
5. I got lazy and didn't add the usual title block stuff.
6. There are no values for Rs which needs to be considered.

I hope this helps and I'm gone for dinner.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558