[R-390] TR: R-390 Woes

[Jacques Fortin]

Hi Jim,
Yes, this should have been the Bill Orr PD mod.
As we are there, VE3TOU (Treetops Circuits) made a plug-in PD for it (well, kind of) see attached.
About trying different tube types on a R-388 PD, I never do it, despite I have one Collins R-388 but it is still to be restored.

73, Jacques, VE2JFE in Montreal

Jacques
Good catch.
I have a 51J-3 aka R-388 that also had the 6BE6 Product Detector mod installed.  It must have been inspired by the Bill Orr Ham Radio magazine article.  I agree that it doesn't work very well.  I removed the mod but haven't decided on what to do.   Either make it work better in SSB or return it to original condition.  I think that there are several pentagrid tubes that have the same pinout as the 6BE6 but are less noisy with higher gain.  Has anyone tried the 6BY6, 6CS6, 5915 or 7036 in place of the 6BE6?
Jim
Logic: Method used to arrive at the wrong conclusion, with confidence.  Murphy 

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