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ArcticMyst Security by Avery

Vacuum Tube (Thermionic Valve) Fun!

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Hence why the triplle rectifier with 3 5U4Gs has more power and distortiin than this model.
 





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Awesome setup there Sig!! :beer:

Looks really good with those tubes and the soundtrack is pretty epic too :D

~ LB
 
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Seems to be working today. It kept going to that fuzzy screen and saying an error occurred.
 
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Bumping this thread as I have been bitten by the tube bug. I've been wanting to build a nice quality tube amp for a while; picking up some misc tubes here and there.

But this past weekend I hit up the Harrisburg Firecracker hamfest and in perusing the tubes from various vendors I was made an offer I couldn't refuse.

I now have tubes.
20140705_142136.jpg


I basically bought his junkpile (tubes that are not in high demand, oddities, weird heater voltages, etc) but there are a bunch of power 17DQ6B pentodes that are my likely candidates for the output stage of a moderately beefy amp.

Not bad for $30 I think.

Also breadboarding with tubes - made a super quick and dirty headphone amp but it sounds damn good, can't wait to start doing some stuff with the bigger tubes.

20140708_205744.jpg


Also trying my hand at 3d printing some tube sockets
20140706_162556thmb.jpg
 
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Awesome post, Mario!

That is an insane lot of tubes you scored there, very nice! Are they all tested good or is it a truly random smattering?

I've always wanted to build a wide spectrum linear amp from power triodes (with interchangeable front end filters to select band) but it is just way too expensive of a project to even attempt.
 
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I heard about something while watching a blog video from Chris Boden of the geek group the other day that I had no idea existed. Vacuum Tube Tesla Coils. Now I want one!
 
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Oh yes, VTTCs are magnificent. Our very own Ionlaser555 has built a few whoppers not too long ago. Construction is fairly simple but they're higher cost than SSTCs (but cheaper than DRSSTCs) and getting the grid leak circuit right is a finicky nightmare.
 
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Awesome post, Mario!

That is an insane lot of tubes you scored there, very nice! Are they all tested good or is it a truly random smattering?

I've always wanted to build a wide spectrum linear amp from power triodes (with interchangeable front end filters to select band) but it is just way too expensive of a project to even attempt.

Some seem new, the ones in the plain white boxes are probably used but all the tubes were supposedly tested.

I was disappointed there weren't any glowy tubes in the lot :p (no mercury or inert gas regulator tubes)
 
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I have ONE mercury rectifier, NOS NIB, that I'm wanting to make an amp with. It's an 866A, and I'm hoping it gives some blue.

I want to use that, along with two thoriated-filament (white glow) "pancake" tubes, that I've seen some other builds with but for the life of me I *cannot* remember nor find what those tubes were.

They were flat and oval, (kinda like squashed spheres) and had that signature incandescent white glow (filament-as-cathode). I believe they were top-cap takeoff, too.

Not sure if that rings any bells :p
 
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Nice collection there Mario :p , Thanks Sig : D , One thing about VTTCs is that they are hard to kill :p .

I found that getting the primary sorted was the main problem I had .

aryntha , did they have 2 pins at the top ( dual anodes ) and look like flying saucers ?

I found a picture of the "desk" amp I made with two magic eye tubes , sounded pretty good .

SAM_0965 by TwirlyWhirly555, on Flickr
 
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ped

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I loved those magic eye tubes.

Fascinated me as a kid.
 
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Be sure to get that old 866 tube hot before
you slip her the HV !!! The Hg must have time
to vaporize or the tube will flash back.
HMike
 
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Be sure to get that old 866 tube hot before
you slip her the HV !!! The Hg must have time
to vaporize or the tube will flash back.
HMike


Thanks for the info on that -- I wonder if I could put in some kind of time delay on the amp design.
 




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