[Amps] Alpha 99 Exhaust vent temps

[Warren Dean]

Hello all. I was referred to this list by Glenn, AE0Q, for an answer to my question about Alpha 99 exhaust temperatures. I am seeing about 155 to 160 degrees F when running RTTY with 4.5 second transmissions at 500 watts. It doesn't really seem all that high to me but I would like to make sure I am not cooking the tubes. Has anyone here looked at exhaust temps and determined what a safe temperature range is? I am using an NIST traceable thermometer about ½ inch above the vents in the case, so the temps are pretty accurate.

Thanks and 73

Warren / NI5L