[Heathkit] [Heath] 6146B Issues

[L L bahr]

What specif ic rigs have a problem with these tubes, Glen?  I have used them in Globe Scouts, DX -60s, DX -100s, TX-1s, Viking IIs, Rangers, Valiants, Collins 32S transmitters, and Collins KWM-2 rigs and yet have to have my first problem with a 6146B tube not neutralizing or causing any other problem.  I also have used them in some lesser known transmitters too with no problem.  My friend WA5VGO, who also is also an avid restorer has never had a problem with them either.  Another friend of mine recently put the Bs in his Kenwood TS520S with no problem.  So if indeed there is a problem, it is so small,  it is insignificant.   Surely if there were a problem,  I would have stumb led upon it with all the 6146B tubes I have used over the years.  This paper of yours has brought upon the ham community a concern I find to be out of proportion with reality.  (I know fear was not your  intent,  but the paper has alarmed a lot of people in not wanting to use them in their HF gear. )   I say to the ham community, try them and find out for yourself what is fact or fiction.  If I were you,  I'd be more worried about the sky falling down on me before worrying if 6146B tubes will work in my HF gear.   

Lee, w0vt 


  




I never said that the 6146B/8298A cannot be made to work in all rigs.  What I do say is that those tubes are problematic in many transmitters and, as such, using them is not always "plug and play"! 


I also said that there are those who have had absolutely no problems using the 6146B/8298A in transmitters designed for the 6146 and 6146A/8298.  However, there are plenty of examples where using the later tubes have caused problems.   


I also agree that the "numbers" on the 6146B/8298A are basically the same as the earlier versions.  However, the 6146B/8298A tubes are harder to neutralize in many situations.  Why that?  I have no idea! 


I have, somewhere in my files, a letter from RCA acknowledging the fact that the later tubes are not suitable for use in commercial FM two-way transmitters that were designed for the earlier tubes because of the neutralization. 

  
Glen, K9STH