If the TS-590 uses only two roofing filters and has "the best receiver specs out there", then I speculate that it could be using an H-Mode mixer, that the roofers exhibit better than average in-passband and skirt IIP3 followed by a decent "strong" IF, plus a LO whose phase noise is suitably low e.g. -145 dbc/Hz at 1 kHz offset.
If they have gone down this route and if they have paid attention to important details such as core sizes and mix, then with the 500 Hz roofer in line we might be seeing spurious free IMDDR3 figures of 120db at spacings of 1kHz, and a HF noise figure of 9-10db without a preamp, based on actual measurements made on a living "H-Mode" receiver. 73, Geoff GM4ESD From: "William Ravenel" <[email protected]> Sent: Sunday, May 16, 2010 1:24 AM >I talked to a Kenwood rep at Dayton this morning. He said the TS-590 would >have the best receiver specs out there. I asked if it would beat the K3 and >he said the TS-590 would have the best receiver specs out there. The radio >has an IF of 11MHz and two stock roofing filters - 2.8KHz and 500Hz - no >spare slots and no options. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
