The Shaka tube http://www.diyguitarist.com/DIYStompboxes/ST

[musicrob279]

Can any one tell where I can find the schematics to this project.
I'm having major problems but seems to be in order.If you build this and got it to work please help thanks.

[RDV]

RDV

[radio]

Nice scetch

How about this one I would not start without his enclosure pics

http://www.diyguitarist.com/DIYStompboxes/ST1590BB.htm

JME

[aron]

Now you can use the EH Tube box and have a double Shaka Tube in a box!

[musicrob279]

I got the darn thing wired up but it is not working I have to go over the whole thing.Thanks for the schematics.

[musicrob279]

Are those BP caps for the 22uf and the 2.2uf or should they be polorized.
Can I use 250k Pots for the gain controll
What will be the differents if any.
Thanks

[aron]

22uF and the negative side towards ground.

Yes, you can use a 250K and it will have lots more drive than the 100K.

Aron

[george]

Hey Aron

ever considered reverse-engineering your Mini Boogee (been out of production for a while now  :wink:) ?

Or could we achieve the same thing by replacing the op-amp in the ST with another valve (tube to you US folks).

We could call it the Shaka Tube Tube, or the Shaka Double Toob, or even the Mini Shaka Toob Boogie ...

then we could model it in JFETs :lol:

[musicrob279]

I am at a loss why am I getting 6v on pins 4 and 7 of the tlo71
I am using a 12vDC 850ma walt wart is this not enough power
Does it have to be 12vAC.I hear the good sound but it sound like
it dies like a gated action.Very good sound then it make a splatter
kind of a sound and cuts off.Arn't I supposed t get higher readings
on the V-V+ and bias.Does the ground of the power supply get connected to the ground of circut board.Does pin 5 of the tube go to board ground.
Thanks for help so far it almost works.

[Paul Marossy]

Pin 5 of the tube should go to ground. I'm not sure why you are reading 6V at pins 4 & 7 of the TL071. Kinda strange... are you sure that you have the voltage doubler circuit wired up correctly? Something is screwy.
And yes, you do need 12VAC for it to work. 850mA is plenty of current available for the tube heater. The gated sound is definitely due to the whacked voltages at the opamp.

I hope you get it working. I built my Shaka Tube per that exact PCB layout (that I created) and it works great.

[musicrob279]

So your saying my 12VDC 850ma won't work.
So I'm not clear does the ground of the circut board
and the voltage doubler get connected together.
Something is screwy. I must divide and conquer.

[Paul Marossy]

No, I was trying to say that your 12VAC 850mA supply is adequate. All grounds must connected together for it to work properly...

[musicrob279]

Well my wall wart says 12vdc not 12vAC but is it adequate.
So the ground from the power supply gets grounded to the board
and the the tube is this correct.
Thanks

[Paul Marossy]

If you are trying to power it with a DC wall wart, that is your first problem. The circuit needs an AC power supply for it to work correctly.

Second, power supply ground and Pin 5 of the tube is connected to the same ground as the rest of the circuit. All grounds are connected together. There is not a seperate power supply ground.

[musicrob279]

Will a 18VAC 1000ma be ok.

[Paul Marossy]

18V is too high of a voltage for the tube heater. It needs to be 12.6V maximum. Give it 18V and you're likely to ruin the tube and possibly the opamp. A 1000mA 18V transformer will put out considerably more than 18V with such a small load on the transformer.

A 12AX7 running on a 12V heater supply only needs 150mA of current. You could use a 300mA 120VAC/12.6VAC transformer to power the circuit temporarily until you get it working.