# HH Scott 222C Amplifier 7189 tube red plating

**URL:** <https://forum.psaudio.com/t/hh-scott-222c-amplifier-7189-tube-red-plating/14786>\
**Category:** Do It Yourself\
**Created:** [January 11, 2020, 8:00pm UTC](https://forum.psaudio.com/t/hh-scott-222c-amplifier-7189-tube-red-plating/14786 "2020-01-11T20:00:31Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![mycrowave](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/mycrowave/32/22659_2.png) [@mycrowave](https://forum.psaudio.com/u/mycrowave)\
**Post date:** [January 11, 2020, 8:00pm UTC](https://forum.psaudio.com/t/hh-scott-222c-amplifier-7189-tube-red-plating/14786/1 "2020-01-11T20:00:31Z")

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I’m considering restoring an old HH Scott 222c amplifier that I have had since I was a teen. It has not been powered on in about 20 years. I powered it on today (nothing blew up thankfully) and noticed that one of the 7189 tubes was red plating. I quickly turned it off.

I then swapped the tube with another 7189 in the amp and the red plate followed the tube. I believe that this would mean that the tube is bad. Does anyone know if I am correct in this diagnosis?

Thanks.