Does anyone have 6BQ6 (sweep tube) triode plate curves to share?

[DualTriode]

Hello to the Brain Trust,
I looked about the shop and saw many posts about TV sweep tubes. Today I bought several 6BQ6GTB’s to play with. I want to construct a SET headphone amplifier. I have a pair of 5K : 300 ohm 3 watt Edcor output transformers that work nice with 1625’s and EL34’s. (The setup.)
Here is the request! Does anyone have 6BQ6 triode plate curves to share?
Thank You
DT

[Enzo]

Maybe this helps?

http://frank.pocnet.net/sheets/093/6/6BQ6GA.pdf

http://frank.pocnet.net/sheets/127/6/6BQ6GTB.pdf

[Geek]

How much power do your headphones need?

Cheers!

[DualTriode]

Thank You Enzo and Geek,
The data sheets do help, the triode amplification factor is given. I do not know how to derive triode plate curves, rp, output impedance, and cathode reistor values from the pentode data. I am not oposed to trial and error. I will go eazy to avoid letting the smoke out.
The headphones are Sennheiser HD-600's. My guess is that 0.03 watts will blow the ears off. In terms of watts not much load on a tube that will idle arount 6 + watts. I want to test the idea that a relitivily light load will not drag down the bottom end of the load line. Not the typical way to load a Single End Triode?
Thanks
DT

[ja2dhc]

Originally Posted by DualTriode

Does anyone have 6BQ6 triode plate curves to share?
DT

The attached photo is what you want. The graph was figured by TINA
simulator based on Ayumi's Tube Model of 6BQ6(T). He generated
the 6BQ6(T) model from GE's datasheet.

[DualTriode]

jacdhc,
Yes that is what I wanted. Picking a operating point will have a head start.
Thank You
DT

[DualTriode]

Hello,
This 6BQ6 is a interesting tube. Several fellow DIYers have praised its audio capabilities and noted that it can operate above it name plate horse power. Thank You to jacdhc for the plate curves. I knocked about more on google and also found this link to more data.
homepage2.nifty.com/the-tube/drawin/No148-6BQ6GTB.doc
I also found a reference that called the 6BQ6 a Remote Cutoff tube, also called a variable mu tube. The typical remote cutoff has it grid wound with varying pitch (uneven spacing between the grid wires). An example is the 6ES8. The plate curves really do stack up or have an extended knee. It looks like this tube, 6BQ6 needs to run with plate currents above the knee of the plate curves to avoid exaggerated nonlinear distortion. This might be why the reports that say this tube sounds good also have the tube operating above the manufacturer recommended 11 watts at idle.
Does anyone have thoughts to add?
DT

[ja2dhc]

Originally Posted by DualTriode

homepage2.nifty.com/the-tube/drawin/No148-6BQ6GTB.doc

I also found a reference that called the 6BQ6 a Remote Cutoff tube, also called a variable mu tube.

Hello, The URL is in Mr.Mito's Web page. He is very expert in tubes and
tube circuitry.

I could not find "Remote Cutoff" in the datasheets in the Frank's Web.

[DualTriode]

Hello,
Mr. Mito’s web page has lots of data and technical information, it appears to be the product of much thoughtful work. Unfortunately I can read very little.
The other reference that I found that calls the 6BQ6 a remote Cutoff is the electronic Tube Manual I purchased from TubeCad.com.
I will open a 6BQ6GTB tube carefully with a hammer, take some photos and report back regarding the variable pitch, or not, grid winding.
DT

[ja2dhc]

Originally Posted by DualTriode

Unfortunately I can read very little.

If you need some points from his Web, I can translate it into English.
Please limit the volume less than 10 lines or so.