I have Radcom in front of me. The editor has two reviews, the K3 and a new Alinco hand held. I suppose it shows the state of amateur radio in the UK that the hand held makes the front cover. The K3 reviews very well indeed.
So... to your figures. The 500Hz filter is 8 dB worse than the 2.7 kHz filter out of band but at close spacings. According to the review it suffers non-linearites not noted in the 2.7kHz stock filter nor the 8 pole INRAD the 400Hz filter. These showed odd properties with tone spacing that makes me think it was the DSP responding to the wider skirts of the 5 pole 500Hz filter but maybe that particular filter had a fault, it happens with crystals. Even so 88 dB dynamic range at 2kHz is not at all bad. I am sure the experts can explain this behaviour but for now I think it might be better to order an 8 pole 400Hz filter than a 5 pole 500Hz one - you will be able to sleep better. Mike Douglas G. Bonett wrote: > > The numbers reported below are close to what I would expect if the 2.7 kHz > and > 500 Hz column labels were accidentally switched. Typo maybe? > > Doug N0HH > > > ========================================================================= > Yes something isn´t right. This was his measurements: > > CLOSE-IN INTERMODULATION ON 7MHz band,500Hz bandwidth, CW preamp off > > 2.7 kHz roofing 1.8 kHz roofing 500 Hz roofing > 2kHz +19dBm 101dB +12.5dBm 96dB +2.5dBm 88dB > 3kHz +19dBm 101dB +12.5dBm 96dB +2.5dBm 88dB > 5kHz +22dBm 103dB +12.5dBm 96dB +8.5dBm 92dB > 7kHz +22dBm 103dB +12.5dBm 96dB +13dBm 95dB > 10kHz +22dBm 103dB +12.5dBm 96dB +17.5dBm 98dB > 15kHz +22dBm 103dB +12.5dBm 96dB +22dBm 101dB > 20kHz +22dBm 103dB +12.5dBm 96dB +25dBm 103dB > 30kHz +22dBm 103dB +12.5dBm 96dB +26.5dBm 104dB > 40kHz +22dBm 103dB +12.5dBm 96dB +27dBm 104dB > 50kHz +22dBm 103dB +12.5dBm 96dB +27dBm 104dB > > > > _______________________________________________ > 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 > > -- View this message in context: http://www.nabble.com/RSGB-RadCom-K3-review-posted-on-RSGB-Members-web-page-tp17988333p17988830.html Sent from the Elecraft mailing list archive at Nabble.com. _______________________________________________ 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
