I have an HB-3 here that shows a data sheet for the 4-400A dated 9-62. I also have an Eimac catalog from the early 1950s that shows the 4-400.
73, Barrie, W7ALW ----- Original Message ----- From: "John Lawson" <[EMAIL PROTECTED]> To: "Discussion of AM Radio in the Amateur Service" <[email protected]> Sent: Friday, March 23, 2007 9:32 AM Subject: Re: [AMRadio] Mfg date for 4-400 series > > > On Fri, 23 Mar 2007, Bob wrote: > > > According to the info that I have, they were in production in 1950. They > > were not listed in the 1948 data sheets. So it could be between 1948 and > > 1950. > > > > Hope this helps. > > Actually, this deepens the Mystery - both my HB3s reach from the late > 30s to the early 60s... they were updated by subscription, so it depended > on who had them as to exactly which updates got posted. > > I have a 1962 TT5 that goes directly from 4-250A to 4-1000, as do the > HB-3 sets. > > I am lacking RCA transmitting tube data from 1963 - 1971. > > The 4-400 does appear in the 1972 TT5 manual. > > So: if they were made starting in 1950 - why are they not in the data > books until nearly 15 years later..? > > I'm sure there's a fine answer out there, somewhere.... just one of > those trivial pusuits to distract one from the day's Business.. ;} > > > Cheers > > John > KB6SCO > DM09fg > > ______________________________________________________________ > AMRadio mailing list > List Rules (must read!): http://w5ami.net/amradiofaq.html > List Home: http://mailman.qth.net/mailman/listinfo/amradio > Partner Website: http://www.amfone.net > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:[email protected] > To unsubscribe, send an email to [EMAIL PROTECTED] with > the word unsubscribe in the message body. > > ______________________________________________________________ AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:[email protected] To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
