Anytime. Glad to help Raj. 73 Greg AB7R
-----Original Message----- From: Rajiv Dewan, N2RD [mailto:[EMAIL PROTECTED] Sent: Monday, December 31, 2007 9:42 PM To: Greg Cc: [EMAIL PROTECTED]; Elecraft List Subject: Re: REF OSC Frequency Greg, You are right about the bold faced caution on Page 47 and indeed I waited long before doing the REF CAL, which I did using Method 2 with the cover closed. However, I am still surprised by the frequency excursion measured on start up. I did wait a lot longer and calibrated it using method 2, zero beating it with WWV. This was at ref cal value of 49,379,611, which is a lot closer to the frequency noted on the sheet that came with the TCXO - 49,379,964. With the ref cal set, I have re done VCO CAL and other calibrations. For now all seems to be as it should be. I have my fingers crossed. Thanks for your help, Raj Greg wrote: > Raj, > > You have to read the manual when doing this....Please note this BOLD FACED > caution on page 47. > > Before attempting reference calibration, > allow the transceiver to warm up at room > temperature for about 15 minutes (cover on). > > Greg > > > > > -----Original Message----- > From: Rajiv Dewan, N2RD [mailto:[EMAIL PROTECTED] > Sent: Monday, December 31, 2007 7:38 PM > To: Greg; [EMAIL PROTECTED] > Cc: Elecraft List > Subject: REF OSC Frequency > > > Great suggestion Greg. > > I did not have an appropriate cable to hook into J1 on KEF3. So I > unhooked it from KSYN3 and used the cable to J2 and some clips I had. I > have an HP5343A counter slaved to an HP3801Z GPA stabilized 10MHz > reference. Using this setup, I measured the frequency of the KREF3 > (with KTCXO option) at 30 second intervals from cold start. Here is > what I got: > > Time min:sec - Frequency 49.xxx.xxx MHz, only the KHz part is noted below: > 0:00 - 361.250 > 0:30 - 361.261 > 1:00 - 361.306 > 1:30 - 365:350 big jump!! > 2:00 - 377.346 another big jump!! > 2:30 - 377.380 > 3:00 - 377.419 > 3:30 - 377.471 > 4:00 - 377.464 > 4:30 - 377.457 > 5:00 - 377.507 > 5:30 - 377.504 > 6:00 - 377.500 > 6:30 - 377.490 > > Turned off and on right away > > 377.405 > > Is this normal? > > Thanks for the suggestion to check this. I am now going to turn it on, > wait for ten minutes, set the REF CAL and then do the VCO calibration. > > PS: I am also forwarding it to the elecraft list as the frequency drift > seems interesting. > > Raj, N2RD > > > > > > > > Greg wrote: > >> Raj. You need to do the REF CAL procedure. If you do not have an >> > accurate > >> frequency counter for method 1, use method two using USB/LSB to zero beat >> WWV. Set the radio to 10.000 MHz or 15.000 MHz. Alternate between USB >> > and > >> LSB while listening. Adjust the ref oscillator frequency so that there's >> no change in the tones. >> >> What's probably happening is the RO is off by enough that when you use the >> narrow filters you are loosing the signal as its outside the passband. >> >> Let me know how it goes. I'll be up for awhile longer. >> >> Greg >> >> >> -----Original Message----- >> From: Rajiv Dewan, N2RD [mailto:[EMAIL PROTECTED] >> Sent: Monday, December 31, 2007 6:37 PM >> To: Greg >> Subject: Re: [Elecraft] K3 #170 CW Filter oddity >> >> >> It is the default 49.380Mhz. >> >> Raj >> >> Greg wrote: >> >> >>> Raj. What freq is your reference oscillator set to? >>> >>> Greg >>> >>> >>> -----Original Message----- >>> From: [EMAIL PROTECTED] >>> [mailto:[EMAIL PROTECTED] Behalf Of Rajiv Dewan, N2RD >>> Sent: Monday, December 31, 2007 4:49 PM >>> To: [EMAIL PROTECTED]; Elecraft List >>> Subject: Re: [Elecraft] K3 #170 CW Filter oddity >>> >>> >>> Added note: the change in the DDS frequency occurs by just changing the >>> filter width or selecting the narrower filters. >>> >>> Raj >>> >>> Rajiv Dewan, N2RD wrote: >>> >>> >>> >>>> I have 250Hz, 400Hz and 2.8KHz roofing filters installed. After >>>> update to the latest firm ware I am noticing that the radio goes >>>> really deaf when the 250Hz or the 400Hz filters are used. I have set >>>> the appropriate gain of 4db and 2db, respectively for the 250Hz and >>>> 400Hz filters. The FLX FRQ is 0.0 for all. But the deafness is much >>>> more profound than a few dB. >>>> >>>> I noticed that the peak in my signal is not where CWT indicates >>>> perfect tune >>>> While I am tuned to a CW signal at 7.02706KHz, I turned on CONFIG:DDS >>>> FRQ and noticed that this frequency changes from 3.581367 MHz to >>>> 3.581579 MHz and the radio goes deaf. No change in tuned frequency. >>>> I checked that the FL FREQ for these filters is 0.0. What gives? >>>> >>>> Does any of you have the same behavior? >>>> >>>> Regards, >>>> Raj, N2RD >>>> >>>> >>>> _______________________________________________ >>>> 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 >>>> >>>> >>>> >>> _______________________________________________ >>> 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 >>> >>> >>> >> > > No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.17.13/1205 - Release Date: 12/31/2007 3:32 PM No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.17.13/1205 - Release Date: 12/31/2007 3:32 PM _______________________________________________ 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
