Thread: Eric Dollard
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Old 08-15-2013, 10:26 AM
David G Dawson David G Dawson is offline
Senior Member
Join Date: Mar 2008
Posts: 421
Crystal Set Initiative

Thankyou for your interest.
Picture is one I sent to Eric of Coils #1 (Accidental and having same length as secondary), #2 (Erics) & #3 (11 awg test) and Coil # 4 of the 20 awg is similar to # 1 in appearance and having the same Inductance.
AM Station Frequency = 1557 Khz.
Diameter of primary and secondary is 488 mm (19.2").
Extra Coil is 195.2 mm (7.68") and having 50 turns but made a few extra for tapping purposes but find a reduced number of windings was better like 48 turns.

Length was calculated that the 50th turn equalled diameter or close to it, i.e., 'square' except for the 11 awg which is slightly longer.
The picture has the coils connected to a 30 meter aerial strung into the bushes and I was testing each for AM reception and using the two 1N34 diodes on the pick-up head as the receiver for comparison.
No matter what I did, Erics was always the way poorest performer in both this test and test on the working TMT - way too many turns and wire too small, destruction by L & C.
Test here was by contact to detect an AM EM signal and not through the air as at the actual Extra Coil at the TMT.

Made up a circular 600 x 900 mm aluminium sheet tank today to completely surround the Extra coil and didn't matter whether it was connected metal to metal or insulated, the reception was improved from the air receiver some 15" away.
My hand in close proximity to the tank managed to amplify the signal slightly where normally it would do the opposite.
I had a notion that I would be able to light a small Led between the two ends of the aluminium but was not the case.
This test kind of proves the signal is other than Hertzian as the aluminium is shielding the receive head.

The test of the Extra coil inside the secondary was a failure due to I believe, the spiralling motion of the LMD signal away from the primary/secondary coils at the top side but the Extra is radiating out in all directions.


Last edited by David G Dawson; 08-16-2013 at 12:43 AM. Reason: Picture Size
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