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Design voltage for 38-116 oscillator grid ?
#4

Thanks Terry for comments. All rdgs with DMM. Have FET and will xcheck.Problem was lo sensitivity on lo end.Osc plate and screen design are 225V and 90 V respectivly. My rdgs were200V on osc plate and 66V on screen.Osc rdgs were -2.0V with tuning cap open and +0.5V fully closed.I think a positive osc grid voltage is a no-no.Installed a NOS 6A8G and osc grid rdgs were -3.5V open and+0.1V closed.Replaced rect with NOS 5X4G andOsc plate and screen were 243V and104V respectively.Osc grid rdgs were-5.4V and-.29V open to closed.Very sensitive using 50 foot flat top in attic but still concerned that lo end may not be as good as "new".Have 17 pages of notes on work-problems; most fun I've had in years.Any thoughts on what is normal osc grid voltage when adjusting tuning cap from open to closed?
Curt


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Re: Design voltage for 38-116 oscillator grid ? - by dixierat - 01-20-2010, 10:44 PM
A little off topic - by 7estatdef - 01-21-2010, 09:36 PM



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