-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I would be the first to order a unit Jack
Theres some excellent plotting software just waiting for a S meter interface as you describe. http://www.g4hfq.co.uk/plphelp/plphelp.htm Theres little alternative available for those seeking a accurate S meter on a ham radio transceiver. Besides i see no harm as hams being professional in our approach to signal measurements. After all who would buy any test instrument today if it had a 200% error in accuracy, but thats what we have today in every radio receiver and transceiver. Craig VK3HE On Tue, 17 Oct 2006 02:30:47 -0700 Jack Smith <[EMAIL PROTECTED]> wrote: >One possibility for an "add in" S-meter module would be an AD8307 >log >amp module paralleling the IF amplifier's input. This will give >you an >honest 80 to 90 dB linear output (db in, linear output), if you >can >manage the shielding, and close to 100 dB if you don't mind a bit >of >non-linearity at the extremes. To avoid loading down the IF amp >input, >you probably need a isolation amplifier. > >And, of course, there's always a concern when mucking about inside >the >signal chain. The buffer amplifier I offer with my Z90 digital >panadapter samples the K2's IF at an earlier point, just after the > >2N5109 post-mixer amplifier, but the design could easily be used >to >sample after the filters. (The Z90 uses an AD8307 log amp >detector, so I >have some experience with it.) > >The log amp's output could then drive an external moving coil >meter, or >it could be digitized via an ADC and brought out on a RS-232 >compatible >port for other purposes. Serial output would require an on-board >PIC and >would have to carefully constructed to avoid introducing unwanted >noise >into the K2, but an all-analog solution would be simple enough if >the >output device is to be a D'Arsonval meter movement. > >If there's a groundswell of demand for such a beast I will >consider it >as a future kit offering. > > >Jack K8ZOA >www.cliftonlaboratories.com > > > >[EMAIL PROTECTED] wrote: >> -----BEGIN PGP SIGNED MESSAGE----- >> Hash: SHA1 >> >> I also looked for a solution to the S meter calibration problem. >I >> discussed the problem with Greg Ordy w8wwv Author of the great >> program called S meter light. Unfortunately the K2 does not >return >> 8 data bits via the serial port so the calibration accuracy >would >> be close to useless. If the K2 did return 8 data bits you could >> obtain 0.1 db accuracy using Gregs program. 8 data bits >returned >> via the data port is available on the 756PRO and several other >> radios. Elecraft cloned the Kenwood command set which returns 4 >or >> 5 bits or something like that. >> >> Maybe Elecraft would consider this as a future external option >for >> the K2 . It certainly would be a first for a ham radio, that is >> having a inbuilt calibrated S meter. The crunched up S meter >> bargraph is highly annoying and close to useless on the k2. >> >> Craig >> VK3HE >> -----BEGIN PGP SIGNATURE----- >> Note: This signature can be verified at >https://www.hushtools.com/verify >> Version: Hush 2.5 >> >> >wpwEAQECAAYFAkU0nagACgkQFO3Fz3YpTj13zwQAglTPukBl74ltyvgFugyGzdWSorR >1 >> >cS6JbAj4LN7RgzF/A1teW2plQNddqiYYjd20Qbd6vRgU6CQpuj3F9Y7k78hbNF4jk4Y >Q >> >lv27yGd6QsTmCndTSyN4rwhona3eORFaFhJxV+0w8udI9Ci/I5A2HwXU1BIi611sMNT >k >> CMNBQx4= >> =6fqa >> -----END PGP SIGNATURE----- >> >> >> >> >> Concerned about your privacy? Instantly send FREE secure email, >no account required >> http://www.hushmail.com/send?l=480 >> >> Get the best prices on SSL certificates from Hushmail >> https://www.hushssl.com?l=485 >> >> _______________________________________________ >> Elecraft mailing list >> Post to: [email protected] >> 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 >> >> >> -----BEGIN PGP SIGNATURE----- Note: This signature can be verified at https://www.hushtools.com/verify Version: Hush 2.5 wpwEAQECAAYFAkU16CMACgkQFO3Fz3YpTj2/oAQAgXL632lZQzAXBJ+eSNntKH/Xce53 DQuR+u5Qir85qmP18l6fwK7NznpXh1lo9UpuF0UBCfxfXKPjKzXg+YkE17GZI1e+16Pb cPBBNaXiP/vTq6ctkF3+jdLRbgoWtnDY2LCoaQYlojEZsMI1ee4jbhAKE6AtipkLaoUT 2n9war0= =NSwj -----END PGP SIGNATURE----- Concerned about your privacy? Instantly send FREE secure email, no account required http://www.hushmail.com/send?l=480 Get the best prices on SSL certificates from Hushmail https://www.hushssl.com?l=485 _______________________________________________ Elecraft mailing list Post to: [email protected] 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
