Re: Information Unlimited BTC30 coil

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx>

There are probably a lot of things you could do to upgrade the BTC30.

1. High Voltage Supply: I believe the BTC30 is a 20mA output. 
Consider replacing to a 30mA or even 60mA.
2. Spark Gap: If the spark gap is a simple 2 electrode fixed gap 
without air cooling, add the air cooling. This will aid the coils 
ability to run longer. You may even consider building a multi-segment 
gap which aids cooling. Again, due to the small high voltage supply, 
the new gap should go along with a higher current transformer.
3. The primary is likely fine the way it is. It's specifically 
designed for the tank cap size. Should you go to a larger supply, the 
cap could be resized also (and resized to maintain the same primary).

Although those are some ideas, a better idea is to design your own 
coil from scratch with the goal to have the new coil throw 3 times 
the sparklength than the BTC30 is capable of out of the box.

Take care,
Bart

Tesla list wrote:

> We are building the BTC30 coil during physics class at school.  I 
> was wondering if there was any way to make it better.  I also read 
> some where that it had a run time of about 45 seconds is that true. 
> i was going to re-make the primary coil on it so i could tap it at a 
> lower turn which i can't do now because of the way it is made.  I am 
> not sure on how to go about calculating the inductance since it is a 
> weird primary design.