Tube Identification

[fauxpas]

This ebay listing of a Yaqin MC5881A amp has the 5881 (6L6) power tubes and 12AX7 / 12AU7 preamp tubes and the other tubes look to me like rectifying tubes, but are listed as 6N6? I looked up 6N6 tubes and they look nothing like those. Can someone tell me what they are?

 

[Burnedfingers]

This ebay listing of a Yaqin MC5881A amp has the 5881 (6L6) power tubes and 12AX7 / 12AU7 preamp tubes and the other tubes look to me like rectifying tubes, but are listed as 6N6? I looked up 6N6 tubes and they look nothing like those. Can someone tell me what they are?

Looks to me like 5881/6l6's, 12AX7, 12AU7, and the other two are display tubes? (showing output?)

 

[Colt45]

I see

4x 6l6
4x 6N1P
2x EMxx (display..)

 

[fauxpas]

OK, 2 of 2 saying display tubes. I'm new to this concept. Are they there just to look pretty? Indicate volume or something?

 

[Ty_Bower]

Have you ever seen the "Magic Eye" indicator? I saw a couple used to indicate signal strength for FM tuners, or record level on reel to reel tape decks.

There is a strip of phosphor or something inside the tube. It gives off an eerie greenish glow. The length of the glowing part of the strip can vary depending on some value - perhaps bias, or input level, or something.

Have a look at the first photo on this page:
http://hhscott.com/cc/magic_eyes.htm

 

[Burnedfingers]

Indicate volume or something?

Yes

 

[fauxpas]

Sweet. Cheers and thanks.

 

[jlsem]

The eye tubes may also be used to indicate balance in the push-pull output stage.

John