Veroboard design for Ilitch trimpot PCB (HowTo)

harmaes

Well-known member
Can someone help me with how to create a veroboard design from the schematic below?
This is the trimpot PCB for an Ilitch backplate denoiser coil that I'd like to create on veroboard. On the left the BPNCS (back plate noise coil) is shown which has a resistance of about 335-360 ohm.

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I created 2 with 47nf and 5k and 10k trimpots to see how these work (caps are between lugs 2 and 3 of the trimpots).
I have the neck and middle single coils now connected straight on the Ilitch backplate which works well (ground to one side and the other side of the backplate to ground). I will see if this will reduce the static a little I get when releasing my hands from the guitar and if it can improve the residu noise.

So as I understood the working of the trimpot is that it can reduce the amount of noise coil (dial it in). So why 10k resistance and around 50nf?
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Here’s the patent https://patentimages.storage.googleapis.com/4c/92/3b/fa509bbe1795aa/US20050204905A1.pdf that describes the trimpot/cap as follows:

A resistors capacitors circuit network connected in parallel with the Said large noise picking coil to optimize the level, frequency range and Secure an effective noise cancellation.

The basic electric schematic on FIG. 5 demon Strates the way the Magnetic pickup device for a Stringed musical instrument with large free shape low impedance coil for noise cancellation (23) is electrically connected. The musical instrument is equipped with one Volume (15) and one Tone (13) control potentiometers and an Output jack (16). Along with the standard Volume (15) and Tone (13) (250 to 1000 KOhms potentiometers), additional resistors and capacitors network is provided.
The level of the created noise Signal by the large noise picking coil (12) is controlled by the noise signal level control device (18), which is a trim-pot that adjusts the level of the noise electric Signal in order to have an optimal noise cancellation for the entire device.
The frequency response control device (20) of the noise Signals is a trim-pot that controls the frequency range of the noise electric Signal created by the large noise picking coil (12), in order to have an optimal noise cancellation
.
The Start wire terminal of the large noise picking coil (12) is electrically connected to the electrical ground terminal of the musical instrument (17). The End wire terminal of the large noise picking coil (12) is electrically connected to the Start wire terminal of the signal picking coil (11). The direction of winding of the large noise picking coil (12) is made in a way that Secures the phase of the noise electric Signal created inside the large noise picking coil to have an opposite phase with the noise electric Signal created by the Signal picking coil (11).

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