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Vintage Test Gear and Workshop Equipment For discussions about vintage test gear and workshop equipment such as coil winders. |
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26th Mar 2023, 8:06 pm | #1 |
Heptode
Join Date: Jul 2018
Location: Worthing, West Sussex, UK.
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Taylor 45B mu setting for an EL33?
The data sheet for the valve is s= 9mA/V, I assume that "s" is the same as mu?
Anyway, the 45B has two mu settings which give vastly differing results with this particular valve. Do I use 3mA/V or 15 mA/V setting to get the correct reading? I am guessing the latter.
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27th Mar 2023, 1:40 pm | #2 | |
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Re: Taylor 45B mu setting for an EL33?
Quote:
http://www.r-type.org/exhib/aad0112.htm This matches the info given in the AVO Valve Data Manual. I'm not familiar with the Taylor 45B, but I would expect mA/V to be something you measure rather than set?
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27th Mar 2023, 2:25 pm | #3 |
Dekatron
Join Date: Apr 2011
Location: Cornwall, UK.
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Re: Taylor 45B mu setting for an EL33?
According to the valve chart I'm looking at the expected mutual conductance for a full emission valve is 5.5ma/V @ Va = Vg2 = 100 Volts & Vg1 = 2 Volts -ve, so set to read the 15maV scale if that's the case:
http://bee.mif.pg.gda.pl/ciasteczkow...5b_46a_47a.pdf Lawrence. Last edited by ms660; 27th Mar 2023 at 2:31 pm. Reason: link added and addition |
27th Mar 2023, 3:36 pm | #4 | |
Rest in Peace
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Re: Taylor 45B mu setting for an EL33?
To avoid possible confusion it's worth clarifying that mu (μ) is the amplification factor of a valve, whereas the tester measures mutual conductance (gm) which is a different parameter.
μ = gm x ra, i.e. amplification factor is the product of mutual conductance and anode resistance. Quote:
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27th Mar 2023, 3:58 pm | #5 |
Dekatron
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Location: Cornwall, UK.
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Re: Taylor 45B mu setting for an EL33?
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27th Mar 2023, 4:26 pm | #6 | ||
Heptode
Join Date: Jul 2018
Location: Worthing, West Sussex, UK.
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Re: Taylor 45B mu setting for an EL33?
Quote:
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27th Mar 2023, 5:43 pm | #7 |
Heptode
Join Date: Jul 2018
Location: Worthing, West Sussex, UK.
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Re: Taylor 45B mu setting for an EL33?
I just re-measured the EL33 on the 15mA/V setting.
According to the valve chart booklet that comes with the Taylor Windsor 45B the mutual conductance reading should be 5.5, the measurement I get is just under at 5.2 ish, The thing that confused me is that 5.5 is in the "REPLACE" region of the meter scale After reading the instruction manual (you know the book you read after trying everything else) it Implies that the GOOD or REPLACE area of the meter only refers to Rectifiers. See uploaded image. https://prnt.sc/D9V5xpPi73_1
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27th Mar 2023, 8:56 pm | #8 |
Heptode
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Re: Taylor 45B mu setting for an EL33?
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