unwanted buzz/humm

[RobSm01]

Hi.
I have a hum that is leaving me non-plussed.

I have measured the resistance of all possible pairings - jack, tone, volume, switch, pickup 1, pickup 2 (covers) and always get a zero reading. I have used a common ground for all components ie each ground wire is individually soldered to the 'common ground'.

The hum is probably 'liveable with' ie not intrusive compared to the volume of the guitar, but it is alleviated by touching any of the above mentioned components , so i'm a little perturbed.

Touching the bridge or touching the strings has no effect at all.

Also it seems to dissipate almost disappearing over time when I'm playing the guitar.

If you have some ideas I can test in order to identify the source, please let me know.

Thanks,
Rob.

Top

[curtisa]

Is there a good ground connection from strings (bridge ground) to the rest of the grounded components? That could account for the hum getting better when touching any metal component except the strings.

[Bizman62]

Triple check that you've got your jack wired correctly. I had a similar issue and finally found out that despite having very carefully soldered the ground to the sleeve and the hot to the tip they were swapped.

[mistermikev]

couple other random ideas... just rule out issue with cable by trying a dif cable, or try another guitar just to rule in that it is def not an environment issue.  I would check your input jack very carefully... ensure that the live prong isn't making minor contact with the body wood/shielding.  

[RobSm01]

Thanks for the info.
It looks like the earth wire from the bridge to the ground point isn't continuous. I touch a wire from the bridge to the pickup switch and the noise abates. 
I am still nonplussed    as to how this might've happened , bur more so with the prospect of withdrawing a bridge-post and replacing the wire....

[Bizman62]

On 4/8/2023 at 6:07 AM, RobSm01 said:

I am still nonplussed    as to how this might've happened

Could be poor quality wire made out of poorly mixed Chinese pot metal instead of properly conductive metal. Or some other manufacturing defect, the quality control most likely doesn't check end to end conductivity on a mile long roll. Or the wire may just have snapped when you pushed the bridge-post in - again that's something that quality wire shouldn't do. Or slid back into the the wire channel instead of being grabbed between the post and the hole. Plenty of options for Mr. Murphy!