Photo Gallery

[male42]

blue glow. this is a consequence not a complete vacuum in the tube

 

[Wachtfels666]

There are no LEDs used. The glow is natural for some types of tubes, but i don't know the reason for it.

In my picture the blue glow is very bright thanks to long exposure. In reality it is not as bright as in the picture.

 

[Refugee1]

Surely the blue would be inside the anode if there was air in the tube.
I had an EL37 go to air and the blue could be seen through the mica at the top of the anode. I kept it and after a few months the gettering started to go white and later faded.

 

[mhouston]

Lots and lots of tubes glow like this. I have 807s, TJ 300B carbon plate limited editions which glow like this and earlier KT88s which did the same.

 

[regiregi22]

Sorry, i was not sure about the correct name. It is an russian type of the 5U4GB, it is called 5U3C.

I though the same, 5U4GB doesn't have those cathodes...

 

[rfengineer2013]

Is the blue effect on the KT88 obtained using blue LEDs on the background?

More likely it's glow from the glass caused by electron-impact. Note the stack of three circular blue glowing areas in front of the 3 holes where you can see the glowing filament. Streams of electrons exit through the holes and strike the glass causing the glow. Such a glow is usually very low-intensity, brought out in the photo by the long exposure as mentioned by the OP.

Gas in the tube would cause a much more dramatic glow.

 

[DHT2009]

My 345 SE Amp

All DHT 180/112A/345

 

[tomchr]

Love the globe bulbs! Nice wiring job too.

~Tom

 

[DHT2009]

Love the globe bulbs! Nice wiring job too.

~Tom

Thank you Tom

 

[DHT2009]

EC86/EL34SE

Very long ago that I do not come here.

 

[mhouston]

DHT2009: very good work. Very neat wiring. Love the old balloons. This is my attempt with some 1920s UX-171A.

retro-thermionic: "Intermezzo" - 1920 UX-171-A power amp

 

[DHT2009]

DHT2009: very good work. Very neat wiring. Love the old balloons. This is my attempt with some 1920s UX-171A.

retro-thermionic: "Intermezzo" - 1920 UX-171-A power amp

thank you mhouston , I love the balloon tube as well and Your amp is pretty good as well. For 71 balloon tube I ever make preamp.

 

[mhouston]

thank you mhouston , I love the balloon tube as well and Your amp is pretty good as well. For 71 balloon tube I ever make preamp.

How many watts does yours make? Mine is about 0.5W.

 

[DHT2009]

How many watts does yours make? Mine is about 0.5W.

It is not a power amplifier but it is a pre-amp.

 

[maxmekker]

My latest amp.
Based on Mullard with some twiks.
Output is 34W@8ohm.
EF86, 7025, EL34B and EM84
Trafo TU29

Made a modell in SolidWorks before I started with the build.

 

[overtheairbroadcast]

My latest amp.
Based on Mullard with some twiks.
Output is 34W@8ohm.
EF86, 7025, EL34B and EM84
Trafo TU29

Made a modell in SolidWorks before I started with the build.

Looks ABSOLUTELY NOTHING like the Solidworks mock-up (the wood grain is close, but not the same) and because of that, I will offer to buy it from you for $25 USD.

Include shipping and I will bear the hardship of looking at such a thing of beauty.

That is awesome work. What does the underside look like?

 

[tim614]

Why the round can. What's it for?

 

[maxmekker]

Why the round can. What's it for?

Power transformer, the "can" is made of solid block of aluminum

 

[dady]

And the tranny behind the bunker?

 

[dady]

Looks good! But You You took many solutions for non-existent problems, I will try this Solidworks mock-up software, Does is friendly or/and intuitive?
Best Regards.