investigating the russian 6S6B-V tube

[Khron]

How much less gain?

http://livinginthepast-audioweb.co.uk/index.php?p=valvegaincalcs
"Even the sparsest information usually lists the µ value, but be aware that the value can change somewhat with other parameters, so it should be accompanied by specific values for Va and Ia. That is, the stated µ is achieved with these other values being true. If the valve is a high gain triode like e.g. ECC83, then the µ doesn't usually change greatly, which makes it easier. If it's a low gain triode like ECC82 etc., then it can vary more so with changes in Va and Ia, so check it with the graph for the particular value of anode current you want to operate."

 

[Papa Tango Charly]

 

[Papa Tango Charly]

we need english translator for this datasheet
Rare Russian 6S6B-I Tube subminiature Triode
Лампа 6С6Б (триод) — DataSheet
https://audioportal.su/diy/spravochnik/radiolampy/lampa-6s6b-triod.html

 

[Papa Tango Charly]

I would like to find

RI is in KOhm
U = (mu) in MOhm
RL is 95,24
How can i do that ?
Thank you







Technical specifications:

• Heating voltage: 6.3V
• Anode voltage: 120V
• Grid bias voltage: -2V
• Heating current: 200 ± 20mA
• Current in the anode circuit: 9 ± 2.5mA
• The steepness of the characteristic: 5mA/V
• Gain 25
• Input impedance at a frequency of 5MHz: about 16KOhm
• Service life: not less than 5000 hours.

 

[Khron]

According to that graph, at about 1mA anode/plate current, which is what we're looking at in microphones, Ri looks to be about 14Kohm.

You won't find "mu in MOhm" because mu has no dimension, it's a ratio (amplification factor; output amplitude divided by input amplitude).
At the above-mentioned 1mA, mu should be about 20-21. Maybe. Not sure the datasheet mentions the exact conditions (surrounding components, supply voltage etc) those figures were measured in.

What is "RL"?

That being said, you can find the gain of your circuit by applying a fixed, known-amplitude voltage to the input of your circuit (tube grid), and measure the amplitude you get at the anode (ideally after the DC-blocking capacitor, to avoid poking into high voltages).

 

[Papa Tango Charly]

According to that graph, at about 1mA anode/plate current, which is what we're looking at in microphones, Ri looks to be about 14Kohm.

You won't find "mu in MOhm" because mu has no dimension, it's a ratio (amplification factor; output amplitude divided by input amplitude).
At the above-mentioned 1mA, mu should be about 20-21. Maybe. Not sure the datasheet mentions the exact conditions (surrounding components, supply voltage etc) those figures were measured in.

What is "RL"?

That being said, you can find the gain of your circuit by applying a fixed, known-amplitude voltage to the input of your circuit (tube grid), and measure the amplitude you get at the anode (ideally after the DC-blocking capacitor, to avoid poking into high voltages).

Thank you very much Khron
I saw this value
https://soviet-tubes.com/product/6s6b-i-tube-triode/

• Current in the anode circuit: 9 ± 2.5mA

Does it has anything relating to mu? if yes what could be mu.
Yours Sincerely

 

[Khron]

Given the size of the tube and the order of magnitude of that figure, sounds more like "maximum anode current" to me, but i could be wrong.

 

[Papa Tango Charly]

Given the size of the tube and the order of magnitude of that figure, sounds more like "maximum anode current" to me, but i could be wrong.

Thank you Khron
I'm very interested with this conversation
If the current in the anode circuit: 2.5mA then what is mu?
Can you tell me where you have found 1mA as mu in the document?

If the greater power distributed 1,2ma then what is mu?








Thank you
Sincerely yours

 

[Papa Tango Charly]

Do you think there could be a gain disparity between the 6S6B-V tubes?

 

[RuudNL]

No. I have tested over 100 6S6B-V tubes and they are very consistent.

 

[mrbutterskin]

Echoing what RuudNL says, I have plenty of 6S6B and never had any that even varied a dB. More likely, you should check the biasing of the tubes in your circuit. The datasheet might say 9mA but that's at ONE specific point in the operation. In microphones, you are generally only running the tube at 500uA-1mA. You need to measure the anode and cathode voltage as well as the voltage drop across the B+ supply resistor to find the operating point. In most uses, the Ri will be around 12-14K and mA/V is around 1.6-1.8

 

[Papa Tango Charly]

Thank you for all your support
Sincerely yours

 

[elskardio]

Hi Guys,
Looking at buying 6S6B tubes and I see 6S6B-I, 6S6B-V or just 6S6B.
Are they all the same?
Cheers

 

[Somkereki]

The "V" mark at the end of the tube type designation means the military version. It has a longer life and better quality.

 

[Somkereki]

No. I have tested over 100 6S6B-V tubes and they are very consistent.

I agree ! Although I tested only 50 such tubes, they are all flawless and very similar. They have a 1977 date stamp.