Univibe: strange reaction to AC cord position

[richon]

Hi,   


my univibe is sounding awesome, but has a strange reaction to the position of the AC cord (que one with 18V AC) 


look at the pictures showing how I have to put the AC cord to avoid the buzzing noise 





heres a video that shows how it sounds:  http://www.youtube.com/watch?v=GjdHdkpyDqo


strange is , also, that the buzzing noise, is pulsating like the LFO...  right?

[Slade]

Have you tried changing that Plug?

[mth5044]

I don't know, but where did you get that enclosure?! That is wonderful looking!

[richon]

Have you tried changing that Plug?

what do you mean by changing the plug?  it is working fine (and doesn't cut the voltage with moving it)

I don't know, but where did you get that enclosure?! That is wonderful looking!

i've build it  (look here for the process   :   http://www.diystompboxes.com/smfforum/index.php?topic=81068.msg671011#msg671011   )

thanks

[rustypinto]

Try cutting off that portion of the tangled/ looped-up portion of the cable and re-solder it to the plug. Sounds like some kind of short.

[JKowalski]

I bet the wire/solder connection is damaged on your AC wire. It may work fine (the pedal) but it may have excessive resistance because of the break and I suppose that might be able to increase the bleedover from your LFO....

Bending the wire like that undoubtedly positions the wire so the broken part has a stronger connection

[MoltenVoltage]

I suspect its the stuffed bunny.  Try moving it slowly toward the pedal and see if it gets worse.

The fact that you have to coil the wire leads me to believe its RF interference.  Try using shielded wire inside if the bunny doesn't fix it.

[Andre]

Your wooden enclosure does not seem to be shielded.
Shielding the inside with aluminium or copper foil will probably solve the problem.

[richon]

Your wooden enclosure does not seem to be shielded.
Shielding the inside with aluminium or copper foil will probably solve the problem.

I thought the same way two days ago, this is why I shield it completly with copper foil, but it doesn't kill the buzzing.

could it be just the AC inducing the guitar cables? or something else?

[puretube]

You grounded the shielding?
(correct answer = YES)

[puretube]

could it be just the AC inducing the guitar cables? or something else?

Yes - try a different position of them vs. the power-supply-transformer
(same goals for the guitar itself...)

[richon]

You grounded the shielding?
(correct answer = YES)

the shield of the box makes contact with just one point to the aluminium top (which is grounded "guitar ground)