Western electric kt 88 brochure
This is the 7 pages manual for western electric kt 88 brochure.
Read or download the pdf for free. If you want to contribute, please upload pdfs to audioservicemanuals.wetransfer.com.
Extracted text from western electric kt 88 brochure (Ocr-read)
Page 1
Page 2 of 7 MAXIMUM RATINGS Absolute Design Maximum Units V a 800 800 V V g2 600 600 V V a, g 2 600 600 V V g 1 200 200 V P a 42 35 W P g2 8 6 W P a+g2 46 40 W I k 230 230 ma V h-k 250 200 V T bulb 250 250 degrees C R g1-k (cathode bias) P a|g2 < 135W 470 k ohm P a|g2 > 35W 270 k ohm R g1-k (fixed bias) P a|g2 < 135W 220 k ohm P a|g2 > 35W 100 k ohm CAPACITANCES (Measured on a cold unscreened valve) Triode Connection C g1-a.g.2 : 7.9pF C g1-all less a.g2 : 9.3pF C a.g2 -all less g1 : 17pF Tetrode Connection C g1-a : 1.2pF C al -all less a : 16pF C a -all less g1 : 12pF CHARACTERISTICS Tetrode Connected V a 250 V V g2 250 V I a 140 mA I g2 3 (approx) mA V g1 15 (approx) V g m 11.5 mA/V r a 12 ohms µ g1-g2 8 -- Triode Connected Va,g2 250 V I a+ g2 143 mA -V g1 15 approx V g m 12 mA/V r a 670 ohms µ 8 --
Page 2
Page 3 of 7 TYPICAL OPERATION Push-Pull. Class AB1. Cathode Bias. Tetrode Connection V a(b) 560 V Va(o) 521 V V g2 300 V I a(o) 2 x 64 mA I a(max. sig) 2 x 73 mA I g2(o) 2 x 1.7 mA I g2(max. sig) 2 x 9 mA R L(a-a) 9 kohm R k* 2 x 460 ohm -V g1 30 (approx) V P out 50 W D tot 3 % I.M. 11 % P a(o) 2 x 33 W P a(max. sig) 2 x 12 W P g2(o) 2 x 0.5 W P g2(max. sig) 2 x 2.7 W V in(g1-g1)(pk) 60 V *It is essential to use two separate cathode bias resistors. **Intermodulation distortion: measured using two input signals at 50 and 6000 hz (ratio of amplitudes 4:1) Push-Pull. Class AB1. Fixed Bias. Tetrode Connection Va(b) 560 V V a(o) 552 V V g2 300 V I a(o) 2 x 60 mA I a(max. sig) 2 x 145 mA I g2(o) 2 x 1.7 mA I g2(max. sig) 2 x 15 mA R L(a-a) 4.5 kohm -V g1 34 (approx) V P out 100 W D tot 2.5 % I.M. 10 % P a(o) 2 x 33 W P a(max. sig) 2 x 28 W P g2(o) 2 x 0.5 W P g2(max. sig) 2 x 4.5 W V in(g1-g1)(pk) 67 V *It is essential to provide two separately adjustable bias voltage sources, having a voltage adjustment range of 25%. **Intermodulation distortion: measured using two input signals at 50 and 6000 hz (ratio of amplitudes 4:1).