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6BG6-GA

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I purchased a few of the "super" 6BG6GA. Here is a photo of the "super" version (on the left) next to the version I have. The plates look identical. Can someone tell me what the 2 fins on top of the mica insulator are for?

I am now running my version in SE UL mode at 465V on the plate, 455V on the screen, at 73.4mA. About 30W dissipation. So far, so good.
 

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6BG6GA SE UL

Very simplistic circuit.

I had a PT with a 12.6 CT & 10V CT secondaries, so I wanted to make use of it. I know the 5AR4s are overkill in this application. I will ultimately use 5V4GAs as the rectifiers, I just don't have them yet.

Output measured at about 7.5W RMS

Scott
 

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Scott, did you do any 'in circuit' comparisons between the 'super' 6BG6GA you purchased versus the side getter version you already had? I was checking through a box of tubes from an old Ebay purchase this morning, and found I've got 12 of the 6BG6GA that are identical to your original ones (Sylvania, grey plates, side getters, screen grid radiators) so I'm curious if you concluded that they 'are' the super 6BG6GAs?
 
Both tubes run at the same parameters in my circuit. Comparing the plates of the two they are identical even down to the mica insulators. Only difference is apparently the side getter and screen radiators.

In case you didn't see the photo linked in post #8, you can definitely see the difference there.

Scott, did you do any 'in circuit' comparisons between the 'super' 6BG6GA you purchased versus the side getter version you already had? I was checking through a box of tubes from an old Ebay purchase this morning, and found I've got 12 of the 6BG6GA that are identical to your original ones (Sylvania, grey plates, side getters, screen grid radiators) so I'm curious if you concluded that they 'are' the super 6BG6GAs?
 
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Thanks for the response, Scott.
BTW, I did see the photo in #8. The 6BG6GAs I have look like the left hand image, with the side getters.
So, from what you're saying I may infer that the top getter 'super' 6BG6GAs are functionally the same as the side getter, big, gray, plate 6BG6GAs? If so, good news.
 
Yes. In my case there were no differences in the voltage or current readings between the two. No red plates. No performance difference that I can tell. I ran both versions at 475V like shown in the schematic I posted.

It is interesting though, that there seems to be an intermediate variety of these. When you compare the plates though, they are very different than the smaller "glossy" black plates in the original version.

Please keep me informed of your experience with these.

Thanks for the response, Scott.
BTW, I did see the photo in #8. The 6BG6GAs I have look like the left hand image, with the side getters.
So, from what you're saying I may infer that the top getter 'super' 6BG6GAs are functionally the same as the side getter, big, gray, plate 6BG6GAs? If so, good news.
 
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