38-690 questions

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38-690 questions

Steve D
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Posts: 115
Threads: 25
Joined: Jul 2006
City: Lebanon, NJ 08833

01-19-2009, 06:25 PM

If you wire the socket to accept dual pin basings, one thing to be careful with is the pin spacing. For the 5Y3/5Y4 for example, if you connect pins 3-4, 5-6, and 2-7 to make it work for both basings then there is only one pin gap between the plate voltage and the filament voltage. Normally there is two pin spacings (blank pin between them) which provides twice the tracking distance.

In older sockets this can lead to carbonization and breakdown. If you decide to do this I would recommend replacing the socket with a modern insulation type which can better withstand the voltage gradients.

Steve D

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Messages In This Thread

38-690 questions - by Guest - 01-19-2009, 12:22 PM

Re: 38-690 questions - by codefox1 - 01-19-2009, 03:42 PM

Re: 38-690 questions - by Doug Houston - 01-19-2009, 04:41 PM

Re: 38-690 questions - by Steve D - 01-19-2009, 06:25 PM

Re: 38-690 questions - by Arran - 01-19-2009, 11:15 PM

Re: 38-690 questions - by Fred R - 01-20-2009, 10:53 AM

Re: 38-690 questions - by FStephenMasek - 01-27-2009, 01:49 AM

Re: 38-690 questions - by Doug Houston - 01-27-2009, 11:06 PM

Re: 38-690 questions - by Arran - 01-28-2009, 04:02 AM

Re: 38-690 questions - by 49Stude63 - 02-01-2009, 01:01 PM

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