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38-116 input transformer
#8

The original input transformer was a step DOWN transformer while this replacement is a step UP transformer.  A local radio guy here says that using a step UP transformer will increase the gain on the output tubes and tend to introduce distortion.  He would NOT remove the negative feedback circuit because that tends to reduce the gain which is needed even more since the replaced transformer is a step up transformer.

That seems to be opposite to what Mondial said yesterday on this thread.   I am NOT a real good electronic theory person so I don't want to proceed until I have a good feel for what I should do.

Also, the local radio guy here (with about 40 years experience but not on this exact set) suggests maybe putting shunt resistors across the secondary windings to bring the measured resistance down from 1.8K ohms to something like 200 -400 ohms. Would the transformer (with a primary of about 715 ohms) then function as a step down transformer OR would I just be screwing things up even more?

Thanks,
Mark


Messages In This Thread
38-116 input transformer - by retiredinprescott - 11-11-2014, 06:41 PM
RE: 38-116 input transformer - by Mondial - 11-11-2014, 07:06 PM
RE: 38-116 input transformer - by Mondial - 11-11-2014, 08:03 PM
RE: 38-116 input transformer - by morzh - 11-12-2014, 03:56 PM
RE: 38-116 input transformer - by retiredinprescott - 11-12-2014, 04:18 PM
RE: 38-116 input transformer - by Mondial - 11-12-2014, 04:27 PM
RE: 38-116 input transformer - by Mondial - 11-12-2014, 04:50 PM
RE: 38-116 input transformer - by Mondial - 11-12-2014, 05:21 PM



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