Re: Air Gap MOT Reactor

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "G by way of Terry Fritz <twftesla-at-qwest-dot-net>" <bog-at-cinci.rr-dot-com>

>By the way, some worry about MOTs not being able to withstand high voltages
>across the secondary.  I think they are good for 10 KV or so.  They have to
>be insulated well enough to not break down when power turns off at the peak
>AC voltage and the magnetic field rapidly collapses, generating more than
>the usual 2 KV  steady state output.  I have run 9 to 10 KV DC into a MOT
>charging reactor with no signs of breakdown.  Remember, the charging reactor
>nearly doubles the DC supply voltage so one doesn't need more than about 10
>KV DC to charge the tank cap to nearly 20 KV.
>
>I would be interested in hearing of others trying gapped MOTs as cheap
>charging reactors.
>
>--Steve

One point on the breakdown voltage- unless the core is grounded, the 
only voltage I think the insulation would have to withstand is the 
tank RF trying to jump across the inductance. The de-Qing diode 
should help with this. At DC, I don't think the windings would have 
any voltage to the core at all.

I am picking out a MOT to use as a choke right now, and as soon as I 
find enough diodes, I am going to try full wave rectifying my mot 
power supply, then passing the doubled output through the de-q diode 
and choke to the tank.

One question- Richie shows the DC charging circuit connected across 
the tank cap, not the spark gap. Will this configuration reduce the 
tendency to power arc? With the charging choke and diode blocking RF, 
do we still need to be concerned about the current oscillations 
Terry's NST research found? It would be nice to set the charging 
circuit inductance with the choke alone, without having to take into 
account the primary coil. The primary inductance may adversely effect 
the inductive-kick of the choke (not sure about that one yet!)

good luck!
Gregory