Most commercial diffraction grating based spectroscopic devices employ entrance slit and optics based on the conventional Czerny-Turner (CT) configuration. A study was undertaken to design and develop a novel lab-scale electronic slitless spectrograph (ESS). The developed ESS has a tuneable spectral detectable range from approximately 450-1100 nm and a scanning speed of 0.7 s per spectrum. It works under reflectance mode with external illumination. System design employed a fibre optic waveguide as the probe, several focusing and collimating lenses, a plane reflection diffraction grating and a linear array charge-coupled device (CCD) detector. A method using a single-mode diode laser to calibrate the wavelength and pixel relationship was applied to obtain a least-square regression equation. An argon lamp was used to validate the calibrated wavelength equation and a maximum wavelength error of 1.95 nm was reported. A procedure to estimate the instrumental optical band-pass using laser spectra with a limited number of sampling points was examined. An optical band-pass expressed as full-width-at-half-maximum (FWHM) of 6.71 nm was estimated using the proposed method on the spectrum of the single-mode diode laser. The test results suggest that the developed ESS system has the potential to serve as a rugged and cost-effective spectroscopic device for routine inspection. The prototype consists of no moving parts and the complete assembly measures 30 cm × 25 cm × 15 cm, which can be greatly reduced upon further development.