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Radium Springs things

Hi there,

I built a Radium Springs a little while back and some things seem a bit quirky.... The main thing is that the tremolo is hardly noticeable. When the pedal is at 100% wet and 0% dry I can hear that there is tremolo happening but it is so subtle that any amount of dry signal makes it inaudible. The tremolo amount also seems to be controlled by the mix knob which I guess is just an unfortunate design decision as I thought that is what the depth was for. The other thing I've noticed is that the pedal abruptly switches to 100% wet at the end of the pot and the there is a large volume difference between the effect and the dry. Perhaps I have a bad component that is causing the effect to be too low in volume?


Well-known member
the way the wet/dry mix control is working sounds wrong and you should have much more wet signal in the mix than you are describing. either the pot is the problem or the incoming wet signal is too low.

make sure you have the correct value pot for the wet/dry mix, and check resistances across and between the terminals on it at the 25%, 50% and 75% points in the rotation to see if it is working correctly. if the mix pot is OK, then you should start checking part values and connections between the the output of the FV-1 and the mix control.
Thanks for the suggestion. I've checked everything and all the components are correct. The pot is behaving perfectly fine except that it is reading 8k rather than 10k but it is actually as an 8k pot should. I.E. it is measuring 4k at 50% etc. I don't think being 8 instead of 10 would matter all that much right? Especially because it's maintaining the correct ratios.


Well-known member
Seems like you need to investigate the wet signal level. Check the schematic and use an audio probe.