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38-690 questions
#1

I am restoring a 690. Looking for an original speaker, but wonder if I find a correct sized one, but different field coil resistance. Can I just add the proper resistor in series and have it work OK? The original field coil is 4300 Ohms, shunted across the B+.
Also I notice that someone replaced the rectifier socket atop a transformer with an octal socket and are using a 5U4 instead of a 5X4. To a collector is this a big negative, or should I go back to the original?

Also would like to communicate with anyone who has/is done a restoration. Need all the tips I can get.


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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