| Henry amplifiers use resonated chokes to achieve their normal high 
attenuation of HV power supply hum rejection.   If the resonating capacitor 
has broken down, or if there has been a short across the turns of the 
inductor, the hum level would increase with a few attendant symptoms.  The 
symptoms might include an increase in the unloaded plate voltage and reduced 
stability of the HV.
----- Original Message ----- 
From: "hamguy2" <hamguy2@fuse.net>
To: <amps@contesting.com>
Sent: Sunday, August 06, 2006 11:56 AM
Subject: [Amps] Henry 2KD-5 120 Hz Hum
>I have a Henry 2KD-5 that I am using on AM running 300 watts.
> There is a low level but noticeable 120 Hz hum on the unmodulated
> carrier in CW mode.  The hum is super imposed on the AM signal
> amplitude.  Local stations can hear the hum.  I have tried two
> exciters and they are not the source.  I have recapped the filter
> capacitors to 250 mF without change in symptoms.
>
> Is there something else to check or do I just live with the hum?
>
> ----------------------
> Ron Schuster N9RC
> ---------------------- 
>
> _______________________________________________
> Amps mailing list
> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps 
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
 |