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6550-B Pinout
basing pinout

 

6550-B Substitutes
Close or identical 6550, 6550A, CK6550
Different rating or performance 6550C, CV5220, KT88, KT88S, KT88SC, KT90, SV6550C

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.

 

6550-B Ratings
Vh
V
Ih
A
VaMax
V
VhkMax
V
PaMax
W
Pg2Max
W
IkMax
mA
Cgk
pF
Cak
pF
Cga
pF
6.3 1.6 660 200 42 6 190 14.0 12.0 0.85

 

6550-B Application Data
Class Va
V
Vg2
V
Vg1
V
Ia
mA
Ig2
mA
Ra
Ω
S
mA/V
Rk
Ω
Zout
Ω
Pout
W
THD
%
Notes
A1 400 225 -16.5 87.0 4.0 3,000 20.0
A1 250 250 -14.0 140 12.0 15,000 11.0 1,500 12.5
AB1 400 310 170 10.0 140 common 5,000 40 0.7
AB1 400 270 -23.0 170 9.0 3,500 60 0.6
AB1 450 310 -29.5 150 9.0 3,500 77 1.5
AB1 600 300 -32.5 100 5.0 5,000 100 3.0
AB1 395 170 12.5 200 common 5,600 34 1.5 UL 40% taps
AB1 450 -48.0 150 12.0 4,000 70 2.4 UL 40% taps

 

6550-B Data sheet links
Dave Cigna''s Pages (DuncanAmps mirror) 6550: html
Peter Millett 6550: Acrobat PDF 100K
The Valve Museum KT88: html
Frank Philipse (Wildcat mirror - Jörg Jan Münter) 6550: 6201.pdf (902849 bytes), 6550.pdf (135652 bytes), 6550.pdf (421187 bytes)  6550A: 6550A.pdf (606171 bytes)  KT88: KT88.pdf (236209 bytes), KT88.pdf (434345 bytes), KT88.pdf (633155 bytes), KT88spec.pdf (70096 bytes), KT88_GEC.pdf (9774126 bytes)  KT90: KT90.pdf (67175 bytes)  SV6550C: 6550C.pdf (51387 bytes)
TubeZone KT90: pdf
Wikipedia 6550: Wikipedia page

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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