I've updated this document in two areas: 1. Added information about the usage of 2-12BA6's and no ballast tube will save 3.5 watts of heat, as the result of a comment I received. 2. Clarified what happens when a diode alone is used instead of the ballast or resistor or other solution.
Same link to it: R390A Ballast RT510-3TF7 tube.pdf (r-390a.net) <https://www.r-390a.net/R390A%20Ballast%20RT510-3TF7%20tube.pdf> Regards, Larry --------------------------------------------------------------------------------------------------------------------------------------------------------------------- On Tue, Jul 25, 2023 at 11:30 PM Larry H <larry4...@gmail.com> wrote: > The R390A Ballast tube (RT510/3TF7) in the IF deck has been a very popular > discussion item on the list forum, off and on for ever. And rightly so, it > is expensive, not very reliable and somewhat fragile. This discussion is so > popular that it has its own section in the 'Pearls' labeled ‘Ballast tube’, > and what a section it is - 239 pages. > > The reason I wrote this document is that the discussions on the list forum > are quite repetitive and the important information can be condensed into a > few pages. Since it would take a person a very long time to go through all > the entries in the Pearls and come to a conclusion, hopefully, this will > save someone a lot of time. My two page summary is at the end of the > document. > > Here's a link to it: R390A Ballast RT510-3TF7 tube.pdf (r-390a.net) > <https://www.r-390a.net/R390A%20Ballast%20RT510-3TF7%20tube.pdf> > > Regards, Larry > ______________________________________________________________ R-390 mailing list Home: http://mailman.qth.net/mailman/listinfo/r-390 Help: http://mailman.qth.net/mmfaq.htm Post: mailto:R-390@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
