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Old 08-30-2013, 12:04 PM
Sebacid Sebacid is offline
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Join Date: Jul 2012
Posts: 18
Originally Posted by dR-Green View Post
Hi Sebastian. Yes PVC tubing will be better than wood. Also ideally you should design the coil for a specific frequency/radio station, 1000 kc is a general example. When tuned to different frequencies the magnification factor will alter, the goal is to have highest magnification factor at the intended frequency so different tuning will work against this. Although you will need to experiment to find the highest magnification factor with a given design anyway.

For the overground wave reception you should use a normal crystal radio or a normal radio receiver. You need to receive the signal as normal and then measure the difference.
Hi Dr. Green,

Thank you for your insight, I will have to do some searching on a AM radio station near me (Finland). The problem here is that almost all of the broadcasting stations have ceased using the AM frequencys. I think the nearest one is in Holland?! Not sure on this, must check.

In the calculations for the extra coil, I get a totally different total lenght of coil if I use the formulae by Eric to calculate it?

Tesla's Colorado extra coil had the same amount of wire as the secondary (800m). Should I go with this or trust the formulae?

Thanks again,


Post edit:

Found a radio station from Sweden, Stockholm radio that broadcasts at 1710Khz AM frequency. I think it is still operational, so I will try working with this frequency. The last AM radiostation in Finland ceased to operate in 2007. Any other known operational frequencys are welcome!
Time to do the calculations again!

Last edited by Sebacid; 08-30-2013 at 12:55 PM. Reason: Adding information
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