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EHX Small Clone Plop Noise Fix

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This modification fixes the "pop" you hear when you engage the EHX Small Clone for the first time. The components removed in the following steps were needed for switching in previous versions of small clone before EHX introduced a 3PDT footswitch, thus, removing them DOES NOT affect the tone. It is also worth noting the adding 1M resistors at the input and output of the effect will not fix this problem. Steps: Remove the resistor R24 (1Meg) Remove the resistor R25 (10k) Remove the capacitor C16 (0.05u) Remove the diode D2 (1N4148) Remove the JFET transistor Q4 (2SK30) Jumper (D) and (S) on the location where Q4 was installed. Rewire the 3PDT as illustrated below (last picture). This wiring incorporates both effect input and output grounding during bypass. Components removed and jumper wire installed. The wire connects the chorus effected signal to the output mixer and replaces the functionality of the JFET transistor. Overview of the 3PDT connections (I had to change some wir...
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Boss BF2 Calibration

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Here is a guide I put together to calibrate the BF2. This is based on the BF2 service manual floating around the internet. Reference points for the measurements: Step 1: Set the Manual and Depth to 0% Connect probe at TP-1 Adjust VR7 so that the period of the measured signal is 25us. It should look like this. Now turn the Manual 100%. The period of the measured signal should be 2us plus/minus 20%. The same plot but expanded in time. Step 2: Set Depth and Res to 0% Connect a 220 Hz, 0dBm sine wave. With a 600 Ohm generator this corresponds to a voltage of 0.775 V. This is the input signal. Connect the oscilloscope probe to the emitter of Q3. Adjust VR6 so that there is no clipping of the measured signal while turning the Manual from 0% to 100%. The Manual set to 0% The Manual set to 100% Negative clipping should look like this. Positive clipping should look like this. Step 3: Set the Manual and Depth to 0% and Res to 100% Connect a short to the input Connect the output to the oscillosco...
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Boss SD1 Bypass Bleed Fix

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I tried this bleed fix for the SD1 today and it works like a "charm".  The idea is based on the concept I found by studying the DS1 circuit. I have used an n-channel JFET (2N5457) with measured Vp = 1.3V and IDSS = 2 mA. The circuit modification: The bleed-fix implementation in stripboard (3 rows by 3 columns): Pictures of the build and installation: The stripboard is installed in the position of C2. The longer leg of the capacitor  is installed in the pad of C2 closer to the opamp. The longer leg of the transistor is installed in the pad of C2 the connects to R3 (check trace underneath). Make sure the stripboard underside doesn't touch any other components on the board. If you have any questions let me know.
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