Off List Reply Follows - copied to the reflector Hi Jeff. I don't have the schematics in front of me but some of the crystal filter capacitors were changed in the later revisions to widen the response from about 2.1 KC (actually measured about 1.9 at 6 dB down points on mine) to about 2.4 KC. These caps are a part of the xtal lattice filter and are identified on the schematic as CA, CB, etc.
The old "standard" was the approximate 2.1 kc width and the new "standard" is the 2.4 kc width (maybe it was 2.3 - something like that). As I recall, a couple of other changes were made - a couple of resistors and an electrolytic capacitor - and additionally, enhanced xtals were available and still are as "matched" sets. Just my 2 cents but I'd change the xtal lattice caps to the "new" values now during initial construction. Removing those caps is a real pain later - this from experience as I've done it a total of 3 times to get various widths. All in all, the 2.4 width is very nice! As for the matched xtal set, I did change out mine and noticed no difference at all. Others have reported that it did make a big difference. Hope that helps - 73 es have fun --Don N4HH K2/100/KAT100 #2028, etc, etc > > My question is regarding the current Rev. F. as compared to my Rev. D. I > noticed that some component values are different, but the board layout looks > the same. I assume that the values have been optimized. > > Is this an accurate assessment? Can I simply change the values to the Rev F > values? Should I just stick with the Rev D values that originally came in > my kit? > Jeff - VA3JFF > K2 #3375 > KX1 #631 > Canadian QRP Award: http://www3.sympatico.ca/wjhetherington/cqa.htm -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.300 / Virus Database: 265.8.3 - Release Date: 1/31/05 _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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
