Aren't those the same curves I posted two weeks ago?Triode curves of 6ж52п
Agreed.
View attachment 379190
Looks like you could do a B+ of 300V (plate max is 350V, G2 is 250V) and sit pretty nicely at -1.5 to -1.7Vg @ 20mA (somewhere around 175V), giving you 120V or more in either direction with a CCS.
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Aren't those the same curves I posted two weeks ago?
Ekhm, yes they are. After I had posted them, I realized that.
BTW, I am considering 6ф12п for line preamp and driver combo.
I'm not so sure that the published curves aren't optimistic averages of lots of devices, mine in measurements in pentode connection are quite variable in performance, and my limited measurements at a glance in triode connection don't seem that consistent with the published curves either. I am probably abandoning my planned use of pentode connected 6ж52п in a phono stage design because of a variety of problems with the samples I have. (100% variation in transconductance at a given operating point in pentode connection.)
I'd recommend characterizing a number of samples on the bench in triode connection to make sure you can get the performance you expect.
I'd recommend characterizing a number of samples on the bench in triode connection to make sure you can get the performance you expect.
I have just 4, two match reasonably closely and the other two don't in pentode mode with a single fixed value on the screen while sweeping plate and grid voltages. Not enough to draw a valid conclusion, but enough for me to feel concerned. I have not had any luck modeling this one pentode connected in spice using my uTracer either, whereas I have with other types.
An externally hosted image should be here but it was not working when we last tested it.
The tube I have - notice the filament is not covered. Source: http://www.diyaudio.com/forums/tubes-valves/148610-d3a-pentode-driver-history-tube.html#post1897021
..and those do have filaments covered
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I have no idea yet who made these, right below 6ж52п is a pentagon followed by the date code.
Just shorted the grid connection to chassis and fried something so the utracer is dead for the moment. Grid stuck at -55V so the inverter is alive at least.
Trouble shooting starts after I order the active devices from Digikey. I have to insulate the metal top plate.. (Or come up with some way to limit the current under fault conditions.
Just shorted the grid connection to chassis and fried something so the utracer is dead for the moment. Grid stuck at -55V so the inverter is alive at least.
Trouble shooting starts after I order the active devices from Digikey. I have to insulate the metal top plate.. (Or come up with some way to limit the current under fault conditions.
I popped a couple of transistors in the grid supply of my uTracer and have ordered a variety of different types to try as replacements. I am also going to add a series resistor to limit the output current in the hopes of protecting the supply the next time I short it..
Once I have fixed it I will trace my four 6ж52п and if interesting post the results here. I also have four on the way that were made by Souz in the 1980s..
Once I have fixed it I will trace my four 6ж52п and if interesting post the results here. I also have four on the way that were made by Souz in the 1980s..
Unfortunately I blew up my uTracer last night by shorting out the grid bias supply, just waiting for replacement parts to arrive from Mouser. I will trace the 6ж52п once I have repaired the unit and post the curves here.
One of the four tubes currently in my possession has a racked internal structure so the alignment of electrodes is suspect, the rest seem OK mechanically speaking.
One of the four tubes currently in my possession has a racked internal structure so the alignment of electrodes is suspect, the rest seem OK mechanically speaking.
Hi there,
I did these traces some time ago and didn't have 6z52p at hand unfortunately. I had 6z51p amongst other pentodes that I traced in triode mode....
http://www.bartola.co.uk/valves/2013/02/23/russian-pentodes-in-triode-mode/
Ale
I did these traces some time ago and didn't have 6z52p at hand unfortunately. I had 6z51p amongst other pentodes that I traced in triode mode....
http://www.bartola.co.uk/valves/2013/02/23/russian-pentodes-in-triode-mode/
Ale
Hi there,
I did these traces some time ago and didn't have 6z52p at hand unfortunately. I had 6z51p amongst other pentodes that I traced in triode mode....
http://www.bartola.co.uk/valves/2013/02/23/russian-pentodes-in-triode-mode/
Ale
I have seen them on your website. I can send you one or two to measure if you like.
6ж52п - Ia(Ug) @ Ua=Ug2=170V & 143V
6ж52п triode strapped - measured
Attachments
6ж52п - Ia(Ua) @ Ug2=(-4.0;0.0)
More curves from my manual Lamp tester P-508.
Solid black is polynomial approximation
Data below (1st col. is Ua value)
Ua\Ug -4,0 -3,5 -3,0 -2,5 -2,0 -1,5 -1,0 -0,5 0,0
329 0,60 1,55 4,00 9,40 19,50 36,00 64,00
298 0,33 0,82 2,25 5,60 14,00 26,00 54,00
264 0,18 0,42 1,15 3,28 9,38 21,40 36,00 52,50
235 0,10 0,20 0,60 1,75 5,40 14,50 28,00 44,00 62,00
206 0,05 0,10 0,27 0,82 2,82 9,40 22,30 36,00 54,00
176 0,03 0,05 0,14 0,35 1,33 5,20 15,50 29,00 44,00
146 0,00 0,02 0,07 0,15 0,53 2,50 9,80 22,00 36,00
116 0,00 0,02 0,04 0,07 0,20 0,95 5,00 14,50 28,00
105 0,00 0,00 0,02 0,05 0,14 0,60 3,68 11,50 25,00
More curves from my manual Lamp tester P-508.
Solid black is polynomial approximation
Data below (1st col. is Ua value)
Ua\Ug -4,0 -3,5 -3,0 -2,5 -2,0 -1,5 -1,0 -0,5 0,0
329 0,60 1,55 4,00 9,40 19,50 36,00 64,00
298 0,33 0,82 2,25 5,60 14,00 26,00 54,00
264 0,18 0,42 1,15 3,28 9,38 21,40 36,00 52,50
235 0,10 0,20 0,60 1,75 5,40 14,50 28,00 44,00 62,00
206 0,05 0,10 0,27 0,82 2,82 9,40 22,30 36,00 54,00
176 0,03 0,05 0,14 0,35 1,33 5,20 15,50 29,00 44,00
146 0,00 0,02 0,07 0,15 0,53 2,50 9,80 22,00 36,00
116 0,00 0,02 0,04 0,07 0,20 0,95 5,00 14,50 28,00
105 0,00 0,00 0,02 0,05 0,14 0,60 3,68 11,50 25,00
Attachments
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