Those who have both an Elecraft N-Gen and a KX1 have everything needed except the bridge elements to construct and use a relatively compact version of that Improved Noise Bridge described by John Grebenkemper in that August 1989 QST article.
The N-gen is the noise source and the KX1 can serve as the detector - listen for the null. Of course, it is easy to construct the noise generator, so those with only a portable receiver like the KX1 can have an accurate impedance meter once it is calibrated. Detectors other than a receiver can also be used - an AD8307 based power meter should work just fine and fit into a small case. The 'disadvantage' of the noise bridge is there are two knobs to deal with, but when a deep null is achieved one can read both the resistive and the reactive component of the unknown impedance. 73, Don W3FPR > -----Original Message----- > Dave G3YMC wrote: > > > I would also make a plug for a noise bridge. I built the one by KI6WX > > which appeared in QST in August 1989 (available to download from the > > ARRL site). If you have a suitable portable rig to couple to it does > > most of what the fancy analysers can do at a fraction of the cost. > > It should not be too difficult to design a fairly simple receiver > drawing a > small amount of current to be enclosed with a noise bridge to > make an 'easy > to carry' instrument. Top of head thinking. > > 73, > Geoff > GM4ESD > > -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.446 / Virus Database: 268.18.11/721 - Release Date: 3/13/2007 4:51 PM _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
