Is this pinout correct on this 5840 tube?

[pucho812]

I took a clip from a schematic of a piece I am working on.  I want to confirm that I have the correct pins labeled for this 5840 tube. I have been over the data sheets and I just want to confirm I have this correct based on what the data sheet says and what I have labeled as the schematic.

According to the data sheet
pin 1 is grid one,
pins 2,4,8 is cathode and gride #3?
pins 3 & 6 are heaters
Pin 5 is there plate
and Pin 7 is grid Screen 2

 

[scott2000]

According to the data sheet
pin 1 is grid one,
pins 2,4,8 is cathode and gride #3?
pins 3 & 6 are heaters
Pin 5 is there plate
and Pin 7 is grid Screen 2

Sounds right to me. Not sure what you're doing with the schematic though.. but I'm guessing you're just asking about the pinout.

 

[pucho812]

I'm helping a friend sort out some issues.
He provided the schematic  I attached and  I added the PIN numbers  in red.  I am just double checking that I labeled things correctly as I am not sure what to do with PIN 8 if anything based on the schematic snippet?

 

[scott2000]

Yeah... Weird looking. I've personally never seen one. But, as you said, 8 is 2 is 4 in this case so, it's already doing something.  Maybe some kind of pentode running as triode deal in this circuit....

 

[pucho812]

dave royer  likes them in his mics.

So would we not connect 8 and 4 then?

 

[scott2000]

Not sure what you are asking.2, 8 and 4 are connected internally. 

I don't know what you're circuit is and ,even then, not sure I could help...lol

Have to admit though, I was confused because of G2 and G3 tied together but that doesn't mean anything..... it's obviously done sometimes

 

[Walrus]

But that circuit shows grid 2 and 3 strapped to anode (plate), and as grid 3 is internally strapped to cathode, you basically have a short circuit valve (tube)! 

 

[pucho812]

But that circuit shows grid 2 and 3 strapped to anode (plate), and as grid 3 is internally strapped to cathode, you basically have a short circuit valve (tube)! 

Would it be best to not connect those then?


Here is a link to the full schematic my buddy is working on. As I am not 100% familiar  with 5840 tubes best to ask the brain trust...


http://www.tab-funkenwerk.org/ami-parts/mic-kits/m49a-kits/m49-schematic/

 

[gridcurrent]

Would it be best to not connect those then?


Here is a link to the full schematic my buddy is working on. As I am not 100% familiar  with 5840 tubes best to ask the brain trust...


http://www.tab-funkenwerk.org/ami-parts/mic-kits/m49a-kits/m49-schematic/

the CK6205 is the "correct" tube for that circuit.

 

[radardoug]

Why dont you just do a web search for the 5840? Took me ten seconds.
http://www.r-type.org/exhib/aab0175.htm

 

[radardoug]

Ah, so you stole the circuit from Oliver, who put a cunning error in the circuit, ensuring it will never work! Hehe!

 

[pucho812]

Ah, so you stole the circuit from Oliver, who put a cunning error in the circuit, ensuring it will never work! Hehe!

nothing stolen here, he is working on a mic kit and asked me some questions.  My buddy also picked up parts from them and they sold him the 5840 tube so I am not sure if that is a mistake or not.

 

[radardoug]

Connecting cathode to plate is definitely a mistake.

 

[Bill Wilson]

You need to connect 4,5,7 together. this makes the tube operate as a triode. Pin 1 is grid input. Wire heater to 6.3vdc & either 2 or 8 are cathode connection points.

 

[pucho812]

You need to connect 4,5,7 together. this makes the tube operate as a triode. Pin 1 is grid input. Wire heater to 6.3vdc & either 2 or 8 are cathode connection points.

Yes but internally pins 4  & 8 are cathode and gride 3 due to internal connections. I asked the source to see what they say, that seems to be the only hold up on this...

 

[pucho812]

straight from tech support, omit  any connections to pins 4 and 8. they do not get used.