Derby Teslathon 2003

Venue : Nunsfield House Community Centre
Location : Alvaston, Derby
Date : 23rd/24th May

___This year's event was well attended, with 6 classic Tesla coils, several solid state Tesla coils, various other HV devices and around 40 high voltage experimenters from across the UK.

___Long time coilers Mike Tucknott & Brian Le Page showed off this latest version of their medium sized magnifier.
___The system was powered by a 15kVA 11.2kV pole pig, with an MMC type tank cap and a high speed rotary gap with series static gap. Mike and Brian are still working the bugs out of this setup and it's current 4 foot spark output is definitely just the starting point. Expect big things from these guys next year!

___Not content with organising the entire day, Martin Dale exhibited his venerable 4" classic coil, freshly re-wound after its untimely demise at last year's event.
___It was powered by an 8.25kV radar transformer, ballasted on the secondary side using a pair of large oil filled chokes, also sourced from an old radar modulator. The primary capacitor was a homebuilt 16nF stacked plate type immersed in mineral oil. Martin used his asyncronous series rotary at break rates of up to 800pps to great effect.

___Martin's system proved a solid performer throughout the day, consistently hitting grounded objects over 48 inches away.

___Dave Gamble brought along this large 7" Tesla coil. Unusually this system used a DC power supply, charging the 50nF tank capacitor to around 40kV through a pair of charging chokes. The system used a variable speed rotary gap, which in conjunction with the DC supply allows power throughput to be controlled without a variac.
___It also employed a remote tunable primary and remotely variable coupling coefficient, via a pair of stacked primaries mounted on leadscrews. On its day this setup can crank out sparks upwards of 6 feet long, however Dave was having some trouble with the home made charging reactors, which limited him to comparatively low power levels.

___Colin Heath's newly rebuilt 6" coil put on a fine show, regularly striking out to more than 60".
___Colin's coil was powered by a 10kV 300mA transformer, charging a 75nF tank capacitor, made up of a 50nF pulse cap and a 25nF MMC. The system was commutated by a 400bps asycronous rotary spark gap.

___Steve Conner brought along this small DC Tesla coil, which cranked out wildly flailling 30" sparks at over 500bps.
___This coil is particularly unusual, as the complexity of a DC resonant charging topology is normally reserved for systems in the 25kW + range. It used a single microwave oven transformer, with a voltage quadrupler, driving the MMC tank cap through a charging reactor made up from tube amp smoothing chokes, to achieve a firing voltage of around 20kV. The tiny rotary spark gap was made from parts salvaged from an old harddrive.

___Steve also brought along his ground breaking Off-Line Tesla Coil. This solid state masterpiece was one of the most unique exhibits of the day, being only the second of its kind ever built.

___Alan Sharp, organiser of the long running Corby Teslathons, made the trip down from his new home in Scotland to demonstrate this unique Quad Solid State Tesla Coil.
___Sparks jumped diagonally between the four coils in alternate opposing pairs, and then between adjacent coils. Naturally this was set to music, provided by audio modulation of the sparks themselves.

___Mike Harrison showed off his Jacobs-Ladder-o-phone, a unique Jacobs ladder featuring a horn on the top to channel the sound of the arc out towards the spectator and a mirror in the horn to give an head on view of arc climbing up the rails.
___To the left of the photo you can see part of Mike's 500kV marx generator. This used 20 stages charging to 25kV and then triggered via a Sulfur Hexaflouride insulated relay, with sparks regularly hitting over 24".

___Mike also brought along his electromagnetic can crushing rig, the Desruct-O-Tron. It uses several pulse discharge capacitors salvaged from surplus medical defibrilators discharged into a small air cored coil to produce an intense magnetic pulse which crushes the cans.

___Teslathon regular Richie Burnett brought along his trusty Solid State Tesla Coil, making it's third Teslathon appearance.

___James Riggs demonstrated this neatly packaged Solid State Tesla Coil producing sparks up to 12" long.

___James' coil's consistent high RF output made it ideal for lighting a variety of gas discharge tubes, broken plasma lamps etc.

___Derek Woodroffe brought along this neatly constructed micro coil. Standing less than a foot tall this was a true table-top coil. Power was provided by a tiny 6kV 20mA bug zapper transformer, with a miniture MMC capacitor and copper pipe spark gap to match. Awww ain't it cute!

___Phil parry brought along his 'Bodger's Delight' Vacuum Tube Tesla Coil. Unfortunately he hadn't quite got it finished in time for the this event...

___Pictures by Mark Hales, Phil Parry, Paul Benham and Steve Conner.

___Words by Nick Field