Steven Mark`s TPU

[ronotte]

Hi Gustav22,

it's nice hearing from you. About your dilemma I fear I cannot be of help, this because me and Otto started this project almost independently soon after the dfro post, so each one of us did it using a slightly different criteria. In my case I used ALL 1 mm standard PVC isolated electrical wire for the 57 turns input coils.....the reason?   I already had it and I'd no time to buy other wires.

So if you want to experiment with CHORDS (I prefere major 4,5,6) just try using different wires i.e. thin wire for the top ring (were it goes the F3) and ticker wire for the bottom ring were it goes the F1.  Anyway I don't think you will find macroscopic different behaviour. In my opinion thick Litz wire (at least with 256 isolated strands...) still remain the best solution according to my past experience.

Have fun and plan a visit to my Lab: I'm waiting for both you & wife.

All the best

Roberto

[zapnic]

my hero
http://dailymotion.alice.it/video/x3wrzo_fabrication-dune-lampe-triode_tech

[otto]

@wings

yes, it looks like the TPU dont "want" to be "nice" with transformers. Yesterday I worked with my professional power supply connected to the TPU. A really big vibration.

@tosky

please without the O.U. I would never claim O.U.!!!
I only said that my TPU feeds the grid and lights a bulb because I saw it.

I already posted that I want to use something like EM (again, thanks EM) did in the micro TPU thread. A little "TPU" drives the 6" TPU. How to make it I really dont know in this moment. For sure I know that the battery I want to use must be rechargeable and for sure I know that this battery is only used in the starting sequence of the TPU and then disconnected. Like in our cars.

Its only my "logic". Maybe Im wrong but we will see.

I still have my flash unit from a camera!!!

Otto

[otto]

Hello all,

maybe you guys know ths already but I want to post it.

When we connect the TPU to our MOSFETs something "strange" can happen: at a little input current from your power supply, less then 2A it sometimes happens that your MOSFETs or at least 1 of them is OVERHEATING!!!

I have this "problem". No, for me its not a problem because I know why it happens: a coil or coils are connected WRONG!!!!

Yesterday I was again reading dfros post: vertical coils (feedback) connected in series!!.....

I have his statements on a paper when Im working with my TPU but I connected the input coils in series....veeeery "clever"!!!
what to say? S..t happens!

His vertical coils are, I hope, the feedback coils.
His input coils are the control coils, I hope.

When I posted my drawing I said that its not the best solution....

This weekend I have enough time to connect all my coils in a better way.

Otto

[ronotte]

@all,

what you see is my consolidated TPU V10-7 builded according to dfro suggestions and Otto's posted schematic.

During the first preliminary test just to verify again all the connections and control about the correct wire polarities I verified that the TPU itself do remain always at ambient temperature for all input conditions. On the contrary even if using 2 microsec pulses the Mosfets do get hot when using more than 12V and specially the 245KHz......so attention is still necessary in order to avoid the mosfet's thermal run-away.  Best practice is to always use the current limiting PS feature in order to preset at a suitable level the max allowable current. In that way you can safely test with 20 or more Volt and still run with current limiting set to for example 2-3A...so saving your mosfets.

On the pic the TB connections are:

- on the 6 prong TB you find the 3 freq connections

- on the side left 1prong TB you finf the Ground connection

- on the 2 prong left TB you find the load connection


On the TPU main body, starting from left you find:

- two vertical TBs where the on the left TB are the mobius 6 (3 x 2) return wires, and right TB are the 6 mobius start wires

- 1 vertical TB with the start-end wires for each  'Input coils'

Robertoi