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Old 13th May 2013, 06:43 PM   #2231
stajo is offline stajo  Sweden
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This is fun. Basic research for me. So I made a rectify and passive filtering of the 6,3 V I had at hand. Pic 1

Pic 2 is the new curve of the ashy RCA black anodes that made the worst result before with AC. Channel 2 is the rectified filaments. Interesting?
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File Type: jpg new setup 024 (2000x3000).jpg (369.7 KB, 115 views)
File Type: jpg new setup 028 (3000x2000).jpg (852.1 KB, 108 views)

Last edited by stajo; 13th May 2013 at 06:57 PM.
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Old 13th May 2013, 07:16 PM   #2232
Salas is offline Salas  Greece
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Makes sense. Plus educational.
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Old 13th May 2013, 07:18 PM   #2233
stajo is offline stajo  Sweden
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I cant stop blabbering. Look at tube differences. They eat around the same starved voltages with rectified and smoothed 6,3 v (around 5,8 V) wich they absolutely dont when CSS feeded. Then they vary around 1 V. And those are the differences on 3 tubes. 1 Ashy RCA, 2 Clear RCA, 3 Ashy Philips. Note those are DC lifted to 58 V at their usual ground (zero)
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File Type: jpg new setup 029 (3000x2000).jpg (851.2 KB, 94 views)
File Type: jpg new setup 030 (3000x2000).jpg (833.5 KB, 79 views)
File Type: jpg new setup 031 (3000x2000).jpg (838.2 KB, 70 views)

Last edited by stajo; 13th May 2013 at 07:21 PM.
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Old 13th May 2013, 07:23 PM   #2234
6L6 is offline 6L6  United States
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Stajo - Great information! Keep it coming!!

What are you measuring in the above photos? I can't figure it out... What are you looking at on Chanel 1, and what is channel 2?
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Old 13th May 2013, 07:31 PM   #2235
stajo is offline stajo  Sweden
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Quote:
Originally Posted by 6L6 View Post
Stajo - Great information! Keep it coming!!?
Thanks! Im famous for rolling OT but this is not so much about building a great amp for me at the moment. Its more about investigating what affects what and learn to measure it with the tools I have at hand. Glad you enjoy.

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Originally Posted by 6L6 View Post
What are you measuring in the above photos? I can't figure it out... What are you looking at on Chanel 1, and what is channel 2?
Channel 1 is output from one channel on the current build (6V6 AF) after cap measured with 1x probe on max sensitivity on my scope, 2 mV/div. So we are talking high SNR here even so.

Channel 2 is filaments on different 6V6es. All from AC to DC.

So next task is to CSS reg the filaments, but then I need to voltdouble the 6,3 V AC and rig a LM CSS. Gonna take time. Either that or some beers at the pub. What do you think?
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Old 13th May 2013, 07:35 PM   #2236
6L6 is offline 6L6  United States
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Quote:
Originally Posted by stajo View Post
Channel 1 is output from one channel on the current build (6V6 AF) after cap measured with 1x probe on max sensitivity on my scope, 2 mV/div. So we are talking high SNR here even so.

Channel 2 is filaments on different 6V6es. All from AC to DC.
Ok, that is making more sense. Thanks!

So Channel 1 is the noise on the output?

Is the input shorted or open?

And channel 2 is filament noise?
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Old 13th May 2013, 07:36 PM   #2237
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Both! But do the pub after your work. Beer+electronics='Oops', fried components/builder!
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Old 13th May 2013, 07:38 PM   #2238
stajo is offline stajo  Sweden
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G1 has a 68k fixed to ground atm.

Ch 1 is noice at output yes, probably mixed with noicy environment but its the differences that is interesting, not the exact measurements.

Channel 2 is half-poor rectified filaments, made from what I had handy.

1x probe on both and 2 mV/div
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Old 13th May 2013, 07:42 PM   #2239
6L6 is offline 6L6  United States
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Quote:
Originally Posted by stajo View Post
Ch 1 is noice at output yes, probably mixed with noicy environment but its the differences that is interesting, not the exact measurements.
The differences are very interesting - I knew that the changes were due to the different tubes, and that's why I wanted clarification on what you were measuring.

Nice 'scope, by the way...
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Old 13th May 2013, 08:10 PM   #2240
stajo is offline stajo  Sweden
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The million dollar question now must be: Why does the frequency of the disturbance vary between different tubes with the same config, measured on the same 10 minutes? Toob guys! ZM?
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