996XT --> 996P2 IF changes?

[FeedForward]

That's the part that is really interesting. The 2 possibilities seem to be that 1) a Chinese company makes the same part at a lower price (and unknown quality) or 2) someone invented an IF strip on a single IC. Some of us remember when TV sets consisted of many transformer-tuned IF stages that had to be tweaked to give the correct passband shape. Then SAW filters came along and overnight made all those tuned circuits and manual alignment unnecessary.

It isn't just the one 450KHz filter in the Mu-Rata catalog that was dropped. Every filter below about 2MHz has been dropped. 455K IF strips suddenly go out of style? There's an interesting story here if the right person can fill in the blanks.

FF

 

[jonwienke]

SDR is replacing physical narrowband IF filters. It's easier to change a software parameter than physically switch filters, especially when doing extra-narrow channels like NXDN uses.

 

[FeedForward]

That is true. It is hard to keep up with advancements in receiver design. I'm not sure that I believe that digital everything is a step forward. But, it may solve some difficult problems like wide frequency coverage in scanners. Here is one such IF on a chip is the AD9670.

Going back a few posts, I'll just point out that no literature other than manufacturer's advertising makes claims about digital communication systems having low distortion audio. Communications equipment has nothing to do with high fidelity. Replace that word with "intelligibility". These two are not the same thing.

FF