The paper demonstrates the telecalibration capabilities of pigsar, the national standard for natural gases at high pressure of Germany. The telecalibration tool was developed in order to give PTB an efficient access to the on-going calibrations at pigsar. It can be considered as a new tool for metrology to maintain and supervise the dissemination of the units volume and mass of natural gases under high pressures. Furthermore, telecalibration is a necessary tool and issue to provide for PTB-certificates based on the harmonized reference value for high-press natural gases as agreed between between NMI-VSL and PTB.
After a short introduction explaining the metrological situation, an overview is given about the technology and features of the software. The telecalibration software used by PTB is identical to the software used at the national lab pigsar for the daily calibrations. Due to security and safety reasons, not all options and functions are available at PTB. The handling of the software is based on different software screens necessary to visualize the process of calibration and to supervise a gas meter under test respectively. The screens shown in the paper are test results of a “watch dog test” carried out to supervise the harmonization procedure of the natural gas cubic meter between PTB and NMi.

A theoretical model for gas-liquid annular-dispersed flow through a Venturi meter is reported. It is based on an earlier model developed for Venturi scrubbers. Changes implemented are based on new research and on the different physics between the two cases. The predictions of the model have been tested using information from recent experiments on Venturi meters employed for measuring wet gas flows with liquid volume fraction up to 10%. The model gives good predictions.

High speed ADCs are considered more and more by ADC manufacturers. The aim of such components is that they are to be used in applications such as high speed data acquisition devices, digital oscilloscopes, digital RF/IF signal processing, digital RF down conversion... The application we target in this research is the last one, digital RF down conversion, by the use of a high speed ADC (8 bits – 1 GSPS) in a radar receiver. In this article, we present a brief comparison between two kinds of radar receiver architectures : the superheterodyne and the expected one. We also present the method to characterise the ADC working in radar mode and the conclusion of the research.

This paper presents a preliminary study aimed to optimize the signal characteristics of an optical indoor wireless communication system for telemedicine and mobile user applications. Specifically, detected signals associated with experimental geometries based on line-of-sight (LOS)-point-to-point-optical link and line-of-sight (LOS)-point-to-point-parallel to a surface-optical links are shown. In addition, applications of wavelet transform algorithms aimed to reduce the noise components associated with the detected signal are presented.

The paper demonstrates virtual instrument software that performs simple and fast testing of any PC sound card with correctly preinstalled Windows driver in waveform recorder applications related to IEEE Std 1057, drafts IEEE Std. 1241 and DYNAD. In addition to the visualisation of recorded signal patterns in time and spectral domain, the software directly determines various basic parameters of input analog channels e.g. effective number of bits, THD, THD+noise, SINAD, etc. The parameter determination is performed both in spectral and time domains to compare the achieved results. A modified 4 parameters sine fit method was implemented with respect to soundblaster test nature. The software was developed in LabWindows/CVI (C language) with implementation of lowlevel Win32 API multimedia functions. The authors’ intention is to apply the software for computer component vendors and in educational demonstration of ADC testing principles. The paper contains also some example of achieved results from testing some soundblasters.