GTFO - A true valve high-gain overdrive

ezugaru · Post by **ezugaru** » 22 Mar 2012, 13:41

I am going with the donuts ... they are at the end cheaper xD, since if I dont buy mouser 40 usd at least, they charge 30 USD for the shipping since they use FedEx and not USPS, same with Digikey ...well .. I'll start in about ... 20 days

Niksounds · Post by **Niksounds** » 23 Mar 2012, 11:11

I don't have understand the question on heaters.

Do you use two alims inputs? one for 18v and one for 12v?

Or ?

phatt · Post by **phatt** » 23 Mar 2012, 11:21

Most of these ideas work by taking filament voltage from the 12 Volt DC plugpak/wallwart directly,,,
Then the same 12VDC is used to drive the DC/DC converter circuit which then delivers the high voltage for Valves.
at 12 volts the heaters only draw 150mA for one AX7 and the HTV only needs to be a few mA,, maybe 10mA is plenty.
Hope it helps.
Phil.

Niksounds · Post by **Niksounds** » 26 Mar 2012, 07:31

Thank you

birgitay · Post by **birgitay** » 26 Mar 2012, 22:13

While on your way. I cem Greetings from Turkey. overdrive distortion, as well as those interested in scuba gtfo I had a great smps alone have a problem with the unit directly entegrei ne555 ne555 süremessiniz is the reason for this sudden peaks mosdur fetten as well as direct from high voltage to the tubes as well as tensions entegrei malfunction causes burns directly from there to the c ıcm555 tlc555 or necessary to use-that is mos. you so much trouble with just viewed

birgitay · Post by **birgitay** » 26 Mar 2012, 22:26

c1 c2 is not axial. ac signal goes from there to the original scheme and thus there is need to use non-polar capacitor .

phatt · Post by **phatt** » 27 Mar 2012, 01:45

@*birgitay*
We obviously speak a different language so I may have not understood what you meant.

From the best I can make out of the Photo. *Holy crap man you are going to kill yourself*

You have a mains powered socket on an Audio PCB with no EARTH pin connected. Leathal,, prepare to meet your God.

For those looking on,, NEVER EVER build this kind of circuit.

Use a plugpak/wallwart that is double insulated OR if you must have mains power on board then GROUND the Case.

If you are not sure????????Then STOP an go do some research

From one who tries to stay alive, Phil

DarkRain · Post by **DarkRain** » 27 Mar 2012, 09:08

As far as i can see this is the original PCB from soldano GTO.... i don't know man but this seems like you said ... a very bad ideea.

Best regards,
Gabriel Tudoran
Analog Sound

phatt wrote:@*birgitay*
We obviously speak a different language so I may have not understood what you meant.

From the best I can make out of the Photo. *Holy crap man you are going to kill yourself*

You have a mains powered socket on an Audio PCB with no EARTH pin connected. Leathal,, prepare to meet your God.

For those looking on,, NEVER EVER build this kind of circuit.
Use a plugpak/wallwart that is double insulated OR if you must have mains power on board then GROUND the Case.

If you are not sure????????Then STOP an go do some research

From one who tries to stay alive, Phil

phatt · Post by **phatt** » 27 Mar 2012, 13:11

Hi Darkrain,
I'm not sure what I'm looking at and I'm not the expert here but ,,, *IF* that is a mains socket powering a board mounted transformer
(with exposed terminals ouch) then you may have mains potential on a circuit board whose only path to ground is through your guitar cord.

I've not yet read where Guitar cords where considered a safe ground path.

I personally would never dream of building such a device. I'd want to see the mains OFF the main circuit,, plugpak.

Hopefully someone with better knowledge of this gear can shed light on this.
Phil.

Luke650 · Post by **Luke650** » 27 Mar 2012, 15:30

Jesus, that looks dangerous.
I'm not sure about the job of the transformer. Does he works with 230V to 12V? Or 230v to 230V or higher? I found another pic of an original GTO.

ezugaru · Post by **ezugaru** » 27 Mar 2012, 15:36

I think that @birgitay is trying to say is that the're is a problem with the NE555, seems that his circuits just burnt in the PSU stage, maybe that's why he is supplying with a transformer direct in the pcb. In the second post he says that the C1 and C2 in the main circuit shouldn't be polarized since the AC voltage goes from the PSU to the original circuit so thereb shouldnt be any need of polarizd caps. *UNVERIFIED* xD

The pics he posted seems to be the original Soldano GTO, so the ground problems are factory xD

Groovenut · Post by **Groovenut** » 27 Mar 2012, 15:56

Luke650 wrote:Jesus, that looks dangerous.
I'm not sure about the job of the transformer. Does he works with 230V to 12V? Or 230v to 230V or higher? I found another pic of an original GTO.

IIRC the GTO takes mains voltage and converts to 12V heater and 350V(or so) B+ using the transformer. So the transformer is isolating the circuit (and the user) from the mains. Both the heater and B+ are then rectified and filtered. I dont know exactly why the earth is chosen to be left out at the input of the transformer, but a lot of commercial gear is earth isolated with transformers. Maybe not this high of voltage though. Even most wall pack power supplies only use hot and neutral from the mains, connect to a transformer and rectify/filter the stepped down voltage. I am sure it depends on what class the power pack is as well.

I am sure there is a good reason why the safety ground was left unconnected. Mike Soldano is known for building very solid gear.

Luke650 · Post by **Luke650** » 27 Mar 2012, 16:43

Thanks Groovenut.

@birgitay: Write your problem entirely in Turkish, maybe we can translate it with Google.

birgitay · Post by **birgitay** » 27 Mar 2012, 18:51

Teşürler kimse anlamaz diye türkçe yazmak istemedim herkese selamlar bu arada kendimi tanıtmadım bu sitede çok güzel paylaşımlar var herkesin eline sağlık öncelikle ben , TÜRKİYE'DE kimseyle bilgi alış verişi yapamıyorum uygulayan kişi çok az . Şimdi yukarıda yazdıklarımdan anlaşılmamış öncelikle smps katından söz edelim ; orada entegreden direk ırf740 yada herhangi bir mosfeti süremessiniz direk mos çıkış olduğu için transistörden gelen parazitler entegreyi bozar . Bu sebeple orada c-mos entegre yani ıcm7555 yada tlc555 lullanmanız gerekir . Ben soldano vede bir kaçtane kendim distortion yaptım fakat aleminyum kutuya koyunca problem çıkıyor kendi yaptğım anfilerde var uğultu son derece abartı dip ses var . BUyüzden araştırdım vede en iyisi saç yada prinç kutuya koymak denemedim ama deneyen varmı bilmiyorum ? Sonrası soldanonun j201 n-fet transistörlerle emitasyonunu yaptım gayet iyi çalıştı ama dip gürültü olduğu için bu tarz çalışmalar aleminyum kutu değilde saç kutu istiyor olabilir. bu konuda bilgisi olan varmı? uygulayan varmı ? Birazdan dr. boogie'nin tüplü distortionu resimini koyacağım ....şek

Ihunda · Post by **Ihunda** » 27 Mar 2012, 19:20

Here's the google translate, have fun:

Greetings to everyone he did not want to write Turkish Teşürler no one understands the way into the hands of everyone I have tanıtmadım health priority shares on this site I have a very nice, very few people practicing in Turkey can not exchange information with anyone. I have written above, let us speak now understood, first floor of smps, there is a MOSFET is integrated directly süremessiniz ırf740 or any direct mos transistors for the output from the parasites that infects entegrei. For this reason, there must be c-mos integrated so ıcm7555 or tlc555 lullanmanız. Distortion as well as I did myself a Soldano: Here I am, but aluminum box Lecture to carry on your card has its own problems out there buzzing sound extremely exaggerated dip. Worth thinking as well as the best researched in the box to put the hair or brass do not know Have not tried, but trying to? After n-fet transistor soldanonun j201 emitasyonunu because I worked very well, but this kind of background noise studies may want to box, aluminum box, not the hair. with knowledge of this subject here? apply here? Soon dr. Boogie put tube distortion picture, fig ....

DarkRain · Post by **DarkRain** » 27 Mar 2012, 19:39

There is a known problem with the GTO unit that was accepted by users/factory - don't know any much details but i heared about it some time ago. The GTFO design was made with 2 things in mind: one is the size and the other one the supply is at a non lethal voltage - anything that would happen would stay in the box (and at that current there are not so much things to happen). If you use the mains to power a tube pedal... that could be a problem if is not designed right.
@birgitay: this is not the original GTO design - GTFO design is using a SMPS to generate high voltage and not a transformer.

Best regards,
Gabriel Tudoran
Analog Sound

ezugaru wrote:I think that @birgitay is trying to say is that the're is a problem with the NE555, seems that his circuits just burnt in the PSU stage, maybe that's why he is supplying with a transformer direct in the pcb. In the second post he says that the C1 and C2 in the main circuit shouldn't be polarized since the AC voltage goes from the PSU to the original circuit so thereb shouldnt be any need of polarizd caps. *UNVERIFIED* xD

The pics he posted seems to be the original Soldano GTO, so the ground problems are factory xD

birgitay · Post by **birgitay** » 27 Mar 2012, 19:42

dr. boogie tüp distortion

birgitay · Post by **birgitay** » 27 Mar 2012, 19:44

DarkRain wrote:There is a known problem with the GTO unit that was accepted by users/factory - don't know any much details but i heared about it some time ago. The GTFO design was made with 2 things in mind: one is the size and the other one the supply is at a non lethal voltage - anything that would happen would stay in the box (and at that current there are not so much things to happen). If you use the mains to power a tube pedal... that could be a problem if is not designed right.
@birgitay: this is not the original GTO design - GTFO design is using a SMPS to generate high voltage and not a transformer.

Best regards,
Gabriel Tudoran
Analog Sound

ezugaru wrote:I think that @birgitay is trying to say is that the're is a problem with the NE555, seems that his circuits just burnt in the PSU stage, maybe that's why he is supplying with a transformer direct in the pcb. In the second post he says that the C1 and C2 in the main circuit shouldn't be polarized since the AC voltage goes from the PSU to the original circuit so thereb shouldnt be any need of polarizd caps. *UNVERIFIED* xD

The pics he posted seems to be the original Soldano GTO, so the ground problems are factory xD

Bilgin için teşekkürler fakat smps devresinde 555 entegresi yerine ıcm7555 yada tlc 555 kullanmak doğrudur

ezugaru · Post by **ezugaru** » 27 Mar 2012, 19:52

^ Thanks for the information, but besides the ICM7555 / 555 (SMPS) I used the right TLC.

birgitay · Post by **birgitay** » 27 Mar 2012, 19:59

ezugaru wrote:^ Thanks for the information, but besides the ICM7555 / 555 (SMPS) I used the right TLC.

Evet doğru olması gereken odur