• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Made a new tube amp, 6J5 +27 +45

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Yes...I use caps with about 2 time more voltage limits /and also brands make caps with more limit that is shown/ and I don't use my amps to work all the time on full power that input signal will go direct and cathodes AC are max., I think You don't like this mode also.
Good and cool listening this amazing tube!

You are quite right. Usually do not enter such a high level. I think it needs to be so high capacitor voltage margin.
2 times the negative cathode DC is definitely impossible. At least I think that would be enough.
 

Attachments

  • B1.JPG
    B1.JPG
    111.5 KB · Views: 137
  • B10.JPG
    B10.JPG
    86.9 KB · Views: 24
  • B9.JPG
    B9.JPG
    86.7 KB · Views: 34
  • B8.JPG
    B8.JPG
    101 KB · Views: 20
  • B7.JPG
    B7.JPG
    103.3 KB · Views: 20
  • B6.JPG
    B6.JPG
    103.6 KB · Views: 26
  • B5.JPG
    B5.JPG
    124 KB · Views: 126
  • B4.JPG
    B4.JPG
    117.3 KB · Views: 124
  • B3.JPG
    B3.JPG
    163 KB · Views: 133
  • B2.JPG
    B2.JPG
    103.8 KB · Views: 130
Beautiful job - I like your use of a thick piece of Al for the chassis. The finished amp is gorgeous, especially with the globe shaped tubes!

-Pat

Other globe tube.
 

Attachments

  • B16.JPG
    B16.JPG
    77.7 KB · Views: 29
  • B15.JPG
    B15.JPG
    124.7 KB · Views: 27
  • B14.JPG
    B14.JPG
    102.1 KB · Views: 27
  • B13.JPG
    B13.JPG
    158.4 KB · Views: 29
  • B12.JPG
    B12.JPG
    91.6 KB · Views: 23
  • B11.JPG
    B11.JPG
    166.1 KB · Views: 28
  • B17.JPG
    B17.JPG
    91.3 KB · Views: 24
That is a very good looking and well built amplifier. I wish I could take a listen to it, you don't usually see such a tube combination. Will you be taking measurements and sharing them? I am really curious how an amp using tubes from 80-100 years ago measures.

Oh! You are very welcome to listen. But you and I apart thousands of miles away ah. If you really want to hear. Always welcome to come to China, I will warm hospitality. Can not underestimate these centuries old goods, but it is far from any offspring tube unmatched.
The measurement data of the machine as follows:
-1db 15Hz-46kHz
Ringing frequency: 120kHz
Distortion: 6% 2w (estimated)

Output transformer parameters:
Primary Inductance: 25H
Leakage inductance: 21mH
Impedance: 4600:8:4
Primary: 2900 turns

All transformers are my own wound.
What argument can also feel free to ask me.

Fortunately, there is the DIY CNC winding machine.

Test instrumentation is: oscilloscopes, signal generators, millivoltmeter.
 
You can also do so one out, texture, and very pretty. It is important that the surface treatment of the aluminum plate. If you are willing to do so, there are difficulties, you can contact me.

My main difficulty is my lack of a Bridgeport (milling machine). I'm hoping to get my paws on that missing piece of equipment at some point in the not TOO terribly distant future, though. :)

-Pat
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.