[hpamdr]

I'm sure that's accurate
So you want the -23 - 0V input stage adjustment?

Yes !

 

[SonicTrance]

Yes !

You too @OctavianH ?

 

[OctavianH]

Honestly I do not really know what I can do with it. For what I want to use -10V grid bias is enough. What I can imagine is that having this will allow me to use some output tubes on the inputs. Is there any other advantage?

 

[SonicTrance]

Honestly I do not really know what I can do with it. For what I want to use -10V grid bias is enough. What I can imagine is that having this will allow me to use some output tubes on the inputs. Is there any other advantage?

No other advantage. The disadvantage is higher sensitivity on the adjustment.

 

[OctavianH]

No other advantage. The disadvantage is higher sensitivity on the adjustment.

Then no. I guess I am fine with 0-10V.

 

[OctavianH]

Guys, someone has to try these But of course, not me, need adapter and I am still in my "no adapter" mood.

 

[SonicTrance]

Guys, someone has to try these But of course, not me, need adapter and I am still in my "no adapter" mood.

They're very good tubes. I got a bunch myself. Basically they're half a 6SN7 with a grid and anode cap.

 

[UntilThen]

Reminds me of the 596 rectifier which I'll be getting.

 

[UntilThen]

EL39 are brand new in the box. So perfect like it just left the factory. Wonder what year it's manufactured in? Words on the base of tube says EL39-56.37 and on the box its says 11-56. Is it made in 1956? Grey paint is similar to the Philip Miniwatt EL3N red paint. I imagine the paint will fall off easily and then it will be ugly.

 

[UntilThen]

Next to the Sylvania 807. The 807 is better constructed. Thicker glass, gold plated pins. EL39 is kind of plain Jane apart from the paint. Both are brand new but one of the 807 took out my Elekit TU-8200.

 

[UntilThen]

RT EL39 and Telefunken EL12 spez.

 

[hpamdr]

EL39 are brand new in the box. So perfect like it just left the factory. Wonder what year it's manufactured in? Words on the base of tube says EL39-56.37 and on the box its says 11-56. Is it made in 1956? Grey paint is similar to the Philip Miniwatt EL3N red paint. I imagine the paint will fall off easily and then it will be ugly.

56.37 on tube means 37'week of 1956 for build and 11-56 on the box mean packed in November 56.
Mine have no Box

 

[OctavianH]

I've just received my pair of Fivre 6N7G. Unopened, seem unused. Let's hope these work. Now I have to think how to measure these with DuoVac. I think that I can measure each triode exactly like with 6J5 (A2/G2/K2 and then A1/G1/K1). For the triodes in parallel I think I just have to link A1+A2 and G1+G2. There is a common cathode so it remains single. Brrr, am I right @hpamdr ?

I never understood why these guys are putting those papers on them. But they look quite nice.

 

[hpamdr]

I've just received my pair of Fivre 6N7G. Unopened, seem unused. Let's hope these work. Now I have to think how to measure these with DuoVac. I think that I can measure each triode exactly like with 6J5 (A2/G2/K2 and then A1/G1/K1). For the triodes in parallel I think I just have to link A1+A2 and G1+G2. There is a common cathode so it remains single. Brrr, am I right @hpamdr ?

Yes you are right about the 3 measures T1 ( A1/G1/K), T2 (A2/G2/K), T1+T2 (A1+A2,G1+G2, K)for each tube.
I do not know if DuoVac measure in same time Va and Vs if yes you can measure both triode at once.
Set Va = Vs = 180 or 200V before stating measure.
plug: from tube pin to measure plugs
K -> K
G1 and G2 -> G
A1 -> A
A2 -> S (g2)

I never understood why these guys are putting those papers on them. But they look quite nice.

Italian like a lot those paper in tube... Most of the tube for administration in Italy have such label...

 

[OctavianH]

Yes you are right about the 3 measures T1 ( A1/G1/K), T2 (A2/G2/K), T1+T2 (A1+A2,G1+G2, K)for each tube.
I do not know if DuoVac measure in same time Va and Vs if yes you can measure both triode at once.
Set Va = Vs = 180 or 200V before stating measure.
plug: from tube pin to measure plugs
K -> K
G1 and G2 -> G
A1 -> A
A2 -> S (g2)

Well, I've tried to measure each triode and worked. Just exchanged pin 3->6 for anodes and pin 4->5 for grids.

But then I said, let's measure as if inserted in Eternity in the 6J5 slots, so I just connected A1+A2 and G1+G2 and it worked:

With this type of connection I measured around -3.5V decent current around 4mA:

I think I would put the bias to -3.6V to be sure the second one does not go too high over 5mA. Anyway, putting triodes in parallel somehow compensated the unmatching. Maybe this is why on Elise you do not really care to pair anything and it will somehow work. Yep folks, these are my findings. Many thanks for help.

In the end, a picture with the "decorations". Ministero Delle Finanze!