[RTTY] Heathkit SB-1000 On RTTY

[Thomas F Giella NZ4O]

I have a Heathkit SB-1000 amplifier with the single 3-500Z. The manual for the Heathkit SB-1000 says a maximum plate current of 400 mA for CW and 550 mA on SSB. 

What would be a safe maximum plate current for RTTY operation, which is obviously 100% duty cycle like AM operation? 

73 & GUD DX,
Thomas F. Giella NZ4O
Lakeland, FL, USA
nz4o at tampabay.rr.com

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