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38-116 distortion
#1

Seeking some assistance with the 116....again......

It is currently playing on all 5 bands and has a tremendous sensitivity on all 5! Having come this far, my only remaining frustration is a bit of distortion. I had hoped that having the speaker reconed would solve the problem. It did NOT.

All resistors and caps have been changed along with bad wiring. The chassis was aligned with a signal generator per specs. Now working with the following voltages:

Plate voltage 6L6 is supposed to be 290, I'm running 324, pin 4 (S) is supposed to be 300, I'm running 335. Bias is -22.5. At the 6R7, I'm supposed to have 70v, and I have 85V. All other voltages in the radio seem to be on target.

Surprising today, having failed to put both 6L6 tubes in the chassis, it fired right up on one 6L6 and sounds GREAT....adding the second 6L6 brings the distortion. The result is the same regardless of which 6L6 is removed from the circuit. Sounds great with ONE but not BOTH power tubes. Do I have an issue with my output transformer? The resistance is all "good"....the field coil and output transformer all have the correct voltages.

I'm at a loss....any advice?

Thanks!


Messages In This Thread
38-116 distortion - by bm071 - 01-29-2012, 06:32 PM
Re: 38-116 distortion - by codefox1 - 01-29-2012, 07:16 PM
Re: 38-116 distortion - by bm071 - 01-29-2012, 08:03 PM
Re: 38-116 distortion - by 7estatdef - 01-29-2012, 09:26 PM
Re: 38-116 distortion - by bm071 - 01-29-2012, 10:17 PM
Re: 38-116 distortion - by codefox1 - 01-30-2012, 12:15 PM
Re: 38-116 distortion - by bm071 - 01-30-2012, 01:15 PM
Re: 38-116 distortion - by 7estatdef - 01-30-2012, 03:33 PM
Re: 38-116 distortion - by bm071 - 01-30-2012, 10:33 PM



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