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Pedal board HELL

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2/25/2000 4:53 PM

Pedal board HELL

OK,

I bought an SKB pedal board with power supply built in (actually it uses a wall wart to deliver power).

My first problem is hum. After trying the Anderton 1000uF/100 ohm resistor filter trick on the adaptor, I now get extreme squealing with my wah and FET preamp. I mean total oscillation. OK, yeah, I will remove the filter and that should fix that problem - but why is this happening? My Shaka 3 is fine - quiet as a mouse.

My 2nd and most serious problem is HUM. I traced it down to the Memory man deluxe (which is a 3 prong thing).

Here is the signal chain:

Buffer->Wah->Shaka 3->Fet Preamp->Volume Pedal->Memory Man

If I disconnect the Memory Man Deluxe from the signal chain - all is OK. (Except for the oscillation - which I guess will go away when I remove the filter from the Adaptor).

Can you give me some suggestions on how to kill this rather loud hum??

Of course I never had this problem when I ran with batteries. Only when I started using the power supply with the SKB.

Even if I unplug the guitar and have no signal going in, the combination of memory man causes hum. As soon as I unplug it from the signal chain, the hum goes away.

Should I try bypassing the ground pin on the memory man? Somehow this doesn't sound right...

Thanks,

Aron

2/25/2000 5:12 PM

Aron is the memory man plugged into the same outlet that the amp is? If it is NOT you could be on a different phase leg of the house power plug it into the same one and see what happens. In the US most homes have 220v ac in Two out of phase hots and a ground Some correct me if I am wrong here.

Did the older EH effects use a 2 prong plug!!!! I sounds like the jack grounds are connected to the plug ground.

2/25/2000 5:20 PM
aron	AMP, Pedal Board and Memory man into SAME outlet. >Did the older EH effects use a 2 prong plug Yes, the older one had 2 prongs. Why? How can I kill this hum "safely"? Aron

2/25/2000 8:17 PM
Joe Fuzz	I believe what he's saying is: Unplug the EH. Turn the plug around. Plug it back in. Did this help?

2/25/2000 8:51 PM
Gus	As a TEST plug the 3 prong into a adapter 2 prong with wire for the ground. The hum should then go away if it does then finding the safe way to wire up the system is whats left to do.

2/27/2000 11:05 AM

Well, darn it. The hum is fixed. I made that cord with the shield disconnected and it didn't help at all. After all sorts of fiddling, I simply connected a 9V battery to the board and the hum was completely gone.

To make a long story short, I went to Radio Shack, got one of those 8 AA battery holders and wired it up.

HUM gone, the only problem is that my FET preamp is oscillating now. :-(

:-(

Well, at least the board is useable.

Aron

3/7/2000 12:51 AM

Gus,

I looked into my Memory Man and yeah, as far as I can tell, the chassis ground is connected to the ground pin. I will test with a multimeter to make sure.

I have verified that the Memory Man Deluxe reissue DOES induce hum into the system. I have not lifted the ground yet, but will soon (gotta buy a 2-3 adapter).

If this fixes the problem (hum), then how can I rewire the Memory Man to get rid of the hum. How do I wire it "correctly".

Thanks,

Aron

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