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Last Update: Saturday, 28 January 2017


New! The 2-Tone Kit - A classic piece of test equipment redefined.

Our newest kit, a two tone test oscillator employing digital signal synthesis techiques to generate a low distortion composite audio test signal for SSB transmitter testing. The 2-Tone produces a 700Hz/1900Hz test signal with adjustable output level and tone balance which when connected to a transmitter audio input allows linearity to be inspected on an oscilloscope or spectrum analyzer. In addition to dual tone operation the 2-Tone can also generate a variable frequency single tone output for testing the transmitter's audio channel bandwidth. Visit the 2-Tone page for more information.

"Eden dsP" v1.3 PCBs now in stock

Double sided, silk screened PCBs to construct the DSP module. Supported by free software, this flexible design offers ideal route into DSP. Capable of operating at up to 70MIPS with the new dsPIC33E 16 bit processors, this easy to construct unit is suited to many audio and communications applications. This revised version incorporates several changes to enhance the versatility of this popular unit. Visit our DSP page for more information; DSP

Minifilter Audio Clips

We've had quite a few question about the Minifilter and in particular what it sounds like. Well now you can judge for yourself, we've posted some audio recordings at the bottom of the Minifilter page. Simply click on the links to play the sound clips.

"Eden dsP" Yahoo Group

Have you built or are you considering building an Eden dsP module? Then the Eden dsP Yahoo group is for you! The group features a forum for news support and exchange of ideas along with a files area offering code examples and projects. More details at;

"X-Lock" the FT101E!

Angelo Castellano, IK0BGG describes how to install and set up the X-Lock in the FT101E transceiver to give this classic radio a rock steady VFO. Read his article on the X-Lock Solutions page.

New The Minifilter DSP Audio Processor

This small DSP filter module packs 12 high performance audio filters along with an Auto-notch, Denoiser and an AF Power Amplifier making it ideal as a receiver upgrade of for use as a stand alone audio processor. Two groups of "brickwall" non ringing 501 tap FIR filters arranged as 6 "wide" and 6 "narrow", offer predefined bandwidths of 2400Hz (300 - 2700Hz) down to 200Hz (600Hz - 800Hz) providing a useful enhancement to audio and effective suppression of adjacent interference in the audio passband.

A highly effective fast auto-notch makes short work of multiple in band hetrodynes whilst preserving good speech quality. The denoiser reduces random noise greatly improving a noisy audio channel and easing listener fatique. A unique feature of the Minifilter kit is that it uses 0.1" pitch through hole parts throughout, bringing DSP contruction within the abilities of all!

See the Minifilter page for more details.

Ahora en espaņol! Con agradecimiento a Jon Iza, EA2SN.




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