Setup

Commercial instruments:

Many instruments and equipments (AFM, PLL, amplifiers and etc.) are commercially available for Akiyama-Probe operation. They are very reliable and highly recommended to use.

Build your own setup with analog electronics:

A self-oscillation circuit can be built with some OP-amps. In a simple case, the PLL can be outside of the self-oscillation loop and works in a passive mode. If a single chip PLL (e.g., 4046) is used, a complete setup can be built with a low budget. If a higher resolution is required in this configuration, the simple PLL can be replaced with a more accurate

commercial PLL without any major modification of the setup.

M. Ferrara, Nanotechnology 14, 427–432 (2003)

J. Jersch, et al., Rev. Sci. Instrum. 77, 083701 (2006)
H.-P. Rust, et al ., Rev. Sci. Instrum. 77, 043710 (2006)

Laboratory standard instruments + minimum analog electronics:

One can make a high resolution “self-oscillation + PLL” setup with two standard laboratory instruments (lock-in amplifier and frequency synthesizer) and a very simple analog circuit. The analog circuit with a few OP-amps forms a proportional-integral gain controller.

J. Rychen, et al., Rev. Sci. Instrum. 70, 2765 (1999)