No effect - Tonepad EA Tremolo

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No effect - Tonepad EA Tremolo

Postby WCraigConrey » 29 Apr 2011, 21:24

Hello all,
I just buttoned up a build of the EA Trem as per Tonepads board and diagram. I ended up with good bypass, and, when engaged, the level control works as a clean boost. No tremolo effect is present. Running an audioprobe presented no trem throughout the audio path, HOWEVER, there is a slight and subtle trem effect near the end of note decay. I know this occurs naturally, but it varies with the rate of the speed pot. (?????!!!)
To the FSB policemen, I see that this has occured in the EA Trem done by ROG, but those problems were cornered to LED orientation problem. I have no LED yet, and it will serve only as status.

I used massive (100V) caps for the NP 1 uFs, would this possibly hinder the signal? Also, I substituted a 1.2K resistor for the 1K at speed lug 2 to center 1uF. I will later post a picture of the build. Thanks to all who reply! It's what makes the board so grand!

Reference site:
http://tonepad.com/getFile.asp?id=130
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Re: No effect - Tonepad EA Tremolo

Postby reneshelle » 29 Apr 2011, 21:40

Does the depth knob do anything? I would check that for starters.

The audiosignal gets passed, that means that the problem (most likely) is to be found in the "Q2/Q3" (non-audio) area of the circuit. Try probing around a bit there and see what you find

I'm no EE but I think that your caps should be fine.
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Re: No effect - Tonepad EA Tremolo

Postby WCraigConrey » 29 Apr 2011, 22:23

No, the depth knob does nothing. I have the Q2 FET and the Q3 tranny oriented like the parts layout picture on the website. I soldered them directly on the board without sockets. I wonder if I could have superheated them. Does anyone know about what voltages should be present?
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Re: No effect - Tonepad EA Tremolo

Postby reneshelle » 30 Apr 2011, 17:03

Try a new q2... I've never build one so I can't measure voltages...

check pinouts for the fet
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Re: No effect - Tonepad EA Tremolo

Postby WCraigConrey » 04 May 2011, 03:06

I have found two bad joints so far. The traces have been coming delaminating from the board as I've pulled components to replace "maybebads." It's time to etch a new board and try again later. Thanks Reneshelle for your ideas. This topic can be deleted.
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Re: No effect - Tonepad EA Tremolo

Postby andregarcia57 » 02 Jan 2012, 14:18

I also made some changes to solve problem of speed 10 no effect;
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