To All, For the benefit of those who do not subscribe to the SED newsgroup, here is a brief description of the binary sampler along with two significant advantages: -------------------------------------------------------------------- Conventional samplers for home brewers usually go to 1 GHz. The SD-32 sampler for the Tektronix 11801C mainframe goes to 50 GHz. The HP 110GHz oscilloscope costs around $1.3 Million USD, with a 10-bit resolution. Very impressive, and very expensive: https://www.youtube.com/watch?v=DXYje2B04xE I have invented a new sampling technology that promises 160 GHz bandwidth, yet is affordable to home experimenters. If you can afford an IPhone or IPad, you can afford this sampler. This technology is not pie-in-the-sky. I made a basic 5 GHz version for the University of Ludwigshafen, Germany, and they were very pleased with the results. This was the first prototype, and I have made significant improvements since then. The sampler offers substantial advantages over conventional samplers: 1. conventional diode samplers can have significant loss using multiple stages to acquire the sample, perhaps 40 dB or more. This degrades the SNR, especially for low-level signals. The new sampler has no such loss and operates on the input signal directly, giving maximum SNR. 2. conventional samplers produce samples that combine the actual signal plus noise. Averaging can improve the SNR up to a limit, where it takes too long to improve the SNR. The improvement is given by sqrt(N), where N is the number of samples. Improving the SNR means doubling the number of samples, and eventually the doubling takes too long to be practical. In addition, the signal can drift during long sampling times making the results useless. The new sampler bypasses this limit by restricting the amount of change that can occur in each sample, so the conventional equations no longer apply. It can easily recover signals buried in 30 dB of noise, which is impossible with conventional samplers. -------------------------------------------------------------------- I am attaching a paper I wrote in 2003 discussing the theory and results of the first working binary sampler. I have made significant improvements since then, which I will discuss later. I have got the binary sampler technology working in the phase domain in LTspice. This is a big deal, since it gives the same noise rejection as in the amplitude domain. This will have significant advantages in GPS timing recovery. In particular, to minimize the jitter caused by the sawtooth phase error due to misalignment of the local oscillator with the satellite carrier frequency. For example, see one of TVB's many analysis of a MG1613S GPS Receiver: http://www.leapsecond.com/pages/MG1613S/ (2010) Of course, this cannot eliminate the timing error caused by constant phase difference when the signals are aligned (hanging bridges), but I hope to be able to recover an error signal to apply to the local oscillator to keep the phase constant. More information soon. Mike