Helical is a graphics-intensive bandpass filter design and analysis program based on the helical resonator. Main features: - The program designs bandpass filters with a selection of the order from 2 to 12, odd or even. - Center frequency, bandwidth, and passband ripple are all adjustable. The ripple value may be set to zero for a Butterworth response.
This program is designed to facilitate the design of PI and PI-L networks. Main features: - The design screen accepts inputs for the operating frequency, the load as seen by the final amplifier tube *, the intermediate impedance if the L-network is to be used, the output load value and the Q value for the PI-network.
OptLowpass™ is a specialized program written to expedite the design of transmitter output lowpass filters, especially for the HF amateur radio bands. The design page shows the schematic of the filter as designed and a plot of the responses of that filter (both transmission and reflection).
This graphics-intensive program is a valuable transmission-line calculator for both advanced and beginning users. Based on the venerable and highly intuitive Smith chart, it provides high-accuracy computations without recourse to paper, compass or straightedge.
This graphics-intensive program designs and analyzes active quadrature ("90-degree") networks for use in SSB transmitters and receivers. QuadNet is a 32-bit Windows program to design and analyze active quadrature networks. Plug in the values for a published design to see how it works.
This program uses the multiple-feedback scheme; it offers analysis in addition to design and tuning of the various components. And, most uncommon in such programs, it includes correction for the real-world opamp GBW. Writes ready-to-run LTspice schematics.
This graphics-intensive program reveals the load on the output of a matching-network, based on measurements of the components in that network. Adjust the network (tuner) for a flat input, measure or look up the network component values and you will immediately see the R and jX values of the load on the network.
Download a program which can be used to quickly design the RF lowpass filter used in the BITX (or other transceivers that have 50-ohm filters). The program is free to use for personal purpose and can be installed on all major windows platforms without paying a cent.
Download the active lowpass filter designer. This program uses the Salen-Key scheme; it offers analysis in addition to design and tuning of the various components. This program is free to use. It has been also categorized as "other" software from the current website but it runs fine.
Download a program which can assist in setting the component values for the BITX transceiver VFO. Tonne Software provides this program to be used freely for own personal use and also this program ca be used with ease because of its simple and intuitive interface.