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7z4 tube in place of 7y4 are they compatible
Derek38
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Posts: 28
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City: Salisbury State, Province, Country: NC
#1

12-18-2019, 10:29 PM
In my 41-608 I just noticed that someone substituted a 7z4 tube for a 7y4 will that cause a problem?
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Ron Ramirez
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City: Ferdinand State, Province, Country: Indiana
#2

12-18-2019, 10:52 PM
Yes - the 7Z4 has a higher heater current (0.9A) than the 7Y4 (0.5A). This will stress the power transformer. You don't want to stress a nearly 80 year old power transformer if you can avoid it.
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Ron Ramirez
Ferdinand IN
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