John, These articles should answer any questions you might have:
<www.mrtmag.com/mag/radio_testing_repeater_sensitivity/> <www.repeater-builder.com/tech-info/effectivesens.html> <www.repeater-builder.com/measuring-sensitivity/measuring-sensitivity.html> <www.repeater-builder.com/projects/bird43sampler.html> <www.repeater-builder.com/antenna/deaf.html> Measuring effective sensitivity and the degree of desense is best done with a service monitor, but useful measurements can be made with a calibrated signal generator and a spectrum analyzer. It is important to determine whether the desense is caused by your repeater's transmitter or by another transmitter. The corrective actions differ, depending upon the source. The original article in MRT (Mobile Radio Technology) Magazine included some great step-by-step photos showing how to build an ISO-TEE, but the online version of that article (above) omitted the photos. :-( 73, Eric Lemmon WB6FLY -----Original Message----- From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of John Transue Sent: Wednesday, July 09, 2008 12:18 PM To: [email protected] Subject: [Repeater-Builder] Measuring Desense <<...>> Ron, Don, Mark, and others, The attachment shows how I think I should connect things to measure desense. I would use the Bird with sampling coupler in place of the iso tee shown. Does this appear to be a correct way to measure desense? Also, I can replace the feed line and antenna with a dummy load as Ron has explained. John AF4PD
