Re: [time-nuts] GPDSO is working
Historically U(S)ARTs had the data signals in positive logic, and the control ones active low - after inversion in the level translators, signals are in "mark" (-12V) condition for an "inactive" interface. The threshold being slightly positive in "modern" EIA-232 receivers, is a "fail-safe" measure to unambiguously interpret the signals as "mark" in case the line is interrupted. If the standard thresholds would be used, in case of a line failure the line receiver would "memorize" the last state. The 75154 is one of the line receivers which can be configured in both modes (even so the thresholds are not symmetrically around GND, but the hysteresis is much larger). Also the ubiquitous 1489 could have the thresholds adjusted using the response-control pin. For experimenting, an USB-serial adapter like the FTDI MM232R could be used. It has the possibility to invert the logic signals (configurable on-chip), and to adjust the logic levels 1.8-5V (5V TTL or 3.3V LVTTL with the internal regulator), to adapt it to most logic level circuits. Even a lower power load up to ~400mA (eg. GPSRx) could be powered directly (5V), or through an external (adjustable) regulator, through the USB bus (available on most computers, unlike a "real" COM interface)... On 7/14/2013 12:25 AM, Chris Albertson wrote: On Sat, Jul 13, 2013 at 6:52 AM, Chuck Harris wrote: If a TTL signal does "just work" with your RS232 receiver, you have a faulty receiver. The receiver is supposed to have a dead zone from +3V to -3V. You are 100% correct, almost all modern RS-232 receivers are faultily as you describe and will work with TTL level signals ___ 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.
Re: [time-nuts] GPDSO is working
On Sat, Jul 13, 2013 at 6:52 AM, Chuck Harris wrote: > If a TTL signal does "just work" with your RS232 receiver, you have > a faulty receiver. The receiver is supposed to have a dead zone from > +3V to -3V. > You are 100% correct, almost all modern RS-232 receivers are faultily as you describe and will work with TTL level signals -- Chris Albertson Redondo Beach, California ___ 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.
Re: [time-nuts] GPDSO is working
But a diode with two resistors is Bert kehren Sent from Samsung tabletBob Camp wrote:Hi Hooking the ~ +/- 10V output of a MAX 232 to one of it's CMOS logic inputs probably isn't a real good idea. Two resistors and a cheap transistor make a fine inverter in this case. Bob On Jul 13, 2013, at 11:29 AM, ewkeh...@aol.com wrote: > Most MAX have two sets and one could use one as an inverter if one does not > want to add an extra IC. > Bert Kehren > > > In a message dated 7/13/2013 10:09:12 A.M. Eastern Daylight Time, > als...@nc.rr.com writes: > > Guys, > > The PIC in question was knowingly programmed "upside down" with the N > option so it could talk directly to the computer without an RS232 > converter. (input side suitably protected from -voltage levels) > > This works of most PC's which in actuality use 3.3 Volt logic in their > RS232 port and input clamp highs/lows to be within the logic family > limits. > > There are two serial port choices for a PIC in the PICAXE/BS2 compilers > N and T. > > From the PICAXE manual. > > "N idles low and T idles high. When using a simple resistor interface > use N (inverted) When using a MAX232 type interface use T" > > The bottom line is depending upon what your device is putting out and > what you are talking to you may or may not need an inverter for use with > the MAX232. > > Regards, > Brian > > On 7/13/2013 03:10, Chris Albertson wrote: >> You have it 100% correct. The UT+ uses "positive" logic are the logic 1 > is >> 5-volts but the RS-232 standard uses "negative" logic. I think the > MAX232 >> does the conversion correctly EXCEPT if you read the RS-232 standards > they >> use positive logic for the control signals. >> >> >> On Fri, Jul 12, 2013 at 7:34 PM, Bob Stewart wrote: >> >>> Hi Brian, >>> >>> That's just strange. There are a whole lot of these MAX232 and MAX3232 >>> devices being sold. Hmm, I'm looking at the UT+ User's Guide, and it > lists >>> the voltage levels as follows. These would imply that an inverter is >>> necessary, right? Could it be that someone programmed your PIC upside > down >>> - i.e. using negative logic? >>> >>> TTL >>> 0 V to 0.8 V = logic 0 >>> 2.4 V to 5.0 V = logic 1 >>> RS-232 (reordered from manual to put logic 0 on top) >>> 5 V to 15 V = logic 0 >>> -5 V to -15 V = logic 1 >>> >>> Bob - AE6RV >>> >>> >>> >>> >>>> >>>> From: Brian Alsop >>>> To: Bob Stewart ; Discussion of precise time and >>> frequency measurement >>>> Sent: Friday, July 12, 2013 9:09 PM >>>> Subject: Re: [time-nuts] GPDSO is working >>>> >>>> >>>> Hi Bob, >>>> >>>> Here is my experience. I had a PIC that output RS232 at 0-5 volt >>>> levels. It actually worked with my computer directly. When I added a >>>> MAX 232 to make the levels something like -10/+10 volts. It didn't >>>> work. That's because the MAX232 inverts the polarity. Look at the > data >>>> sheet, the level converters are clearly inverters. >>>> >>>> The fix in my case was to invert the RS232 stream output by the PIC and >>>> all was fine. >>>> >>>> I'm not sure exactly what you have but a scope sorts it out quickly. >>>> >>>> 73 de Brian/K3KO >>>> >>>> >>> ___ >>> 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. >>> >> >> >> > > > > - > No virus found in this message. > Checked by AVG - www.avg.com > Version: 2012.0.2242 / Virus Database: 3204/5987 - Release Date: 07/12/13 > > ___ > 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.
Re: [time-nuts] GPDSO is working
Hi Hooking the ~ +/- 10V output of a MAX 232 to one of it's CMOS logic inputs probably isn't a real good idea. Two resistors and a cheap transistor make a fine inverter in this case. Bob On Jul 13, 2013, at 11:29 AM, ewkeh...@aol.com wrote: > Most MAX have two sets and one could use one as an inverter if one does not > want to add an extra IC. > Bert Kehren > > > In a message dated 7/13/2013 10:09:12 A.M. Eastern Daylight Time, > als...@nc.rr.com writes: > > Guys, > > The PIC in question was knowingly programmed "upside down" with the N > option so it could talk directly to the computer without an RS232 > converter. (input side suitably protected from -voltage levels) > > This works of most PC's which in actuality use 3.3 Volt logic in their > RS232 port and input clamp highs/lows to be within the logic family > limits. > > There are two serial port choices for a PIC in the PICAXE/BS2 compilers > N and T. > > From the PICAXE manual. > > "N idles low and T idles high. When using a simple resistor interface > use N (inverted) When using a MAX232 type interface use T" > > The bottom line is depending upon what your device is putting out and > what you are talking to you may or may not need an inverter for use with > the MAX232. > > Regards, > Brian > > On 7/13/2013 03:10, Chris Albertson wrote: >> You have it 100% correct. The UT+ uses "positive" logic are the logic 1 > is >> 5-volts but the RS-232 standard uses "negative" logic. I think the > MAX232 >> does the conversion correctly EXCEPT if you read the RS-232 standards > they >> use positive logic for the control signals. >> >> >> On Fri, Jul 12, 2013 at 7:34 PM, Bob Stewart wrote: >> >>> Hi Brian, >>> >>> That's just strange. There are a whole lot of these MAX232 and MAX3232 >>> devices being sold. Hmm, I'm looking at the UT+ User's Guide, and it > lists >>> the voltage levels as follows. These would imply that an inverter is >>> necessary, right? Could it be that someone programmed your PIC upside > down >>> - i.e. using negative logic? >>> >>> TTL >>> 0 V to 0.8 V = logic 0 >>> 2.4 V to 5.0 V = logic 1 >>> RS-232 (reordered from manual to put logic 0 on top) >>>5 V to 15 V = logic 0 >>> -5 V to -15 V = logic 1 >>> >>> Bob - AE6RV >>> >>> >>> >>> >>>> >>>> From: Brian Alsop >>>> To: Bob Stewart ; Discussion of precise time and >>> frequency measurement >>>> Sent: Friday, July 12, 2013 9:09 PM >>>> Subject: Re: [time-nuts] GPDSO is working >>>> >>>> >>>> Hi Bob, >>>> >>>> Here is my experience. I had a PIC that output RS232 at 0-5 volt >>>> levels. It actually worked with my computer directly. When I added a >>>> MAX 232 to make the levels something like -10/+10 volts. It didn't >>>> work. That's because the MAX232 inverts the polarity. Look at the > data >>>> sheet, the level converters are clearly inverters. >>>> >>>> The fix in my case was to invert the RS232 stream output by the PIC and >>>> all was fine. >>>> >>>> I'm not sure exactly what you have but a scope sorts it out quickly. >>>> >>>> 73 de Brian/K3KO >>>> >>>> >>> ___ >>> 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. >>> >> >> >> > > > > - > No virus found in this message. > Checked by AVG - www.avg.com > Version: 2012.0.2242 / Virus Database: 3204/5987 - Release Date: 07/12/13 > > ___ > 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.
Re: [time-nuts] GPDSO is working
Most MAX have two sets and one could use one as an inverter if one does not want to add an extra IC. Bert Kehren In a message dated 7/13/2013 10:09:12 A.M. Eastern Daylight Time, als...@nc.rr.com writes: Guys, The PIC in question was knowingly programmed "upside down" with the N option so it could talk directly to the computer without an RS232 converter. (input side suitably protected from -voltage levels) This works of most PC's which in actuality use 3.3 Volt logic in their RS232 port and input clamp highs/lows to be within the logic family limits. There are two serial port choices for a PIC in the PICAXE/BS2 compilers N and T. >From the PICAXE manual. "N idles low and T idles high. When using a simple resistor interface use N (inverted) When using a MAX232 type interface use T" The bottom line is depending upon what your device is putting out and what you are talking to you may or may not need an inverter for use with the MAX232. Regards, Brian On 7/13/2013 03:10, Chris Albertson wrote: > You have it 100% correct. The UT+ uses "positive" logic are the logic 1 is > 5-volts but the RS-232 standard uses "negative" logic. I think the MAX232 > does the conversion correctly EXCEPT if you read the RS-232 standards they > use positive logic for the control signals. > > > On Fri, Jul 12, 2013 at 7:34 PM, Bob Stewart wrote: > >> Hi Brian, >> >> That's just strange. There are a whole lot of these MAX232 and MAX3232 >> devices being sold. Hmm, I'm looking at the UT+ User's Guide, and it lists >> the voltage levels as follows. These would imply that an inverter is >> necessary, right? Could it be that someone programmed your PIC upside down >> - i.e. using negative logic? >> >> TTL >> 0 V to 0.8 V = logic 0 >> 2.4 V to 5.0 V = logic 1 >> RS-232 (reordered from manual to put logic 0 on top) >> 5 V to 15 V = logic 0 >>-5 V to -15 V = logic 1 >> >> Bob - AE6RV >> >> >> >> >>> ________ >>> From: Brian Alsop >>> To: Bob Stewart ; Discussion of precise time and >> frequency measurement >>> Sent: Friday, July 12, 2013 9:09 PM >>> Subject: Re: [time-nuts] GPDSO is working >>> >>> >>> Hi Bob, >>> >>> Here is my experience. I had a PIC that output RS232 at 0-5 volt >>> levels. It actually worked with my computer directly. When I added a >>> MAX 232 to make the levels something like -10/+10 volts. It didn't >>> work. That's because the MAX232 inverts the polarity. Look at the data >>> sheet, the level converters are clearly inverters. >>> >>> The fix in my case was to invert the RS232 stream output by the PIC and >>> all was fine. >>> >>> I'm not sure exactly what you have but a scope sorts it out quickly. >>> >>> 73 de Brian/K3KO >>> >>> >> ___ >> 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. >> > > > - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2242 / Virus Database: 3204/5987 - Release Date: 07/12/13 ___ 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.
Re: [time-nuts] GPDSO is working
Guys, The PIC in question was knowingly programmed "upside down" with the N option so it could talk directly to the computer without an RS232 converter. (input side suitably protected from -voltage levels) This works of most PC's which in actuality use 3.3 Volt logic in their RS232 port and input clamp highs/lows to be within the logic family limits. There are two serial port choices for a PIC in the PICAXE/BS2 compilers N and T. From the PICAXE manual. "N idles low and T idles high. When using a simple resistor interface use N (inverted) When using a MAX232 type interface use T" The bottom line is depending upon what your device is putting out and what you are talking to you may or may not need an inverter for use with the MAX232. Regards, Brian On 7/13/2013 03:10, Chris Albertson wrote: You have it 100% correct. The UT+ uses "positive" logic are the logic 1 is 5-volts but the RS-232 standard uses "negative" logic. I think the MAX232 does the conversion correctly EXCEPT if you read the RS-232 standards they use positive logic for the control signals. On Fri, Jul 12, 2013 at 7:34 PM, Bob Stewart wrote: Hi Brian, That's just strange. There are a whole lot of these MAX232 and MAX3232 devices being sold. Hmm, I'm looking at the UT+ User's Guide, and it lists the voltage levels as follows. These would imply that an inverter is necessary, right? Could it be that someone programmed your PIC upside down - i.e. using negative logic? TTL 0 V to 0.8 V = logic 0 2.4 V to 5.0 V = logic 1 RS-232 (reordered from manual to put logic 0 on top) 5 V to 15 V = logic 0 -5 V to -15 V = logic 1 Bob - AE6RV From: Brian Alsop To: Bob Stewart ; Discussion of precise time and frequency measurement Sent: Friday, July 12, 2013 9:09 PM Subject: Re: [time-nuts] GPDSO is working Hi Bob, Here is my experience. I had a PIC that output RS232 at 0-5 volt levels. It actually worked with my computer directly. When I added a MAX 232 to make the levels something like -10/+10 volts. It didn't work. That's because the MAX232 inverts the polarity. Look at the data sheet, the level converters are clearly inverters. The fix in my case was to invert the RS232 stream output by the PIC and all was fine. I'm not sure exactly what you have but a scope sorts it out quickly. 73 de Brian/K3KO ___ 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. - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2242 / Virus Database: 3204/5987 - Release Date: 07/12/13 ___ 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.
Re: [time-nuts] GPDSO is working
If a TTL signal does "just work" with your RS232 receiver, you have a faulty receiver. The receiver is supposed to have a dead zone from +3V to -3V. If you can get the receiver to function with 0V to +3V, it has substandard noise immunity. And then there is the little matter of what will happen to the TTL input being connected to a real RS232 driver when It sees a potential +12V to -12V input. I know that TTL level signals used to work with the original IBM-PC comports, but they were using home made receivers and drivers that did not meet the RS-232 spec. The biggest problem with the MAX232 is its receiver was designed not to the RS232 spec, but rather to work in the same way as the IBM-PC comports. It's RS side threshold is at 1.3V, and it has only 0.5V of hysteresis. It's not a bug, it's a feature? -Chuck Harris Chris Albertson wrote: Whoever programmed the PIC in question inverted the signal for some reason. There should be no need for an inverter to use the MAX232 devices, they knew what they were doing when they designed them. If you have an inverted TTL serial signal then you can connect it straight to n RS-232 port and there is a very good change it will "just work". They call it "TTL level RS-232". BUt if you want to reliable drive a long cable it is best to level convert to true RS-232. But today most "re-232" is actually using zero and five volts. ___ 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.
Re: [time-nuts] GPDSO is working
> > Whoever programmed the PIC in question inverted the signal for some > reason. There should be no need for an inverter to use the MAX232 > devices, they knew what they were doing when they designed them. If you have an inverted TTL serial signal then you can connect it straight to n RS-232 port and there is a very good change it will "just work". They call it "TTL level RS-232". BUt if you want to reliable drive a long cable it is best to level convert to true RS-232. But today most "re-232" is actually using zero and five volts. -- Chris Albertson Redondo Beach, California ___ 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.
Re: [time-nuts] GPDSO is working
It all harkens back to the old teletype machine. Teletypes used a current loop interface, and to make sure that it was immediately obvious if the interface was broken... eg. the lines were down, the teletype was designed so that when there was current, the printer was silent, and it was the lack of current that caused the asynchronous code to progress. This "negative" logic has persisted in all teletype machines... and was incorporated by Western Electric into the RS232 interface. Whoever programmed the PIC in question inverted the signal for some reason. There should be no need for an inverter to use the MAX232 devices, they knew what they were doing when they designed them. -Chuck Harris Bob Stewart wrote: Hi Brian, That's just strange. There are a whole lot of these MAX232 and MAX3232 devices being sold. Hmm, I'm looking at the UT+ User's Guide, and it lists the voltage levels as follows. These would imply that an inverter is necessary, right? Could it be that someone programmed your PIC upside down - i.e. using negative logic? TTL 0 V to 0.8 V = logic 0 2.4 V to 5.0 V = logic 1 RS-232 (reordered from manual to put logic 0 on top) 5 V to 15 V = logic 0 -5 V to -15 V = logic 1 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.
Re: [time-nuts] GPDSO is working
You have it 100% correct. The UT+ uses "positive" logic are the logic 1 is 5-volts but the RS-232 standard uses "negative" logic. I think the MAX232 does the conversion correctly EXCEPT if you read the RS-232 standards they use positive logic for the control signals. On Fri, Jul 12, 2013 at 7:34 PM, Bob Stewart wrote: > Hi Brian, > > That's just strange. There are a whole lot of these MAX232 and MAX3232 > devices being sold. Hmm, I'm looking at the UT+ User's Guide, and it lists > the voltage levels as follows. These would imply that an inverter is > necessary, right? Could it be that someone programmed your PIC upside down > - i.e. using negative logic? > > TTL > 0 V to 0.8 V = logic 0 > 2.4 V to 5.0 V = logic 1 > RS-232 (reordered from manual to put logic 0 on top) >5 V to 15 V = logic 0 > -5 V to -15 V = logic 1 > > Bob - AE6RV > > > > > > > > From: Brian Alsop > >To: Bob Stewart ; Discussion of precise time and > frequency measurement > >Sent: Friday, July 12, 2013 9:09 PM > >Subject: Re: [time-nuts] GPDSO is working > > > > > >Hi Bob, > > > >Here is my experience. I had a PIC that output RS232 at 0-5 volt > >levels. It actually worked with my computer directly. When I added a > >MAX 232 to make the levels something like -10/+10 volts. It didn't > >work. That's because the MAX232 inverts the polarity. Look at the data > >sheet, the level converters are clearly inverters. > > > >The fix in my case was to invert the RS232 stream output by the PIC and > >all was fine. > > > >I'm not sure exactly what you have but a scope sorts it out quickly. > > > >73 de Brian/K3KO > > > > > ___ > 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. > -- Chris Albertson Redondo Beach, California ___ 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.
Re: [time-nuts] GPDSO is working
Hi Brian, That's just strange. There are a whole lot of these MAX232 and MAX3232 devices being sold. Hmm, I'm looking at the UT+ User's Guide, and it lists the voltage levels as follows. These would imply that an inverter is necessary, right? Could it be that someone programmed your PIC upside down - i.e. using negative logic? TTL 0 V to 0.8 V = logic 0 2.4 V to 5.0 V = logic 1 RS-232 (reordered from manual to put logic 0 on top) 5 V to 15 V = logic 0 -5 V to -15 V = logic 1 Bob - AE6RV > > From: Brian Alsop >To: Bob Stewart ; Discussion of precise time and frequency >measurement >Sent: Friday, July 12, 2013 9:09 PM >Subject: Re: [time-nuts] GPDSO is working > > >Hi Bob, > >Here is my experience. I had a PIC that output RS232 at 0-5 volt >levels. It actually worked with my computer directly. When I added a >MAX 232 to make the levels something like -10/+10 volts. It didn't >work. That's because the MAX232 inverts the polarity. Look at the data >sheet, the level converters are clearly inverters. > >The fix in my case was to invert the RS232 stream output by the PIC and >all was fine. > >I'm not sure exactly what you have but a scope sorts it out quickly. > >73 de Brian/K3KO > > ___ 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.
Re: [time-nuts] GPDSO is working
Hi Bob, Here is my experience. I had a PIC that output RS232 at 0-5 volt levels. It actually worked with my computer directly. When I added a MAX 232 to make the levels something like -10/+10 volts. It didn't work. That's because the MAX232 inverts the polarity. Look at the data sheet, the level converters are clearly inverters. The fix in my case was to invert the RS232 stream output by the PIC and all was fine. I'm not sure exactly what you have but a scope sorts it out quickly. 73 de Brian/K3KO On 7/13/2013 01:12, Bob Stewart wrote: Hi Brian, I don't understand. Are you saying that I need to add still more parts to get an RS-232 to TTL adapter to work? Here's the circuit for what I'm currently using, and it looks like it's inverter based. I'm not using it, because it's the only one I have and I want to keep it available for other use. http://www.scienceprog.com/wp-content/uploads/2006i/RS232_ALT/interface_schematic.gif Bob - AE6RV From: Brian Alsop To: Discussion of precise time and frequency measurement Sent: Friday, July 12, 2013 7:36 PM Subject: Re: [time-nuts] GPDSO is working Max 232's invert the polarity. You have to follow with an inverting gate if the TTL stuff worked. Brian ___ 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. - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2242 / Virus Database: 3204/5986 - Release Date: 07/12/13 - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2242 / Virus Database: 3204/5986 - Release Date: 07/12/13 ___ 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.
Re: [time-nuts] GPDSO is working
Hi Brian, I don't understand. Are you saying that I need to add still more parts to get an RS-232 to TTL adapter to work? Here's the circuit for what I'm currently using, and it looks like it's inverter based. I'm not using it, because it's the only one I have and I want to keep it available for other use. http://www.scienceprog.com/wp-content/uploads/2006i/RS232_ALT/interface_schematic.gif Bob - AE6RV > > From: Brian Alsop >To: Discussion of precise time and frequency measurement >Sent: Friday, July 12, 2013 7:36 PM >Subject: Re: [time-nuts] GPDSO is working > > >Max 232's invert the polarity. You have to follow with an inverting >gate if the TTL stuff worked. > >Brian > > ___ 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.
Re: [time-nuts] GPDSO is working
Hi Chris, I ordered a similar one today, along with a 10ft Male-Male serial cable. I'm looking forward to getting the hardware finished. I put a ZIF on the VE2ZAZ board, so next I'll probably be playing with the software. Someone on the list talked about FLL vs PLL with this card, so I'll examine that for awhile. I have a few ideas I'd like to try out that probably only apply to the OCXO I'm using. Bob > > From: Chris Albertson >To: Bob Stewart ; Discussion of precise time and frequency >measurement >Sent: Friday, July 12, 2013 7:27 PM >Subject: Re: [time-nuts] GPDSO is working > > > > > > > >I have a UT+ I bought a TTL-RS232 converter on eBay the converter is built >into a DB-9 socket. It uses male header pins for conniption, the same kind >of pins as on the UT+ >Look at item # 330838910970 on eBay. It is almost exactly what I have, lots >of people sell them. It is just the max232 chip but the packaging looks >clean and easy to use. > > >But as I remember I had to use at least one inverter gate. I forgot why maybe >to drive the PPS or the LED I wanted to add. > > >I don't have a VE2ZAZ board. I was using the UT+ for NTP server. My next >project is to build a GPSDRO (GPS Disciplined Rubidium Oscillator) I could >likely count the 10MHz output for 10,000 seconds. > ___ 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.
Re: [time-nuts] GPDSO is working
Max 232's invert the polarity. You have to follow with an inverting gate if the TTL stuff worked. Brian On 7/13/2013 00:27, Chris Albertson wrote: I have a UT+ I bought a TTL-RS232 converter on eBay the converter is built into a DB-9 socket. It uses male header pins for conniption, the same kind of pins as on the UT+ Look at item # 330838910970 on eBay. It is almost exactly what I have, lots of people sell them. It is just the max232 chip but the packaging looks clean and easy to use. But as I remember I had to use at least one inverter gate. I forgot why maybe to drive the PPS or the LED I wanted to add. I don't have a VE2ZAZ board. I was using the UT+ for NTP server. My next project is to build a GPSDRO (GPS Disciplined Rubidium Oscillator) I could likely count the 10MHz output for 10,000 seconds. On Fri, Jul 12, 2013 at 10:04 AM, Bob Stewart wrote: Hi Chris, Thanks. Our setup is a bit different. My oscillator is the Trimble 34310-T and I'm using an Oncore UT+ receiver board. What are you using for your RS-232-TTL converter? I'm looking for one that will look relatively "clean" when I get it mounted on the back of this HP 37203A box.. I'm also interested in the idea of using a USB-TTL converter, but I haven't seen a decent one with the square(ish) socket, rather than the rectangular one. Bob - AE6RV From: Chris Howard To: Bob Stewart ; Discussion of precise time and frequency measurement Sent: Friday, July 12, 2013 11:32 AM Subject: Re: [time-nuts] GPDSO is working Hi Bob. My configuration is: - HP 10811-60111 10 Mhz oscillator - Trimble Resolution-T GPS card - VE2ZAZ controller board - homebrew power supplies - RS232 switchable between GPS and VE2ZAZ controller - little e-bay puck GPS antenna on the top of an 8' post outside my window. I did get the software for the Resolution-T from the Trimble site and did a site survey. My software settings for the VE2ZAZ controller board are: S: 00E1 (a few seconds more than one hour) F: 01(for this osc the fine adj is not useful) L: B1 H: 10 W: c8 N: 0A O: 01 X: 02 M: 01 I've had the thing running for about a year. It took a while to figure out a bad solder joint in my oscillator that made the DAC voltage ineffective. Since it's been running right I have had the opportunity to compare it to a cesium standard and I'm happy. There is also a mailing list for the VE2ZAZ controller where you might find more info: http://mailman.qth.net/mailman/listinfo/gps_standard Chris w0ep ___ 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. - No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2242 / Virus Database: 3204/5986 - Release Date: 07/12/13 ___ 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.
Re: [time-nuts] GPDSO is working
I have a UT+ I bought a TTL-RS232 converter on eBay the converter is built into a DB-9 socket. It uses male header pins for conniption, the same kind of pins as on the UT+ Look at item # 330838910970 on eBay. It is almost exactly what I have, lots of people sell them. It is just the max232 chip but the packaging looks clean and easy to use. But as I remember I had to use at least one inverter gate. I forgot why maybe to drive the PPS or the LED I wanted to add. I don't have a VE2ZAZ board. I was using the UT+ for NTP server. My next project is to build a GPSDRO (GPS Disciplined Rubidium Oscillator) I could likely count the 10MHz output for 10,000 seconds. On Fri, Jul 12, 2013 at 10:04 AM, Bob Stewart wrote: > Hi Chris, > > Thanks. Our setup is a bit different. My oscillator is the Trimble > 34310-T and I'm using an Oncore UT+ receiver board. What are you using for > your RS-232-TTL converter? I'm looking for one that will look relatively > "clean" when I get it mounted on the back of this HP 37203A box.. I'm also > interested in the idea of using a USB-TTL converter, but I haven't seen a > decent one with the square(ish) socket, rather than the rectangular one. > > > Bob - AE6RV > > > > > > > From: Chris Howard > >To: Bob Stewart ; Discussion of precise time and > frequency measurement > >Sent: Friday, July 12, 2013 11:32 AM > >Subject: Re: [time-nuts] GPDSO is working > > > > > > > > > >Hi Bob. > > > >My configuration is: > > > >- HP 10811-60111 10 Mhz oscillator > >- Trimble Resolution-T GPS card > >- VE2ZAZ controller board > >- homebrew power supplies > >- RS232 switchable between GPS and VE2ZAZ controller > >- little e-bay puck GPS antenna on the top of an 8' post outside my > window. > > > >I did get the software for the Resolution-T from the Trimble > >site and did a site survey. > > > >My software settings for the VE2ZAZ controller board are: > > > >S: 00E1 (a few seconds more than one hour) > >F: 01(for this osc the fine adj is not useful) > >L: B1 > >H: 10 > >W: c8 > >N: 0A > >O: 01 > >X: 02 > >M: 01 > > > >I've had the thing running for about a year. > >It took a while to figure out a bad solder joint in > >my oscillator that made the DAC voltage ineffective. > >Since it's been running right I have had the opportunity > >to compare it to a cesium standard and I'm happy. > > > >There is also a mailing list for the VE2ZAZ controller > >where you might find more info: > > > >http://mailman.qth.net/mailman/listinfo/gps_standard > > > >Chris > >w0ep > > > ___ > 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. > -- Chris Albertson Redondo Beach, California ___ 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.
Re: [time-nuts] GPDSO is working
Hi Chris, Thanks. Our setup is a bit different. My oscillator is the Trimble 34310-T and I'm using an Oncore UT+ receiver board. What are you using for your RS-232-TTL converter? I'm looking for one that will look relatively "clean" when I get it mounted on the back of this HP 37203A box.. I'm also interested in the idea of using a USB-TTL converter, but I haven't seen a decent one with the square(ish) socket, rather than the rectangular one. Bob - AE6RV > > From: Chris Howard >To: Bob Stewart ; Discussion of precise time and frequency >measurement >Sent: Friday, July 12, 2013 11:32 AM >Subject: Re: [time-nuts] GPDSO is working > > > > >Hi Bob. > >My configuration is: > > - HP 10811-60111 10 Mhz oscillator > - Trimble Resolution-T GPS card > - VE2ZAZ controller board > - homebrew power supplies > - RS232 switchable between GPS and VE2ZAZ controller > - little e-bay puck GPS antenna on the top of an 8' post outside my window. > >I did get the software for the Resolution-T from the Trimble >site and did a site survey. > >My software settings for the VE2ZAZ controller board are: > >S: 00E1 (a few seconds more than one hour) >F: 01 (for this osc the fine adj is not useful) >L: B1 >H: 10 >W: c8 >N: 0A >O: 01 >X: 02 >M: 01 > >I've had the thing running for about a year. >It took a while to figure out a bad solder joint in >my oscillator that made the DAC voltage ineffective. >Since it's been running right I have had the opportunity >to compare it to a cesium standard and I'm happy. > >There is also a mailing list for the VE2ZAZ controller >where you might find more info: > >http://mailman.qth.net/mailman/listinfo/gps_standard > >Chris >w0ep > ___ 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.
Re: [time-nuts] GPDSO is working
Hi Bob. My configuration is: - HP 10811-60111 10 Mhz oscillator - Trimble Resolution-T GPS card - VE2ZAZ controller board - homebrew power supplies - RS232 switchable between GPS and VE2ZAZ controller - little e-bay puck GPS antenna on the top of an 8' post outside my window. I did get the software for the Resolution-T from the Trimble site and did a site survey. My software settings for the VE2ZAZ controller board are: S: 00E1 (a few seconds more than one hour) F: 01(for this osc the fine adj is not useful) L: B1 H: 10 W: c8 N: 0A O: 01 X: 02 M: 01 I've had the thing running for about a year. It took a while to figure out a bad solder joint in my oscillator that made the DAC voltage ineffective. Since it's been running right I have had the opportunity to compare it to a cesium standard and I'm happy. There is also a mailing list for the VE2ZAZ controller where you might find more info: http://mailman.qth.net/mailman/listinfo/gps_standard Chris w0ep On 7/12/2013 10:32 AM, Bob Stewart wrote: > Hi Chris, > > Thanks for the feedback. Do you happen to know the parameters you have setup > for yours? Just wondering what you are using for the "F", "M", and "S" > parameters. What kind of receiver are you driving yours with, and do you > have it in "position hold" mode? > > > Bob > > > > >> >> From: Chris Howard >> To: Bob Stewart >> Sent: Friday, July 12, 2013 6:45 AM >> Subject: Re: [time-nuts] GPDSO is working >> >> >> On 7/11/2013 10:59 PM, Bob Stewart wrote: >>> After ham-fistedly breaking a few things, I've finally got my GPSDO >>> working. (does happy dance) Now that it's had some time to warm up I see >>> that it's started wandering around +/- a couple of counts from sample to >>> sample (16 seconds). Is this because the UT+ is not set to timing mode? >>> Putting in an RS-232 (or USB) to TTL adapter, switchable between the UT+ >>> and the VE2ZAZ board, is pretty much next on my schedule. I've got an >>> adapter I made many years ago, but it's not suitable for mounting in the >>> box, and there's no simple way to hook it up to the UT+ at the moment. >>> >>> Bob >> >> I think I recall you are using the VE2ZAZ board. >> >> Yes, the count each time goes up and down. >> I am using that board >> and mine goes up and down, roughly in the >> +/- 5 range. >> >> >> Chris >> w0ep >> >> >> >> >> >> >> > ___ > 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.
Re: [time-nuts] GPDSO is working
The periodic +/- might be caused by periodic error in the PPS. The UT+ has an error "sawtooth" function. That is the error is the PPS is left to accumulate and then it is reset. So if you DAC counts goes up and down on a few seconds or few tens of seconds period it could be tracking the error in the PPS.The UT+ keeps its PPS within spec. Once you gt the serial line connected you will be able to read the sawtooth corrections. The UT+ out puts the estimated error in the PPS and I guess a very sophisticated GPSDO would use that data to correct the phase measurement.From memory, I think with a UT+ the error in the PPS goes up to about 50 ns. (I have a couple UT+) -- Chris Albertson Redondo Beach, California ___ 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.
Re: [time-nuts] GPDSO is working
Hi You will need to fine tune the firmware settings for that OCXO. Bob On Jul 12, 2013, at 11:27 AM, Bob Stewart wrote: > Hi Bob, > > OK, you got me: time as in about 120 minutes. =) It's mostly "+", with the > occasional "-" for about an hour or so. Then, it wavers back and forth > between "+" and "-", but the long term trend is still very slowly "+".So, > I guess the OCXO needs more time to "settle in"? My OCXO is a Trimble > 34310-T. > > As soon as I can get the serial port wiring done I'll be able to tell if it's > in "position hold" mode. I suspect it's not, as it doesn't have a battery > on-board. I did wind up mounting a Lithium 3V backup battery, using a holder > from an old motherboard. > > I'll have to look around to see if anyone has any software to graph the DAC > track for this board. > > Bob - AE6RV > > > > > >> ________________ >> From: Bob Camp >> To: Discussion of precise time and frequency measurement >> >> Sent: Friday, July 12, 2013 8:47 AM >> Subject: Re: [time-nuts] GPDSO is working >> >> >> Hi >> >> On Jul 11, 2013, at 11:59 PM, Bob Stewart wrote: >> >>> After ham-fistedly breaking a few things, I've finally got my GPSDO >>> working. (does happy dance) Now that it's had some time to warm up >> >> Time as in minutes, or as in a couple of days? If you look at the plot in >> the QEX article, a day or so is the expected "warmup" period. >> >>> I see that it's started wandering around +/- a couple of counts from sample >>> to sample (16 seconds). >> >> If it's + *and* - then the gizmo is driving down the middle of the road. If >> it's always + or always - then it's likely not yet locked. >> >>> Is this because the UT+ is not set to timing mode? >> >> The UT needs to be in "position hold" mode with a proper (24 to 48 hour) >> survey on it's location for best performance. It should not be +/- 100 ns >> even without this. >> >> Is your VCXO a 10811? Does it have the same sensitivity as a 10811? If not, >> you may need (per the article) to make some firmware changes. >> >> Bob >> >>> Putting in an RS-232 (or USB) to TTL adapter, switchable between the UT+ >>> and the VE2ZAZ board, is pretty much next on my schedule. I've got an >>> adapter I made many years ago, but it's not suitable for mounting in the >>> box, and there's no simple way to hook it up to the UT+ at the moment. >>> >>> Bob >>> ___ >>> 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.
Re: [time-nuts] GPDSO is working
Hi Azelio I'm not tracking it with a counter. The VE2ZAZ board I mentioned in my post has a serial port interface. Every 32 seconds you get a line of tracking information, which includes the right 4 digits of the hex count of how many oscillator transitions occurred during the previous 16 second sampling period. With an oscillator of 10 MHz there will be 160,000,000 transitions during the 10 second sampling period for a dead accurate oscillator. It also gives an error count for each period so you don't have to do the math to subtract it. This error count value is the one I'm referring to. Bob - AE6RV > > From: Azelio Boriani >To: Discussion of precise time and frequency measurement >Sent: Friday, July 12, 2013 3:50 AM >Subject: Re: [time-nuts] GPDSO is working > > >No, it doesn't depend on the timing mode. What reference are you >using? That is, your counter is using its internal reference or else. > >On Fri, Jul 12, 2013 at 5:59 AM, Bob Stewart wrote: >> After ham-fistedly breaking a few things, I've finally got my GPSDO working. >> (does happy dance) Now that it's had some time to warm up I see that it's >> started wandering around +/- a couple of counts from sample to sample (16 >> seconds). Is this because the UT+ is not set to timing mode? Putting in an >> RS-232 (or USB) to TTL adapter, switchable between the UT+ and the VE2ZAZ >> board, is pretty much next on my schedule. I've got an adapter I made many >> years ago, but it's not suitable for mounting in the box, and there's no >> simple way to hook it up to the UT+ at the moment. >> >> Bob >> ___ >> 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.
Re: [time-nuts] GPDSO is working
Hi Chris, Thanks for the feedback. Do you happen to know the parameters you have setup for yours? Just wondering what you are using for the "F", "M", and "S" parameters. What kind of receiver are you driving yours with, and do you have it in "position hold" mode? Bob > > From: Chris Howard >To: Bob Stewart >Sent: Friday, July 12, 2013 6:45 AM >Subject: Re: [time-nuts] GPDSO is working > > >On 7/11/2013 10:59 PM, Bob Stewart wrote: >> After ham-fistedly breaking a few things, I've finally got my GPSDO working. >> (does happy dance) Now that it's had some time to warm up I see that it's >> started wandering around +/- a couple of counts from sample to sample (16 >> seconds). Is this because the UT+ is not set to timing mode? Putting in an >> RS-232 (or USB) to TTL adapter, switchable between the UT+ and the VE2ZAZ >> board, is pretty much next on my schedule. I've got an adapter I made many >> years ago, but it's not suitable for mounting in the box, and there's no >> simple way to hook it up to the UT+ at the moment. >> >> Bob > >I think I recall you are using the VE2ZAZ board. > >Yes, the count each time goes up and down. >I am using that board >and mine goes up and down, roughly in the >+/- 5 range. > > >Chris >w0ep > > > > > > > ___ 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.
Re: [time-nuts] GPDSO is working
Hi Bob, OK, you got me: time as in about 120 minutes. =) It's mostly "+", with the occasional "-" for about an hour or so. Then, it wavers back and forth between "+" and "-", but the long term trend is still very slowly "+". So, I guess the OCXO needs more time to "settle in"? My OCXO is a Trimble 34310-T. As soon as I can get the serial port wiring done I'll be able to tell if it's in "position hold" mode. I suspect it's not, as it doesn't have a battery on-board. I did wind up mounting a Lithium 3V backup battery, using a holder from an old motherboard. I'll have to look around to see if anyone has any software to graph the DAC track for this board. Bob - AE6RV > > From: Bob Camp >To: Discussion of precise time and frequency measurement >Sent: Friday, July 12, 2013 8:47 AM >Subject: Re: [time-nuts] GPDSO is working > > >Hi > >On Jul 11, 2013, at 11:59 PM, Bob Stewart wrote: > >> After ham-fistedly breaking a few things, I've finally got my GPSDO working. >> (does happy dance) Now that it's had some time to warm up > >Time as in minutes, or as in a couple of days? If you look at the plot in the >QEX article, a day or so is the expected "warmup" period. > >> I see that it's started wandering around +/- a couple of counts from sample >> to sample (16 seconds). > >If it's + *and* - then the gizmo is driving down the middle of the road. If >it's always + or always - then it's likely not yet locked. > >> Is this because the UT+ is not set to timing mode? > >The UT needs to be in "position hold" mode with a proper (24 to 48 hour) >survey on it's location for best performance. It should not be +/- 100 ns even >without this. > >Is your VCXO a 10811? Does it have the same sensitivity as a 10811? If not, >you may need (per the article) to make some firmware changes. > >Bob > >> Putting in an RS-232 (or USB) to TTL adapter, switchable between the UT+ and >> the VE2ZAZ board, is pretty much next on my schedule. I've got an adapter I >> made many years ago, but it's not suitable for mounting in the box, and >> there's no simple way to hook it up to the UT+ at the moment. >> >> Bob >> ___ >> 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.
Re: [time-nuts] GPDSO is working
Hi On Jul 11, 2013, at 11:59 PM, Bob Stewart wrote: > After ham-fistedly breaking a few things, I've finally got my GPSDO working. > (does happy dance) Now that it's had some time to warm up Time as in minutes, or as in a couple of days? If you look at the plot in the QEX article, a day or so is the expected "warmup" period. > I see that it's started wandering around +/- a couple of counts from sample > to sample (16 seconds). If it's + *and* - then the gizmo is driving down the middle of the road. If it's always + or always - then it's likely not yet locked. > Is this because the UT+ is not set to timing mode? The UT needs to be in "position hold" mode with a proper (24 to 48 hour) survey on it's location for best performance. It should not be +/- 100 ns even without this. Is your VCXO a 10811? Does it have the same sensitivity as a 10811? If not, you may need (per the article) to make some firmware changes. Bob > Putting in an RS-232 (or USB) to TTL adapter, switchable between the UT+ and > the VE2ZAZ board, is pretty much next on my schedule. I've got an adapter I > made many years ago, but it's not suitable for mounting in the box, and > there's no simple way to hook it up to the UT+ at the moment. > > Bob > ___ > 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.
Re: [time-nuts] GPDSO is working
No, it doesn't depend on the timing mode. What reference are you using? That is, your counter is using its internal reference or else. On Fri, Jul 12, 2013 at 5:59 AM, Bob Stewart wrote: > After ham-fistedly breaking a few things, I've finally got my GPSDO working. > (does happy dance) Now that it's had some time to warm up I see that it's > started wandering around +/- a couple of counts from sample to sample (16 > seconds). Is this because the UT+ is not set to timing mode? Putting in an > RS-232 (or USB) to TTL adapter, switchable between the UT+ and the VE2ZAZ > board, is pretty much next on my schedule. I've got an adapter I made many > years ago, but it's not suitable for mounting in the box, and there's no > simple way to hook it up to the UT+ at the moment. > > Bob > ___ > 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] GPDSO is working
After ham-fistedly breaking a few things, I've finally got my GPSDO working. (does happy dance) Now that it's had some time to warm up I see that it's started wandering around +/- a couple of counts from sample to sample (16 seconds). Is this because the UT+ is not set to timing mode? Putting in an RS-232 (or USB) to TTL adapter, switchable between the UT+ and the VE2ZAZ board, is pretty much next on my schedule. I've got an adapter I made many years ago, but it's not suitable for mounting in the box, and there's no simple way to hook it up to the UT+ at the moment. Bob ___ 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.
