AMP MAKER N5X - Page 39

Checking dissipation - Octal valves[
This section covers an amplier with a 6V6/6L6/EL34 power valve. Use the section above if you are
using an EL84.
1 - Octal cathode current: Divide the cathode voltage (H-J) by the value of R17 (470 Ohms). A typical
result is around 30-40mA, depending on the valve you are using. Contact Amp Maker if it's more than
50mA.
_________mA
2 - Octal screen current: Divide the K-L gure by the value of R18 (2.2k Ohms). A typical result is 2-
4mA. Get in touch if it's more than 6mA.
_________mA
3 - Octal plate current: Subtract the screen current (2, above) from the cathode current (1, above) to
get the valve's plate current. A typical result is 36-40mA. Contact Amp Maker if your result is more than
45mA.
_________mA
4 - Octal plate dissipation: Multiply the J-M gure by the octal plate current you've just calculated (3,
above). For example, 235V * 0.037A = 8.7 Watts dissipated by the octal valve's plate.
_________W
For 6V6 valves, any value under 12W is ne. For 6L6/EL34 a value up to 15W is ne.
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