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THE AM BULLETIN BOARD => Technical Forum => Topic started by: N4RMT on April 04, 2016, 05:11:34 PM



Title: Ranger 2: Overheat that bad, or bad tube?
Post by: N4RMT on April 04, 2016, 05:11:34 PM
Hey guys.

Installed a JAN 6197 in the buffer / multiplier socket on my ranger 2 a week or so back.  Used it extensively on a couple of separate occasions.  Today, I turned on the rig to stand by and went back over to the bench to finish up a project.   It sat idle for maybe an hour or so.   While i was working I heard a QSO start up and thought I'd take a break and join in.  When I went to tune up, there was no drive.  Anyway, long story short, after unplugging the rig and letting it cool, i removed the cabinet and immediately noticed the top of that tube was white.  When I went to pull it, the envelope came out, and left the base and all the innards standing tall!  After cleaning that up, I installed another and off we went, business as usual.   This time with the cabinet off.   You think it over heated that much, or is it more likely the tube was bad to begin with, and I just got lucky the first couple of times?
(http://i272.photobucket.com/albums/jj165/pearlbeater/4639EC19-598D-4780-A061-6FDD032524B8.jpg)


Title: Re: Ranger 2: Overheat that bad, or bad tube?
Post by: w4bfs on April 04, 2016, 05:24:15 PM
I see the green Sylvania paint is still bright on the envelope .... usually an long-term overheated tube will dull the paint toward brown or sluff it off.... I suppose that this was a crack in the glass of the base maybe caused by improper handling .... many people think (erroniously) that rolling the tube around in the socket is a way to clean the pins ....au contrair, mon frere ... straight in and out is proper .... clean dirty/corroded  pins before insertion


Title: Re: Ranger 2: Overheat that bad, or bad tube?
Post by: N4RMT on April 04, 2016, 05:29:15 PM
You know what, beans? I think this it the tube that had a badly bent pin on it.  I don't remember, but i know one of the novals did when i was toobing it up after fixing it.  I bet that's the one, and I made it worse by straightening it.   You jogged my memory!
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