6146 mod for FT-101E

[k3jls]

Hi Folks,

Converting an FT-101 to 6146B (or the 12 volt equivalent - the 6883B) can be easily done and will produce slightly over 100 watts on the lower frequencies and up to 80 watts on 10 meters.  Properly neutralized (there were some errors in the 1999 QST article), there are no birdies, snaps, crackles or pops whatsoever.  I have just recently converted 2 FT-101E's and another ham has done one as well.

To facilitate the conversion, we've prepared a website with instructions and pictures - www.k3jls.net/FT-101.html .  While still 'preliminary', we hope to finalize it shortly.

If you do check it out, please e-mail me with any comments, suggestions or constructive criticisms.

If you are able to find a good matched set of 6SJ6C tubes, then the conversion is moot.  Admittedly, these TV sweep tubes will produce more RF than the 6146's, and at a lower plate voltage as well. 

But the 6146B tube family has been designed for RF use, is clearly more rugged, is less expensive, and is more easily secured.  This is probably why Yaesu opted for the 6146's in the redesigned FT-101ZD series.

73's - Joe - K3JLS

[Knightt150]

Hello: I have done the mod it works up to a point, I could not netralize the FT 101E on 10m. I belong to a groupe of FT101E lovers, the FOX TANGO groupe. They say DO NOT DO the modification It will cause squeals and strange noise back in the receiver. I did not experance anything like that.

John W9BFO

[k3jls]

Hello John - Nice to meet you.

I was just wondering, did you do the mod as described on our website www.k3jls.net/FT-101.html  ?

We have converted 3 radios and they all neutralize properly on 10 meters.  (As a matter of fact, I have the required parts to convert 2 more sets).

The 'pops, whistles and crackles' reported by those on the Yahoo Users' group were caused by the way that the author of the 1999 QST article had neutralized the finals, with a 2000 pf capacitor.  I initially tried the 2000 pf cap and my FT-101 couldn't be neutralized on the higher frequencies either. I experienced the same problems!

But, if you follow the instructions on the above website (use a 390 pf mica cap), your finals will work properly.

Please e-mail me directly k3jls@verizon.net if you would like to discuss further.

73's - Joe

[Knightt150]

Joe: I tried to send you a email on the 6146 converson but it did not work. I have a converted FT101E now, but I just cant netrulize it on 10m. You say you have the parts to do one the correct way, let me know how much and when. Maybe all I need is the smaller cap. The conversion I have done works great like I say up to a point.

John W9BFO
email w9bfo-am@charter.net