100 watt Tube Amplifier

[DRNB]

Beautifull work Mr Mars!!!

[Gerhard]

...didn't know you could keep steel in the austinitic state...

Ja, otherwise the "Man van staal - Steve Austin" would have plakked to any ol' magnet

[Mars]

Wow-great work.  Any chance of a write up on how to construct a transformer and where to source component parts?

I have started a thread on DIY Output Transformer design in this forum. See you there

[Mars]

Here is a few more pics of the underbelly:

I wired up the transformers and the cathode resistors so I could check the power supply. My wire colours were a bit confusing, so I pre-wired the transformers to avoid confusion/electricution









Voltages seems to be on target (note this is off load voltage)

[iondb]

Cool.  Nice going.  The amp is looking good.

[Family_Dog]

Karel, what DC voltage are those filter caps rated at? 


-F_D

[Mars]

The caps are Roederstein 220uF rated at 450V. I put them in series - so the headroom of 900V should be safe for the 600V DC.

[Moog]

I feel that we should promote our local industutry wherever possible. How far are you with your design. Please update us on your challenges and success.

[Mars]

Hi Moog

I am busy reconfiguring the pre-amp section. I have to choose to go for 6SN7 DC coupled pre/long tail phase splitter, or a noval option (EF86/ECC99).

The high voltages available makes 6SN7 option look attractive.

So the chassis will be redesigned. Slight layout change with a small choke under the 'hood. The project is going slow, while I am churning out repair jobs, but I hope to get into it in the winter.

[jvdrijst]

Hi Mars,

Any indications on what a this amp in kit form would go for?

Thanks

[Hi-Phibian]

Having heard a few 6sn7 pre amps I would go that way but good exotic ones were once cheaper then ECC types but in the last decade or so it has become very popular and nice NOS costs plenty now too.

[Mars]

Any indications on what a this amp in kit form would go for?

You can PM me for a quote