In a message dated 16/03/05 22:48:02 GMT Standard Time, [EMAIL PROTECTED] writes:
The K2's I've tested fall down on LO phase noise performance. Also note that the K2 measurements on the Sherwood web site state that the receiver performance is limited by phase noise. I agree the RX works very well, but I've attracted comments on the air (when running QRO) re transmitted phase noise. ------------------------------------------------ I wonder if there is an obsession with numbers. To place the matter in perspective, the Sherwood Engineering web site does list the K2 which is serial #3170 or about 2 years old? as being the 7th from the top of all the ham radio receivers tested. The aspect of the effects of phase noise being only one of many parameters that determine the final result. I would presume that to measure phase noise needs the resources of a well equipped professional lab. Whilst personally I am well equipped to carry out servicing of radios from HF through to UHF, cannot even really scratch the surface in terms of measuring phase noise. The professional communications systems servicing organisation I worked for despite being well equipped for testing from HF though to microwave in the field had little that could be used seriously for testing phase noise except for probably some rather expensive HP spectrum analysers that were issued only recently to maintain a new 8GHz digital microwave system. Before slagging the K2 one should take more seriously what it represents in terms of outlay, costing only a fraction of cheapest HF transceivers available on the market. Admittedly you have to build it yourself, but still the performance of the K2 as what it was primarily designed for, a QRP CW transceiver takes a heck of a lot of beating. There are shortcoming that occur with the additional added components, though even these have been mitigated by later modifications. Do the persons reporting phase noise on K2 TX really know what they are talking about or just pushing out some mumbo jumbo that just happens to be the popular quotation of the day? To be frank most hams including myself would probably not be be aware what phase noise is even if it jumped out and bit them. Bob, G3VVT K2 #4168 _______________________________________________ Elecraft mailing list Post to: [email protected] 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
