That seems the most reasonable thing to do. Pete On 10/28/2016 3:20 PM, Tom Miller wrote: > It looks like that is the only device that could be damaged by 12 > volts. Can you find a replacement and try running at 5 volts? > > > ----- Original Message ----- From: "Peter Reilley" > <preilley_454@comcast.net> > To: "Discussion of precise time and frequency measurement" > <time-nuts@febo.com> > Sent: Friday, October 28, 2016 3:10 PM > Subject: Re: [time-nuts] Opening an Isotemp OCXO > > >> The reason that there was 12 volts on the unit was because I put it >> there. I should >> have tried 5 volts first but the only datasheet that I could find >> said 12 volts. >> All the eBay units that look the same say 12 volts. >> >> Pete. >> >> On 10/28/2016 12:53 PM, paul swed wrote: >>> I confirmed the pin out matches a 74s30 also. An S30 is TTL. Great >>> pix to >>> look at. >>> So 12 V on a 5 V chip is indeed a smoker. Find out why there was 12 V. >>> OK crazy talk I see a 1K resistor next to the VCC chip. Would anyone be >>> crazy enough to use a dropping resistor from 12 V to get 5?? Really bad >>> engineering and I don't actually believe they would. But if true a open >>> 74s30 would indeed show 12 V on pin 14. >>> Good luck. >>> Paul >>> WB8TSL >>> >>> On Fri, Oct 28, 2016 at 12:48 PM, jimlux <jimlux@earthlink.net> wrote: >>> >>>> On 10/28/16 9:13 AM, Scott Stobbe wrote: >>>> >>>>> The OCXO82-59 datasheet lists 12V supply, 5V clock out, could also >>>>> be a >>>>> blown regulator in your ocxo, if it is indeed a 12v model. >>>>> >>>>> There you go..the design could use a 74S30 as a driver - it's fast, >>>> fairly good drive, but runs off 5V. If the regulator is shorted, >>>> and you >>>> put 12V on it, it will cook. >>>> >>>> >>>> _______________________________________________ >>>> time-nuts mailing list -- time-nuts@febo.com >>>> To unsubscribe, go to https://www.febo.com/cgi-bin/m >>>> ailman/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. > >

Man O man I am loosing track here. The s30 makes it a ttl part. So 12 V would have smoked it. Seems like an easy fix for that piece at least. Regards Paul WB8TSL On Fri, Oct 28, 2016 at 3:28 PM, Peter Reilley <preilley_454@comcast.net> wrote: > That seems the most reasonable thing to do. > > Pete > > > On 10/28/2016 3:20 PM, Tom Miller wrote: > >> It looks like that is the only device that could be damaged by 12 volts. >> Can you find a replacement and try running at 5 volts? >> >> >> ----- Original Message ----- From: "Peter Reilley" < >> preilley_454@comcast.net> >> To: "Discussion of precise time and frequency measurement" < >> time-nuts@febo.com> >> Sent: Friday, October 28, 2016 3:10 PM >> Subject: Re: [time-nuts] Opening an Isotemp OCXO >> >> >> The reason that there was 12 volts on the unit was because I put it >>> there. I should >>> have tried 5 volts first but the only datasheet that I could find said >>> 12 volts. >>> All the eBay units that look the same say 12 volts. >>> >>> Pete. >>> >>> On 10/28/2016 12:53 PM, paul swed wrote: >>> >>>> I confirmed the pin out matches a 74s30 also. An S30 is TTL. Great pix >>>> to >>>> look at. >>>> So 12 V on a 5 V chip is indeed a smoker. Find out why there was 12 V. >>>> OK crazy talk I see a 1K resistor next to the VCC chip. Would anyone be >>>> crazy enough to use a dropping resistor from 12 V to get 5?? Really bad >>>> engineering and I don't actually believe they would. But if true a open >>>> 74s30 would indeed show 12 V on pin 14. >>>> Good luck. >>>> Paul >>>> WB8TSL >>>> >>>> On Fri, Oct 28, 2016 at 12:48 PM, jimlux <jimlux@earthlink.net> wrote: >>>> >>>> On 10/28/16 9:13 AM, Scott Stobbe wrote: >>>>> >>>>> The OCXO82-59 datasheet lists 12V supply, 5V clock out, could also be a >>>>>> blown regulator in your ocxo, if it is indeed a 12v model. >>>>>> >>>>>> There you go..the design could use a 74S30 as a driver - it's fast, >>>>>> >>>>> fairly good drive, but runs off 5V. If the regulator is shorted, and >>>>> you >>>>> put 12V on it, it will cook. >>>>> >>>>> >>>>> _______________________________________________ >>>>> time-nuts mailing list -- time-nuts@febo.com >>>>> To unsubscribe, go to https://www.febo.com/cgi-bin/m >>>>> ailman/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/m >>>> ailman/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/m >>> ailman/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/m > ailman/listinfo/time-nuts > and follow the instructions there. >

Can you see the voltage on the yellow dipped tantalum under the board? I think that is what it is. ----- Original Message ----- From: "Peter Reilley" <preilley_454@comcast.net> To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Sent: Friday, October 28, 2016 3:28 PM Subject: Re: [time-nuts] Opening an Isotemp OCXO > That seems the most reasonable thing to do. > > Pete > > > On 10/28/2016 3:20 PM, Tom Miller wrote: >> It looks like that is the only device that could be damaged by 12 volts. >> Can you find a replacement and try running at 5 volts? >> >> >> ----- Original Message ----- From: "Peter Reilley" >> <preilley_454@comcast.net> >> To: "Discussion of precise time and frequency measurement" >> <time-nuts@febo.com> >> Sent: Friday, October 28, 2016 3:10 PM >> Subject: Re: [time-nuts] Opening an Isotemp OCXO >> >> >>> The reason that there was 12 volts on the unit was because I put it >>> there. I should >>> have tried 5 volts first but the only datasheet that I could find said >>> 12 volts. >>> All the eBay units that look the same say 12 volts. >>> >>> Pete. >>> >>> On 10/28/2016 12:53 PM, paul swed wrote: >>>> I confirmed the pin out matches a 74s30 also. An S30 is TTL. Great pix >>>> to >>>> look at. >>>> So 12 V on a 5 V chip is indeed a smoker. Find out why there was 12 V. >>>> OK crazy talk I see a 1K resistor next to the VCC chip. Would anyone be >>>> crazy enough to use a dropping resistor from 12 V to get 5?? Really bad >>>> engineering and I don't actually believe they would. But if true a open >>>> 74s30 would indeed show 12 V on pin 14. >>>> Good luck. >>>> Paul >>>> WB8TSL >>>> >>>> On Fri, Oct 28, 2016 at 12:48 PM, jimlux <jimlux@earthlink.net> wrote: >>>> >>>>> On 10/28/16 9:13 AM, Scott Stobbe wrote: >>>>> >>>>>> The OCXO82-59 datasheet lists 12V supply, 5V clock out, could also be >>>>>> a >>>>>> blown regulator in your ocxo, if it is indeed a 12v model. >>>>>> >>>>>> There you go..the design could use a 74S30 as a driver - it's fast, >>>>> fairly good drive, but runs off 5V. If the regulator is shorted, and >>>>> you >>>>> put 12V on it, it will cook. >>>>> >>>>> >>>>> _______________________________________________ >>>>> time-nuts mailing list -- time-nuts@febo.com >>>>> To unsubscribe, go to https://www.febo.com/cgi-bin/m >>>>> ailman/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.

I have emailed Peter separately earlier today. The top side marking of the chip appears to indicate it is a TI 74LS05D. The datasheet is here: http://www.ti.com/lit/ds/symlink/sn74ls05.pdf If it is indeed a 'HEX Inverter', perhaps another 'channel' can be wired in place to see if it would work without having to find another chip. Also, I, too, was wondering if it was 5 V or if there was a 5 V regulator on the board somewhere. Hope this helps. Joe -----Original Message----- From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Tom Miller Sent: Friday, October 28, 2016 4:18 PM To: peter@reilley.com; Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Opening an Isotemp OCXO Can you see the voltage on the yellow dipped tantalum under the board? I think that is what it is. ----- Original Message ----- From: "Peter Reilley" <preilley_454@comcast.net> To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Sent: Friday, October 28, 2016 3:28 PM Subject: Re: [time-nuts] Opening an Isotemp OCXO > That seems the most reasonable thing to do. > > Pete > > > On 10/28/2016 3:20 PM, Tom Miller wrote: >> It looks like that is the only device that could be damaged by 12 volts. >> Can you find a replacement and try running at 5 volts? >> >> >> ----- Original Message ----- From: "Peter Reilley" >> <preilley_454@comcast.net> >> To: "Discussion of precise time and frequency measurement" >> <time-nuts@febo.com> >> Sent: Friday, October 28, 2016 3:10 PM >> Subject: Re: [time-nuts] Opening an Isotemp OCXO >> >> >>> The reason that there was 12 volts on the unit was because I put it >>> there. I should >>> have tried 5 volts first but the only datasheet that I could find said >>> 12 volts. >>> All the eBay units that look the same say 12 volts. >>> >>> Pete. >>> >>> On 10/28/2016 12:53 PM, paul swed wrote: >>>> I confirmed the pin out matches a 74s30 also. An S30 is TTL. Great pix >>>> to >>>> look at. >>>> So 12 V on a 5 V chip is indeed a smoker. Find out why there was 12 V. >>>> OK crazy talk I see a 1K resistor next to the VCC chip. Would anyone be >>>> crazy enough to use a dropping resistor from 12 V to get 5?? Really bad >>>> engineering and I don't actually believe they would. But if true a open >>>> 74s30 would indeed show 12 V on pin 14. >>>> Good luck. >>>> Paul >>>> WB8TSL >>>> >>>> On Fri, Oct 28, 2016 at 12:48 PM, jimlux <jimlux@earthlink.net> wrote: >>>> >>>>> On 10/28/16 9:13 AM, Scott Stobbe wrote: >>>>> >>>>>> The OCXO82-59 datasheet lists 12V supply, 5V clock out, could also be >>>>>> a >>>>>> blown regulator in your ocxo, if it is indeed a 12v model. >>>>>> >>>>>> There you go..the design could use a 74S30 as a driver - it's fast, >>>>> fairly good drive, but runs off 5V. If the regulator is shorted, and >>>>> you >>>>> put 12V on it, it will cook. >>>>> >>>>> >>>>> _______________________________________________ >>>>> time-nuts mailing list -- time-nuts@febo.com >>>>> To unsubscribe, go to https://www.febo.com/cgi-bin/m >>>>> ailman/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.

Sorry. 74S05D. Joe -----Original Message----- From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of J. L. Trantham Sent: Friday, October 28, 2016 5:50 PM To: 'Tom Miller'; 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] Opening an Isotemp OCXO I have emailed Peter separately earlier today. The top side marking of the chip appears to indicate it is a TI 74LS05D. The datasheet is here: http://www.ti.com/lit/ds/symlink/sn74ls05.pdf If it is indeed a 'HEX Inverter', perhaps another 'channel' can be wired in place to see if it would work without having to find another chip. Also, I, too, was wondering if it was 5 V or if there was a 5 V regulator on the board somewhere. Hope this helps. Joe -----Original Message----- From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Tom Miller Sent: Friday, October 28, 2016 4:18 PM To: peter@reilley.com; Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Opening an Isotemp OCXO Can you see the voltage on the yellow dipped tantalum under the board? I think that is what it is. ----- Original Message ----- From: "Peter Reilley" <preilley_454@comcast.net> To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Sent: Friday, October 28, 2016 3:28 PM Subject: Re: [time-nuts] Opening an Isotemp OCXO > That seems the most reasonable thing to do. > > Pete > > > On 10/28/2016 3:20 PM, Tom Miller wrote: >> It looks like that is the only device that could be damaged by 12 volts. >> Can you find a replacement and try running at 5 volts? >> >> >> ----- Original Message ----- From: "Peter Reilley" >> <preilley_454@comcast.net> >> To: "Discussion of precise time and frequency measurement" >> <time-nuts@febo.com> >> Sent: Friday, October 28, 2016 3:10 PM >> Subject: Re: [time-nuts] Opening an Isotemp OCXO >> >> >>> The reason that there was 12 volts on the unit was because I put it >>> there. I should >>> have tried 5 volts first but the only datasheet that I could find said >>> 12 volts. >>> All the eBay units that look the same say 12 volts. >>> >>> Pete. >>> >>> On 10/28/2016 12:53 PM, paul swed wrote: >>>> I confirmed the pin out matches a 74s30 also. An S30 is TTL. Great pix >>>> to >>>> look at. >>>> So 12 V on a 5 V chip is indeed a smoker. Find out why there was 12 V. >>>> OK crazy talk I see a 1K resistor next to the VCC chip. Would anyone be >>>> crazy enough to use a dropping resistor from 12 V to get 5?? Really bad >>>> engineering and I don't actually believe they would. But if true a open >>>> 74s30 would indeed show 12 V on pin 14. >>>> Good luck. >>>> Paul >>>> WB8TSL >>>> >>>> On Fri, Oct 28, 2016 at 12:48 PM, jimlux <jimlux@earthlink.net> wrote: >>>> >>>>> On 10/28/16 9:13 AM, Scott Stobbe wrote: >>>>> >>>>>> The OCXO82-59 datasheet lists 12V supply, 5V clock out, could also be >>>>>> a >>>>>> blown regulator in your ocxo, if it is indeed a 12v model. >>>>>> >>>>>> There you go..the design could use a 74S30 as a driver - it's fast, >>>>> fairly good drive, but runs off 5V. If the regulator is shorted, and >>>>> you >>>>> put 12V on it, it will cook. >>>>> >>>>> >>>>> _______________________________________________ >>>>> time-nuts mailing list -- time-nuts@febo.com >>>>> To unsubscribe, go to https://www.febo.com/cgi-bin/m >>>>> ailman/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.

Not S05 but S30. A 74S30 is an 8 input NAND and the foot pint on the board, looking at the inputs and outputs, seems to confirm it. There is no 5 volt regulator. The power pin is connected directly to the power pin of a 74S30. Pete. On 10/28/2016 6:50 PM, J. L. Trantham wrote: > I have emailed Peter separately earlier today. > > The top side marking of the chip appears to indicate it is a TI 74LS05D. > > The datasheet is here: > > http://www.ti.com/lit/ds/symlink/sn74ls05.pdf > > If it is indeed a 'HEX Inverter', perhaps another 'channel' can be wired in place to see if it would work without having to find another chip. > > Also, I, too, was wondering if it was 5 V or if there was a 5 V regulator on the board somewhere. > > Hope this helps. > > Joe > > > > -----Original Message----- > From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Tom Miller > Sent: Friday, October 28, 2016 4:18 PM > To: peter@reilley.com; Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Opening an Isotemp OCXO > > Can you see the voltage on the yellow dipped tantalum under the board? I think that is what it is. > > > ----- Original Message ----- > From: "Peter Reilley" <preilley_454@comcast.net> > To: "Discussion of precise time and frequency measurement" > <time-nuts@febo.com> > Sent: Friday, October 28, 2016 3:28 PM > Subject: Re: [time-nuts] Opening an Isotemp OCXO > > >> That seems the most reasonable thing to do. >> >> Pete >> >> >> On 10/28/2016 3:20 PM, Tom Miller wrote: >>> It looks like that is the only device that could be damaged by 12 volts. >>> Can you find a replacement and try running at 5 volts? >>> >>> >>> ----- Original Message ----- From: "Peter Reilley" >>> <preilley_454@comcast.net> >>> To: "Discussion of precise time and frequency measurement" >>> <time-nuts@febo.com> >>> Sent: Friday, October 28, 2016 3:10 PM >>> Subject: Re: [time-nuts] Opening an Isotemp OCXO >>> >>> >>>> The reason that there was 12 volts on the unit was because I put it >>>> there. I should >>>> have tried 5 volts first but the only datasheet that I could find said >>>> 12 volts. >>>> All the eBay units that look the same say 12 volts. >>>> >>>> Pete. >>>> >>>> On 10/28/2016 12:53 PM, paul swed wrote: >>>>> I confirmed the pin out matches a 74s30 also. An S30 is TTL. Great pix >>>>> to >>>>> look at. >>>>> So 12 V on a 5 V chip is indeed a smoker. Find out why there was 12 V. >>>>> OK crazy talk I see a 1K resistor next to the VCC chip. Would anyone be >>>>> crazy enough to use a dropping resistor from 12 V to get 5?? Really bad >>>>> engineering and I don't actually believe they would. But if true a open >>>>> 74s30 would indeed show 12 V on pin 14. >>>>> Good luck. >>>>> Paul >>>>> WB8TSL >>>>> >>>>> On Fri, Oct 28, 2016 at 12:48 PM, jimlux <jimlux@earthlink.net> wrote: >>>>> >>>>>> On 10/28/16 9:13 AM, Scott Stobbe wrote: >>>>>> >>>>>>> The OCXO82-59 datasheet lists 12V supply, 5V clock out, could also be >>>>>>> a >>>>>>> blown regulator in your ocxo, if it is indeed a 12v model. >>>>>>> >>>>>>> There you go..the design could use a 74S30 as a driver - it's fast, >>>>>> fairly good drive, but runs off 5V. If the regulator is shorted, and >>>>>> you >>>>>> put 12V on it, it will cook. >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> time-nuts mailing list -- time-nuts@febo.com >>>>>> To unsubscribe, go to https://www.febo.com/cgi-bin/m >>>>>> ailman/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. >

Oh never mind. MAJOR BF!!! How I 'morphed' S30 into S05 I can't explain. I suspect it is a 74S30 but I can't prove it. Sorry. Joe -----Original Message----- From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of J. L. Trantham Sent: Friday, October 28, 2016 5:57 PM To: 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] Opening an Isotemp OCXO Sorry. 74S05D. Joe -----Original Message----- From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of J. L. Trantham Sent: Friday, October 28, 2016 5:50 PM To: 'Tom Miller'; 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] Opening an Isotemp OCXO I have emailed Peter separately earlier today. The top side marking of the chip appears to indicate it is a TI 74LS05D. The datasheet is here: http://www.ti.com/lit/ds/symlink/sn74ls05.pdf If it is indeed a 'HEX Inverter', perhaps another 'channel' can be wired in place to see if it would work without having to find another chip. Also, I, too, was wondering if it was 5 V or if there was a 5 V regulator on the board somewhere. Hope this helps. Joe -----Original Message----- From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Tom Miller Sent: Friday, October 28, 2016 4:18 PM To: peter@reilley.com; Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Opening an Isotemp OCXO Can you see the voltage on the yellow dipped tantalum under the board? I think that is what it is. ----- Original Message ----- From: "Peter Reilley" <preilley_454@comcast.net> To: "Discussion of precise time and frequency measurement" <time-nuts@febo.com> Sent: Friday, October 28, 2016 3:28 PM Subject: Re: [time-nuts] Opening an Isotemp OCXO > That seems the most reasonable thing to do. > > Pete > > > On 10/28/2016 3:20 PM, Tom Miller wrote: >> It looks like that is the only device that could be damaged by 12 volts. >> Can you find a replacement and try running at 5 volts? >> >> >> ----- Original Message ----- From: "Peter Reilley" >> <preilley_454@comcast.net> >> To: "Discussion of precise time and frequency measurement" >> <time-nuts@febo.com> >> Sent: Friday, October 28, 2016 3:10 PM >> Subject: Re: [time-nuts] Opening an Isotemp OCXO >> >> >>> The reason that there was 12 volts on the unit was because I put it >>> there. I should >>> have tried 5 volts first but the only datasheet that I could find said >>> 12 volts. >>> All the eBay units that look the same say 12 volts. >>> >>> Pete. >>> >>> On 10/28/2016 12:53 PM, paul swed wrote: >>>> I confirmed the pin out matches a 74s30 also. An S30 is TTL. Great pix >>>> to >>>> look at. >>>> So 12 V on a 5 V chip is indeed a smoker. Find out why there was 12 V. >>>> OK crazy talk I see a 1K resistor next to the VCC chip. Would anyone be >>>> crazy enough to use a dropping resistor from 12 V to get 5?? Really bad >>>> engineering and I don't actually believe they would. But if true a open >>>> 74s30 would indeed show 12 V on pin 14. >>>> Good luck. >>>> Paul >>>> WB8TSL >>>> >>>> On Fri, Oct 28, 2016 at 12:48 PM, jimlux <jimlux@earthlink.net> wrote: >>>> >>>>> On 10/28/16 9:13 AM, Scott Stobbe wrote: >>>>> >>>>>> The OCXO82-59 datasheet lists 12V supply, 5V clock out, could also be >>>>>> a >>>>>> blown regulator in your ocxo, if it is indeed a 12v model. >>>>>> >>>>>> There you go..the design could use a 74S30 as a driver - it's fast, >>>>> fairly good drive, but runs off 5V. If the regulator is shorted, and >>>>> you >>>>> put 12V on it, it will cook. >>>>> >>>>> >>>>> _______________________________________________ >>>>> time-nuts mailing list -- time-nuts@febo.com >>>>> To unsubscribe, go to https://www.febo.com/cgi-bin/m >>>>> ailman/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.