Have you tried grounding the front panel?
Best Regards
Laurie Biddulph
Mobile: 0400 257 645
Phone: +61 (0)2 4340 0938
Web: www.elby-designs.com
Skype: widgetoz
Elby Designs
9 Follan Close
Kariong
NSW 2250
Australia
Best Regards
Laurie Biddulph
Mobile: 0400 257 645
Phone: +61 (0)2 4340 0938
Web: www.elby-designs.com
Skype: widgetoz
Elby Designs
9 Follan Close
Kariong
NSW 2250
Australia
On 11/02/2015 7:33 AM, ukukey@... [cgs_synth] wrote:
>
>
> I have installed a trimmer and I have found out that with adding a
> 270Kohm resistor to the existing 100Kohm resistor (370Kohm in total) ,
> the gain potentiometer works in full range :) thanks for pointing this
> out Richard :)
> Ken suggested that the previous range was "normal" behavior; I have just
> build it and I have not spent enough time experimenting so I can not
> understand quite well why.
> I am pretty sure Ken knows what he is talking about, since he is the
> "father" of our modules ;)
> I am wondering what provides better functionality, leave it unmodified
> as Ken suggests or add 270Kohm resistor?
>
> About the light hum I am experiencing, i have installed shielded cables
> to the inputs but nothing changed. the hum is audible only when
> increasing the gain control. Could it be that the hum is the regular
> noisefloor resulting by tube's operation? It is my first "tube" project
> , so I dont know what kind of behavior to ex pect.
>
> Gentlemen, thank you all for your time and your help, I deeply
> appreciate it.
>
>