Thomas crybaby mod question

[keith71]

Hi every one here,

I got a nice Thomas Organ wah from the seventies with a stack of dime inductor, I modded it for true bypass and it works really nice.
That said, I never liked using battery, so I plan to mod it for a 9V DC input jack. Do you think I can wire the dc jack directly where the battery wire goes, or do I need to install kind of filtering circuit ?

[alderbody]

although i don't think there's a need for a filter, i'm really interesed to see what the experts will recommend.

[RedHouse]

Direct works.

Better if you have a good regulated power source.

I get great results using LM7809 regulators and adding a 1k resistor between the regulator and the wah, helps raise the impedance a little.

[Paul Marossy]

I would use at least a 220uF cap across the power supply if you're going to use a wall wart for your power supply.

[ilponiz]

i added a DC power jack to my Thomas Organ cry baby wah and now i got a buzzing wah when using an unregulated ps.

what kind of filtering will you recommend?
is there a ground connection scheme that i should use?

thanks

poniz

[yeeshkul]

Use the filter that is inside CB  GCB 95:  220u||100n||diode (1N400x)
At least this one is tested to be working fine. Some filters use 10n instead of 100n. The small cap is there to shunt high frequency hum. Stick the bundle right across the DC socket. Do not underestimate the diode. If you still can hear the hum add 100ohm res in series with the power and/or go for 330u instead of 220u. If this doesn't help pick another wall wart.