I am very sorry for how much I worked and for the amount of money I spent.
I have no joy in this project and no one is willing to help me concretely on this forum.
With the exception of the Captain and Coonw
I have no joy in this project and no one is willing to help me concretely on this forum.
With the exception of the Captain and Coonw
@RICHARD877

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You have a string of non English posts that have not been approved.
Please read and follow the site rules:
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This is the driver schematic I am using, this works well. I drew this by reverse engineering the Ares Audio PCB. Also attached is the way i have connected The 6C33's, It took me several attempts to get to this drawing, as there is much conflicting information on the internet. The Ares Audio Drawings have quite a few mistakes, I currently only have 4 output tubes so i only populate, either 2 tubes left and right or 4 tubes mono. I have tried both 2 and 4 tubes and all works great.Captain, I noticed that in Tim's diagram the pins of the 6C33C tubes are numbered differently than what I found on the net, how did you identify how they are connected?
I was just wondering, you have just one transformer (in Picture) is this HT and filaments ? What windings does it have ? I think you need separate filament supplies for each tube, I am using 4 Output tubes per channel, my heater transformer has 4 x 12 volts @ 9.5 Amps (enough to power 2 tubes) so if you look at my tube wiring diagram you will see that it is ok to power the two upper tubes from one winding and the two lower tubes from another. But i don't think you could power one upper and one lower from the same winding, as the the center tap of the filaments (cathodes) are at different potentials. Are you using separate supplies in your design ?

This is an English language forum. Please do not post in a language other than English.
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Would you me sell a mono Amp?Captain, I noticed that in Tim's diagram the pins of the 6C33C tubes are numbered differently than what I found on the net, how did you identify how they are connected?
Gruß
Richard
I greet you with respect, Captain. So, the transformer for the + and - 150 v rails is visible in the pictures.I was just wondering, you have just one transformer (in Picture) is this HT and filaments ? What windings does it have ? I think you need separate filament supplies for each tube, I am using 4 Output tubes per channel, my heater transformer has 4 x 12 volts @ 9.5 Amps (enough to power 2 tubes) so if you look at my tube wiring diagram you will see that it is ok to power the two upper tubes from one winding and the two lower tubes from another. But i don't think you could power one upper and one lower from the same winding, as the the center tap of the filaments (cathodes) are at different potentials. Are you using separate supplies in your design ?
The transformer for the 6C33C tube heaters is separate and is located under the circuit with the rectifier and several capacitors (it can be seen a little in the picture).
The third transformer for the heaters V1 V2 and V3 is mounted under the circuit with the three tubes (it is not visible at all in the picture).
p.s. I respected Tim's project 100%.
Mario will greet all the members, and Mooly
is it working ? of course it did, this is a proven design...this amp eats 400 watts of power...we displayed this in a Dusit Hotel audio show setup...way back in November of 2017
Attachments
I follow for years this thread now I am ready to build this OTL, still waiting for some material and the tubes from Ukraine, I will of course post soon progress in this project, I will follow the Tim's design 100% without change anything, I will just add a soft start module for the AnTek Toroidal transformers and the suggested speaker protection module, regards for all members here and thank you for all information given I will do the same
Hi Mario, I am really sorry for the problem you having with this project, I will see also myself soon facing difficulties in this built, one things I suggest to you is to start over and do not use any PCB, I build many tube amplifier and encounter problem with diy PCB, so just start all over and use point-to-point wiring, that keep the project simple and easy to find problems....all the bestI am very sorry for how much I worked and for the amount of money I spent.
I have no joy in this project and no one is willing to help me concretely on this forum.
With the exception of the Captain and Coonw
Hello, it works normally, with the team you have next to you, it's normal.my OTL build....
But I am alone at home😡
Hello Kissabout, thanks for the advice. I made one mistake when I built the pcb, the capacitor C5 was placed wrongly.I follow for years this thread now I am ready to build this OTL, still waiting for some material and the tubes from Ukraine, I will of course post soon progress in this project, I will follow the Tim's design 100% without change anything, I will just add a soft start module for the AnTek Toroidal transformers and the suggested speaker protection module, regards for all members here and thank you for all information given I will do the same
it is mounted on the grids of the tubes v2 and v3 pins 1 and there is a negative voltage. so this capacitor is placed with the plus on the GND. do not make this mistake as smoke comes out of it. I saw this aspect too late and continuing to I feed the amplifier for adjustments and measurements, probably one or more tubes or burnt.
Greetings to all members.
today I built a preamplifier with the EF86 tube.
What do I use it for?
To check these tubes because I did not find what defect my OTL has.
Now I ask all members on the forum; Is there any simple scheme with 6C33C?.
There must be a possibility to check these tubes without a cathometer
today I built a preamplifier with the EF86 tube.
What do I use it for?
To check these tubes because I did not find what defect my OTL has.
Now I ask all members on the forum; Is there any simple scheme with 6C33C?.
There must be a possibility to check these tubes without a cathometer
Mario, from your posts, it looks like you don't know much about tubes. You built a preamp and you don't know what to do with it?
You are trying to build an OTL which is the most difficult project you could choose. 6C33C is a headake of itself.
You should have started with something more simple, like EL84 single ended, and then go slowly into more complicated staff.
What is cathometer? Does it have anything to do with collider?
Sorry, no offence, but you got to know how to use common test equipment, and what to test and what to expect.
You did not want to invest into transformers, but instead, you spend enormous time and frustration into something you cannot accomplish,
and there is no one who can help you. You got to have some basic knowledge to start with.
You are trying to build an OTL which is the most difficult project you could choose. 6C33C is a headake of itself.
You should have started with something more simple, like EL84 single ended, and then go slowly into more complicated staff.
What is cathometer? Does it have anything to do with collider?
Sorry, no offence, but you got to know how to use common test equipment, and what to test and what to expect.
You did not want to invest into transformers, but instead, you spend enormous time and frustration into something you cannot accomplish,
and there is no one who can help you. You got to have some basic knowledge to start with.
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