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7581-A Pinout
basing pinout

 
7581-A Substitutes
Close or identical 7581

Warning: Substitutes are given as a guide only - please refer to original manufacturers data sheets to ensure that a substitute is safe and appropriate for your application.

 
7581-A Ratings
Vh
V		 Ih
A		 VaMax
V		 Vg2Max
V		 PaMax
W		 Pg2Max
W		 Notes
6.3 0.9 500 450 35.0 5.0 Pentode or UL
6.3 0.9 450 450 35.0 Triode connected

 
7581-A Application Data
Class Va
V		 Vg2
V		 Vg1
V		 Ia
mA		 Ig2
mA		 Ra
Ω		 S
mA/V		 Zout
Ω		 Pout
W
A S/E 350 250 -18.0 54 2.5 33,000 5.2 4,200 10.8
A S/E 300 200 -12.5 48 2.5 35,000 5.3 4,500 6.5
A S/E 250 250 -14.0 72 5.0 22,500 6.0 2,500 6.5
A P/P 270 270 -17.5 134 11.0 5,000 17.5
A P/P 250 250 -16.0 120 10.0 5,000 14.5
AB1 450 400 -37.0 116 5.6 5,600 55.0
AB1 360 270 -22.5 88 5.0 3,800 18.0
AB1 360 270 -22.5 88 5.0 6,600 26.5
AB2 360 270 -22.5 88 5.0 3,800 47.0
AB2 360 225 -18.0 78 3.5 6,000 31.0
A S/E Triode 250 -20.0 40 1,700 4.7 5,000 1.4

 
7581-A Data sheet links
Frank Philipse (Wildcat mirror - Jörg Jan Münter) 7581: 7581.pdf (671272 bytes)  7581A: 7551.pdf (880358 bytes), 7581A.pdf (144900 bytes), 7581A.pdf (863557 bytes)

Bold designators are close or identical, Italic designators are different ratings, different pinouts or different filament voltages. Please see the substitutes at the top of the page for more details

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