I always have a problem getting horizontal streamers from this tesla coil. They are either hitting the floor, or more often than not hitting the ceiling.
This secondary has suffered several incidents of damage, either from primary arcing or streamer hits (see below for Cambridge damage) This may be because I no longer have a strike ring as on previous coils.
The removal was because rather than protect, it seemed to attract streamers even more, I will however soon be adding an earthed wire around the periphery on the underside of the Acrylic sheet that protects the primary.
After the damage above had occurred, I repaired the secondary by loosing a few more turns, which takes it down now to about 1394 turns from the original 1400.
I also raised the secondary to reduce the coupling and give more clearance between the inner turn of the primary and the secondary. The topload was also lowered by an inch to provide more shielding.
The effect of both these moves has resulted in no more secondary damage even after a few protracted runs.
For More Photos of Nottingham Gaussfest 2010:
Goto the organisers site
My eight inch coil running on my PDT (Pig)
Cambridge 2009: 6kW~
This was running with a blown static gap. Shortly after this I changed to a 200 bps synchronous rotary.
The Cambridge (UK) 2009 Teslathon was held over the last weekend in October at the Cambridge Museum of Technology.
Despite a disappointing performance on the first day, the coil performed very well on the Sunday.
The improvement was basically down to the fact that I managed to get the coil tuned properly overnight, and also the loan of a better static spark gap, (thanks Phillip).
It is possible to get good performance from a pole distribution transformer (PDT) even when just using a static gap rather than the normal RSG (be it an ARSG or SRSG variety).
Power is between 5 to 6 KW.
The MMC value is 64nF which with my ballast of 130.8H (secondary side equivalent value) is very close to resonance at the mains frequency 50Hz (UK).
It was not all plain sailing at Cambridge however, as on the first day I had a rather nasty strike to the secondary, but it was not until I got the coil home that I discovered it. I found that the bottom two turns of the secondary had become fused together after the strike. However I was very lucky with the location of the damage as the repair was fortunately quite simple. The original 1400 turns have now simply become 1398.