Bob, I would bump that base resistor up a lot higher, to load the FE-5680 less. The PN2222 has enough gain it only needs about 0.3 mA base drive to work as intended. You'd get that with a 10K base resistor.
Bob LaJeunesse >________________________________ > From: Bob Stewart <b...@evoria.net> >To: Time Nuts <time-nuts@febo.com> >Sent: Saturday, September 21, 2013 10:02 PM >Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator > > >Hi John, > >Thanks for the response. I managed to cobble something up with LTSpiceIV, and >get it to work. And for me, that's saying something! Here's what I wound >up with: "http://www.evoria.net/AE6RV/GPSstd_PLL/LED-driver.png";, where V2 is >the Loop Lock Indicator. The PN2222 shorts out the LED until it goes into >lock, then the LED comes on. It does give a short pulse when power is first >applied and things are equalizing. Even with a 1K resistor, the 4.2V from >Lock signal is pulled down to 3V. > >And here's a pic of my Rb standard on it's temporary home with the LED on a >scrap of breadboard: >"http://www.evoria.net/AE6RV/GPSstd_PLL/Rb.standard.png";. > >Bob > > > > > >>________________________________ >> From: jmfranke <jmfra...@cox.net> >>To: Bob Stewart <b...@evoria.net>; Discussion of precise time and frequency >>measurement <time-nuts@febo.com> >>Sent: Saturday, September 21, 2013 6:58 PM >>Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator >> >> >>Yes, but put an isolation resistor between the output and the base of the >>transistor, something between 3K and 5K should work. The LED will light upon >>power on and extinguish when lock is achieved. >> >>John WA4WDL >> >> >>-------------------------------------------------- >>From: "Bob Stewart" <b...@evoria.net> >>Sent: Saturday, September 21, 2013 6:10 PM >>To: "Discussion of precise time and frequency measurement" >><time-nuts@febo.com> >>Subject: Re: [time-nuts] FE-5680A Loop Lock Indicator >> >>> 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 <li...@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 <b...@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 <li...@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 <b...@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. >>>> >>>> >>>> >>> _______________________________________________ >>> 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.
![http://www.evoria.net/AE6RV/GPSstd_PLL/LED-driver.png"](http://www.evoria.net/AE6RV/GPSstd_PLL/LED-driver.png"){kind=link}
![http://www.evoria.net/AE6RV/GPSstd_PLL/Rb.standard.png"](http://www.evoria.net/AE6RV/GPSstd_PLL/Rb.standard.png"){kind=link}