[Kenwood] SM-220 VS SM-230 etc etc

[WD8ARZ]

The impression made from a lot of posts over the years, has been that the 
solid state version of the SM-220, the SM-230, did not perform as well as 
expected for a newer more expensive scope / panadapter. There were a lot of 
complaints about drift with the 230. Many preferred the tube version, SM-220 
over the replacement solid state version.

No mistake about it, neither of these pieces of equipment were ever intended 
to be compared to commercial spectrum scopes or panadapters.

However in the amateur hobby world, they are great visual asset to those 
that use them to expand their situational awareness of what is going on 
around the frequency that they are listening to, or tuning through. It 
virtually opens up a bandwidth of information that exceeds what is being 
heard / seen at the speaker output. That this is an asset is undeniable to 
those that integrates the big picture a panadapter display provides. It is 
refreshing to see this feature showing up in more and more new rigs.

Also note that from time to time there are comments about software that 
tunes a rig's vfo and plots audio activity per frequency scanned on a 
computer screen. The resultant display is not very representative of real 
time situation. For fast results, large gaps are missed when scanning. For 
more detail and finer frequency plotting, the time it takes to do the scan, 
distorts the real time reality of what is going on considerably. The display 
is a result of many slices of time, spread across the display, as it takes a 
lot of time to scan the band this way. The best way to go is in real time, 
is to use panadapters / spectrum scopes tapped into early stage in the 
receivers I.F. before filters narrow down the usable range.

73 from Bill - WD8ARZ