How to get Kay tremolo perf build to unity?

[gsr]

Hello, I just completed a build of a Kay tremolo on perf board. I like the effect a lot. It is a "repeat percussion/helicopter chop type of thing, but it is much lower volume when engaged. I am wondering if anyone has built it and encountered the same thing. Also, has anyone devised a fix. I can follow a recipe, but am by no means an electrical engineer/designer. i built from the "oh Kay tremolo" layout (link below), which is a modified version of the project on the General Guitar Gadgets site. Any help would be greatly appreciated. Glen

OhKay Tremolo

[gsr]

If I increase R-13 at the output, will that bleed less signal to ground? I'm thinking maybe 100k instead of 47k. Any input is appreciated. Glen

[guitician]

Right under the .22uf cap there is a 47k ohm resistor. You may have an issue with the transistors gains being different. You may have to find the right types of transistors to get unity. Increasing the 47k to 100k may not amount to much more output.

[guitician]

Here is a tread about the Kay T-1. It seems that the 1K pot is really a 5K. Did you use 1k?
Print Page - Kay Tremolo voltages and info

[gsr]

I used 5k. I found all the parts listed for the "Oh Kay" layout. I tried the 100k resistor swap and it got me maybe 1/2 way to unity. I also tied my led + to Q4 collector and got the cool flashing led. Do you think increasing the 100k even more will help, or is there a point where bad things could result?

[Mark Hammer]

Here is a tread about the Kay T-1. It seems that the 1K pot is really a 5K. Did you use 1k?
Print Page - Kay Tremolo voltages and info

That pot adjusts the speed of the LFO. It should not have any impact on the output level.

Note that the 100k to ground near the output, and the 100k that feeds the input to output, form an attenuator. Perhaps if the value of the series 100k is reduced, or the 100k to ground is increased, or both, that will result in less attenuation of the signal.

[guitician]

I used 5k. I found all the parts listed for the "Oh Kay" layout. I tried the 100k resistor swap and it got me maybe 1/2 way to unity. I also tied my led + to Q4 collector and got the cool flashing led. Do you think increasing the 100k even more will help, or is there a point where bad things could result?

You may be able to remove the resistor completely, depending upon whether or not the device your running this into has a DC path to ground, which most amps do. Just as a test to see how much more output you get. Then go from there.

[guitician]

That pot adjusts the speed of the LFO. It should not have any impact on the output level.

I didn't say that it did. Just noticed an interesting thread he could refer to. Also, in that tread they posted transistor types and voltages he could reference.

[gsr]

I increased the 100k to ground to 220k and decreased the 100k input/output resistor to 50k and it is almost dead on! Many thanks to Mark Hammer and Guitician. I now have a very nice, usable trem pedal that goes from warm smooth to helicopter chop. Thanks also to Aron Nelson for his generous posting of the layout. Glen

[Mark Hammer]

Excellent! Thanks for the detailed feedback. That will be useful to others.