Tube Driver Help...please

[Pierre]

Hi !!!
I just finished GGG's Tube Driver clone and it doesn't work, i have allready checked all solder joints, all components values and all connections and nothing seems to be wrong, but the thing is dead, pots do nothing and i even got no hum when the effect is on. There is some "light" in the tube, a Sovtek 12ax7 WA...Is it possible that there's something wrong in GGG's layout..?
Thank you !!!

[rantony]

Hi man,

Make another one and use the layout that you can find in the following thread:

http://www.diystompboxes.com/smfforum/index.php?topic=44779.msg326159#msg326159

[Samy]

The GGG layout it´s correct, i have build one and it works, the problem with that layout it´s the "huuummm" noise problem and there is small note warning about that.
You can check the new layout that is floating around that i also buid and it´s working fine withou any noise problems.
You can try also the Musikding.de layout, i never tried it but i´m almost sure that it´s Ok.

[aron]

Pierre,

Debug it. This is the perfect time for an audio probe.

Aron

[the_random_hero]

The GGG layout it´s correct, i have build one and it works, the problem with that layout it´s the "huuummm" noise problem and there is small note warning about that.
You can check the new layout that is floating around that i also buid and it´s working fine withou any noise problems.
You can try also the Musikding.de layout, i never tried it but i´m almost sure that it´s Ok.

Have you tried shielded input and output conductors, converting the heaters to DC and star grounding? That should get rid of most of your problems.

[Samy]

The GGG layout it´s correct, i have build one and it works, the problem with that layout it´s the "huuummm" noise problem and there is small note warning about that.
You can check the new layout that is floating around that i also buid and it´s working fine withou any noise problems.
You can try also the Musikding.de layout, i never tried it but i´m almost sure that it´s Ok.

Have you tried shielded input and output conductors, converting the heaters to DC and star grounding? That should get rid of most of your problems.

I have used in both TubeDrivers shielded wire on the input and output but not used DC heaters.
The new layout made by finkfloyd works fine but i don´t know why it seems to me that the TD is very trebly, the tonestack it´s not very versatile and the output signal it´s very low, i have to use the vol pot always at max and even so, it´s not enough. I don´t know how the original is ... I have checked everything and it seems all ok and the sound quality it´s excellent.
I will try this month building the Musikding.de layout to ear the differences.

[rantony]

Can I have a direct link to the 'Musikding.de layout' ?

Thx

[Samy]

http://diy.musikding.de/content/view/30/8/

[Pierre]

i must have done something wrong because i cant make it work right, or maybe the tube is damaged, i don't know, i guess i will try building the Musikding one...
anyway, thank you all !!!

[Pierre]

I was looking at Musikding project and there's something I don't understand about the power supply, apparently it requires a 2 x 12V transf. (12V - 0 - 12V)...is this correct? In GGG's project power supply is 12V AC...I don't know, I'm confused...can somebody tell me what transformer do I have to use..? (and how many mA...)
thank you !!!

[the_random_hero]

Notice how in the GGG layout, the 12VAC signal is only half-wave rectified to roughly give + and - 12VDC? On the Musikding layout, they are using a centre-tapped transformer that is bridge-rectified to give you these voltages. Another huge difference is that the GGG layout is feeding AC to the the heaters (and therefore requires 12.6VAC).
The Musikding layout is feeding them with DC that's had a dropping resistor added to lower it to approximately 12.6VDC.
From everything I've seen, you should be using a 12VAC transformer which is capable of supplying at least 800mA (300mA for the heaters and a lot of headroom). This should keep you out of problems. If you get a transformer with CT secondaries, you could just use the Musikding layout for the power supply.
I really do suggest that you use DC on the heaters though. On some amps like the EVJ, this was one reason that the amps had so much 60Hz hum.

[rantony]

I was looking at Musikding project and there's something I don't understand about the power supply, apparently it requires a 2 x 12V transf. (12V - 0 - 12V)...is this correct? In GGG's project power supply is 12V AC...I don't know, I'm confused...can somebody tell me what transformer do I have to use..? (and how many mA...)
thank you !!!

The Musikding project uses a 24V C.T. transformer.