Hi Bob, It's rather curious.  Using my handheld DVM in the diode scale, I get a reading of 448 in one direction and 458 in the other with it off and cold.  In the 2K ohms scale, I get 561 and 562 ohms.  Later on, I'll pop the top off again and take a pic so I can expand it and look at it.  For what it's worth, my DDS board is 2 revisions earlier than the one Matthias Bopp modifies here "http://www.dd1us.de/Downloads/precise%20reference%20frequency%20rev%201_0.pdf" Bob >________________________________ > From: Bob Camp <lists@rtty.us> >To: Discussion of precise time and frequency measurement <time-nuts@febo.com> >Sent: Saturday, September 21, 2013 3:00 PM >Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator > > >Hi > >As far as I know the lock output is a CMOS output that will drive a couple of ma. There are so many variations that yours may indeed be an open collector and good to +15 volts. > >Bob > >On Sep 21, 2013, at 10:55 AM, Bob Stewart <bob@evoria.net> wrote: > >> The instructions I got with this Rb said that you could hook an LED through a 5-10K resistor to the +15 supply and get a lock indication.  I'm using a 10K resistor and the LED lights as soon as it's powered up from cold.  Is the loop lock indicator circuit broken or is it just another strange option for these things?  I saw on one site that if you do it this way it prevents lock, but mine seems to lock OK with or without the voltage. >> >> >> Bob - AE6RV >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > >_______________________________________________ >time-nuts mailing list -- time-nuts@febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. > > >

Hi Those readings sound a lot more like a CMOS gate output than some sort of open drain / open collector discrete driver. Bob On Sep 21, 2013, at 4:43 PM, Bob Stewart <bob@evoria.net> wrote: > Hi Bob, > > It's rather curious. Using my handheld DVM in the diode scale, I get a reading of 448 in one direction and 458 in the other with it off and cold. In the 2K ohms scale, I get 561 and 562 ohms. Later on, I'll pop the top off again and take a pic so I can expand it and look at it. For what it's worth, my DDS board is 2 revisions earlier than the one Matthias Bopp modifies here "http://www.dd1us.de/Downloads/precise%20reference%20frequency%20rev%201_0.pdf" > > Bob > > > > > >> ________________________________ >> From: Bob Camp <lists@rtty.us> >> To: Discussion of precise time and frequency measurement <time-nuts@febo.com> >> Sent: Saturday, September 21, 2013 3:00 PM >> Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator >> >> >> Hi >> >> As far as I know the lock output is a CMOS output that will drive a couple of ma. There are so many variations that yours may indeed be an open collector and good to +15 volts. >> >> Bob >> >> On Sep 21, 2013, at 10:55 AM, Bob Stewart <bob@evoria.net> wrote: >> >>> The instructions I got with this Rb said that you could hook an LED through a 5-10K resistor to the +15 supply and get a lock indication. I'm using a 10K resistor and the LED lights as soon as it's powered up from cold. Is the loop lock indicator circuit broken or is it just another strange option for these things? I saw on one site that if you do it this way it prevents lock, but mine seems to lock OK with or without the voltage. >>> >>> >>> Bob - AE6RV >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts@febo.com >>> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> >> > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there.

Hi Bob, I hooked the big voltmeter up to it, and it shows +4.2V out for about a minute, and then goes to 0.  Looking on the web, it seems like I can use that to drive a 2N2222 and put the LED and dropping resistor in the collector path with the emitter to ground?  Does that sound right? Bob >________________________________ > From: Bob Camp <lists@rtty.us> >To: Discussion of precise time and frequency measurement <time-nuts@febo.com> >Sent: Saturday, September 21, 2013 4:12 PM >Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator > > >Hi > >Those readings sound a lot more like a CMOS gate output than some sort of open drain / open collector discrete driver. > >Bob > > >On Sep 21, 2013, at 4:43 PM, Bob Stewart <bob@evoria.net> wrote: > >> Hi Bob, >> >> It's rather curious.  Using my handheld DVM in the diode scale, I get a reading of 448 in one direction and 458 in the other with it off and cold.  In the 2K ohms scale, I get 561 and 562 ohms.  Later on, I'll pop the top off again and take a pic so I can expand it and look at it.  For what it's worth, my DDS board is 2 revisions earlier than the one Matthias Bopp modifies here "http://www.dd1us.de/Downloads/precise%20reference%20frequency%20rev%201_0.pdf" >> >> Bob >> >> >> >> >> >>> ________________________________ >>> From: Bob Camp <lists@rtty.us> >>> To: Discussion of precise time and frequency measurement <time-nuts@febo.com> >>> Sent: Saturday, September 21, 2013 3:00 PM >>> Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator >>> >>> >>> Hi >>> >>> As far as I know the lock output is a CMOS output that will drive a couple of ma. There are so many variations that yours may indeed be an open collector and good to +15 volts. >>> >>> Bob >>> >>> On Sep 21, 2013, at 10:55 AM, Bob Stewart <bob@evoria.net> wrote: >>> >>>> The instructions I got with this Rb said that you could hook an LED through a 5-10K resistor to the +15 supply and get a lock indication.  I'm using a 10K resistor and the LED lights as soon as it's powered up from cold.  Is the loop lock indicator circuit broken or is it just another strange option for these things?  I saw on one site that if you do it this way it prevents lock, but mine seems to lock OK with or without the voltage. >>>> >>>> >>>> Bob - AE6RV >>>> _______________________________________________ >>>> time-nuts mailing list -- time-nuts@febo.com >>>> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>>> and follow the instructions there. >>> >>> _______________________________________________ >>> time-nuts mailing list -- time-nuts@febo.com >>> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >>> >>> >> _______________________________________________ >> time-nuts mailing list -- time-nuts@febo.com >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > >_______________________________________________ >time-nuts mailing list -- time-nuts@febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. > > >