One of the posts that I found confusing and prompted a reply from me was from Eric: http://mailman.qth.net/pipermail/elecraft/2009-December/122284.html
Specifically, the 2nd sentence. ------------------------ BUT NOW I've finally put it all together (Okay, maybe I'm a bit slow). If you are also confused, I hope this helps (and I hope I've got it right). If you're not confused, stop reading now, unless you are Eric or Wayne in which case you may jump directly to the bottom. The DSP board revision is modifying component values on the board itself to expand the low frequency (audio) response. Elecraft is using different component changes than those offered by W9AC. If you buy the upgraded DSP board, you get the Elecraft changes which "enhance the low end of audio" (more bass). On top of that, there is also the LPF board. This add-on is just what it says, a Low Pass Filter. In other words, it knocks out the higher audio frequencies, which may contains various artifacts ranging in the 5kc to 14kc range (not a range of interest to those involved in ham communications), while "passing" the low frequency stuff. If you do not buy the DSP board upgrade, but add ONLY the LPF board on your own, you will cut-off the higher frequency artifacts (if any). If this is the "noise" some commented on, this may help reduce or eliminate that. If you want to extend the low frequency (bass) elements, you need to modify the components on the DSP board. You can either DIY via W9AC or buy it from Elecraft. As a "bonus," if you buy the DSP BOARD UPGRADE (swap) from Elecraft, you get "both" = LPF "add on board" to kill the high freq junk AND the extended low freq response due to modified component values on the DSP board. If you are like me (and many others), you don't hear the high freq junk (hence, no need for the LPF) and you are already quite happy with the low freq response (how low a note do you want to hear?), and THEREFORE, won't buy the upgrade (either the entire board which includes the LPF board, or just the LPF) and won't implement the W9AC component mods either. Clearly, not everybody is "like me." I have to admit, this was a very tortuous email route to a fairly simple conclusion. The emails and announcements along the way were all very "choppy" and unless you already understood what was happening (imho), it did indeed seem confusing and perhaps even "conspiratory." Of course, having dealt with the Aptos guys and their emails for years, I knew it could not be the latter. ;-) MY SUGGESTION TO ELECRAFT: Besides offering the completed DSP upgrade, for those who are capable, also offer a "kit" which includes the replacement components for the DSP board. So the loyal owner would have three options: 1. Buy the completed updated DSP board with new component values on the board AND the LPF board (you already offer this). 2. Offer just the LPF board (you already do this) 3. Offer a kit which contains only the components to be swapped out on the ver B DSP boards (new). Whew! de Doug KR2Q ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
