Cortland, Thanks for the info. Can I ask what firmware version is on your 450?
Presumably the tx filter is implemented by DSP on these models and it may just be a software issue which in time may be fixed. The version here is 0194. Regarding the rx filtering I am quite happy with the rig. Using a software spectrum analyzer (MultiPSK) the rx passband looks fine. I had an FT-897D with both a 300Hz and 500Hz filter and while the 450 DSP CW filter is not quite as effective I still find it surprisingly good on CW and general receive. In fact at this point I feel it has a better receiver than the 897. Certainly the contour is a big help on some signals and the NR seems not quite as weird sounding as the 897 was. The manual notch is also very impressive and much more useful than the 897 auto notch. CAT control on the 450 is much better too, it is more responsive than the 897 and works very well with HRD and OmniRig. All in all I am quite happy with it and if one day a software update comes along and fixes the lumpy tx passband it will be a bonus. 73 Sholto KE7HPV Cortland Richmond wrote: > > > Hello Sholto, > > In the Yaesu FT-450 Yahoo group photo files there are a series of receive > BW scans I took with my 450, with a couple of 857 scans thrown in for > comparison. If it has a narrow CW filter, the 857 IMO wins on filtering > and its audio DPS works extremely well as an adjunct to accessory filters. > The 450's SSB response seems by comparison rather "peaky", just as the plot > linked here indicates for transmit. Unfortunately, the 450 lacks the > ability to move the carrier closer to the filter skirt. > > I have not done 450 output power measurements vs audio frequency, but it > sounds like a worthwhile experiment. I will say that where we use wider > modes for MARS, such as 1K MT63 and Olivia 1K 32 tone (very nice weak > signal performance) I have not noticed the 450 being less effective than a > Harris RF350 (300 Hz - 3000 Hz BW). But I have not looked, either! > > Cortland > KA5S > > > [Original Message] > > From: Sholto Fisher <sho...@probikekit. com > <mailto:sholto%40probikekit.com>> > > To: <digitalradio@ yahoogroups. com > <mailto:digitalradio%40yahoogroups.com>> > > Date: 1/8/2009 12:45:20 PM > > Subject: Re: [digitalradio] Re: FT-450 on digimodes > > > > Juergen, > > > > Thanks for doing the test. > > > > Now I am confused because I contacted Yaesu and sent them this graph of > > my measured transmit passband: > > > > http://www.projects andparts. com/misc/ ft-450tx. gif > <http://www.projectsandparts.com/misc/ft-450tx.gif> > > > > And this is what the engineer told me: > > > > "Your graph shows the typical audio roll off expected. The bass band > > deviation for the FT-450 is 300-2500. You would expect the dBWs to peak > .. > >
