Re: [time-nuts] 1 PPS visual Test
I'll try that out, and let you know how it goes! -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of David McGaw Sent: Monday, June 25, 2007 11:32 To: [EMAIL PROTECTED]; Discussion of precise time and frequency measurement Subject: Re: [time-nuts] 1 PPS visual Test Using "Normal" triggering, any digital scope will allow you to see the 1PPS edges clearly. Most analog scopes should have enough brightness at reasonably high sweep rate to see the edges in a darkened room or using a hood. Turn the brightness up to just below the point where a steady dot is seen on the screen with no trigger. David At 01:02 PM 6/25/2007, you wrote: >Randy, >and that's what I'm looking for, the actual measurement isn't that >important, the fidelity of the pulse is. The concern is, that if I over >drive the out put amplifiers of the distribution amps, I can make a >VERY ugly picture, much like taking a five MHz sine wave, and turning >it into a "dirty" semi square wave generator. > >Raimond > >-Original Message- >From: Randy Warner [mailto:[EMAIL PROTECTED] >Sent: Monday, June 25, 2007 10:57 >To: [EMAIL PROTECTED]; 'Discussion of precise time and >frequency measurement' >Subject: RE: [time-nuts] 1 PPS visual Test > >Raimond, > >About the only thing you can do is put the scope in normal trigger >mode, looking for a positive going transition. If you set the >horizontal sweep at about 1mS/cm you should see the rising edge of the >pulse once per second. If you have an old scope without any storage >capability the image will naturally fade quickly. This may take some >tweaking on the trigger settings for the scope, but you should be able >to find a combination of trigger settings and horizontal division size that will work. > >If your scope's trigger circuitry is stable enough you should be able >to decrease the horizontal division size so that you can get a general >idea of what the leading edge of the 1PPS pulse looks like. Depending >on the receiver it should have a very fast rise-time and be a smooth ramp. > >Naturally, you will not be able to make any measurements as to the >accuracy of the pulse, but this will give you a quick health check. > >Best regards, > >Randy Warner >Senior Applications Engineer >Geodetics, Inc. >858.729.0872 > >-Original Message- >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On >Behalf Of Raimond Melkers >Sent: Monday, June 25, 2007 8:43 AM >To: 'Discussion of precise time and frequency measurement' >Subject: [time-nuts] 1 PPS visual > > Any suggestions on the simplest, semi inexpensive way, to be able to >look at a one Pulse Per Second wave form? It's seems that most >oscilloscopes will not let me look that low in frequency. Basically I >want to know, and see if I have a pure, clean 1 PPS waveform. > >thanks, >Raimond > > > >___ >time-nuts mailing list >time-nuts@febo.com >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > > >___ >time-nuts mailing list >time-nuts@febo.com >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] 1 PPS visual Test
Randy, and that's what I'm looking for, the actual measurement isn't that important, the fidelity of the pulse is. The concern is, that if I over drive the out put amplifiers of the distribution amps, I can make a VERY ugly picture, much like taking a five MHz sine wave, and turning it into a "dirty" semi square wave generator. Raimond -Original Message- From: Randy Warner [mailto:[EMAIL PROTECTED] Sent: Monday, June 25, 2007 10:57 To: [EMAIL PROTECTED]; 'Discussion of precise time and frequency measurement' Subject: RE: [time-nuts] 1 PPS visual Test Raimond, About the only thing you can do is put the scope in normal trigger mode, looking for a positive going transition. If you set the horizontal sweep at about 1mS/cm you should see the rising edge of the pulse once per second. If you have an old scope without any storage capability the image will naturally fade quickly. This may take some tweaking on the trigger settings for the scope, but you should be able to find a combination of trigger settings and horizontal division size that will work. If your scope's trigger circuitry is stable enough you should be able to decrease the horizontal division size so that you can get a general idea of what the leading edge of the 1PPS pulse looks like. Depending on the receiver it should have a very fast rise-time and be a smooth ramp. Naturally, you will not be able to make any measurements as to the accuracy of the pulse, but this will give you a quick health check. Best regards, Randy Warner Senior Applications Engineer Geodetics, Inc. 858.729.0872 -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Raimond Melkers Sent: Monday, June 25, 2007 8:43 AM To: 'Discussion of precise time and frequency measurement' Subject: [time-nuts] 1 PPS visual Any suggestions on the simplest, semi inexpensive way, to be able to look at a one Pulse Per Second wave form? It's seems that most oscilloscopes will not let me look that low in frequency. Basically I want to know, and see if I have a pure, clean 1 PPS waveform. thanks, Raimond ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] 1 PPS visual Test
Using "Normal" triggering, any digital scope will allow you to see the 1PPS edges clearly. Most analog scopes should have enough brightness at reasonably high sweep rate to see the edges in a darkened room or using a hood. Turn the brightness up to just below the point where a steady dot is seen on the screen with no trigger. David At 01:02 PM 6/25/2007, you wrote: >Randy, >and that's what I'm looking for, the actual measurement isn't that >important, the fidelity of the pulse is. The concern is, that if I over >drive the out put amplifiers of the distribution amps, I can make a VERY >ugly picture, much like taking a five MHz sine wave, and turning it into a >"dirty" semi square wave generator. > >Raimond > >-Original Message- >From: Randy Warner [mailto:[EMAIL PROTECTED] >Sent: Monday, June 25, 2007 10:57 >To: [EMAIL PROTECTED]; 'Discussion of precise time and frequency >measurement' >Subject: RE: [time-nuts] 1 PPS visual Test > >Raimond, > >About the only thing you can do is put the scope in normal trigger mode, >looking for a positive going transition. If you set the horizontal sweep at >about 1mS/cm you should see the rising edge of the pulse once per second. If >you have an old scope without any storage capability the image will >naturally fade quickly. This may take some tweaking on the trigger settings >for the scope, but you should be able to find a combination of trigger >settings and horizontal division size that will work. > >If your scope's trigger circuitry is stable enough you should be able to >decrease the horizontal division size so that you can get a general idea of >what the leading edge of the 1PPS pulse looks like. Depending on the >receiver it should have a very fast rise-time and be a smooth ramp. > >Naturally, you will not be able to make any measurements as to the accuracy >of the pulse, but this will give you a quick health check. > >Best regards, > >Randy Warner >Senior Applications Engineer >Geodetics, Inc. >858.729.0872 > >-Original Message- >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On >Behalf Of Raimond Melkers >Sent: Monday, June 25, 2007 8:43 AM >To: 'Discussion of precise time and frequency measurement' >Subject: [time-nuts] 1 PPS visual > > Any suggestions on the simplest, semi inexpensive way, to be able to look >at a one Pulse Per Second wave form? It's seems that most oscilloscopes will >not let me look that low in frequency. Basically I want to know, and see if >I have a pure, clean 1 PPS waveform. > >thanks, >Raimond > > > >___ >time-nuts mailing list >time-nuts@febo.com >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > > >___ >time-nuts mailing list >time-nuts@febo.com >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] 1 PPS visual Test
Raimond, About the only thing you can do is put the scope in normal trigger mode, looking for a positive going transition. If you set the horizontal sweep at about 1mS/cm you should see the rising edge of the pulse once per second. If you have an old scope without any storage capability the image will naturally fade quickly. This may take some tweaking on the trigger settings for the scope, but you should be able to find a combination of trigger settings and horizontal division size that will work. If your scope's trigger circuitry is stable enough you should be able to decrease the horizontal division size so that you can get a general idea of what the leading edge of the 1PPS pulse looks like. Depending on the receiver it should have a very fast rise-time and be a smooth ramp. Naturally, you will not be able to make any measurements as to the accuracy of the pulse, but this will give you a quick health check. Best regards, Randy Warner Senior Applications Engineer Geodetics, Inc. 858.729.0872 -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Raimond Melkers Sent: Monday, June 25, 2007 8:43 AM To: 'Discussion of precise time and frequency measurement' Subject: [time-nuts] 1 PPS visual Any suggestions on the simplest, semi inexpensive way, to be able to look at a one Pulse Per Second wave form? It's seems that most oscilloscopes will not let me look that low in frequency. Basically I want to know, and see if I have a pure, clean 1 PPS waveform. thanks, Raimond ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] Tboltmon query
Since this got the attention of tbolt users, I have a question... How do I enable the Time Interval Counter (HP 53132) check box. Mine is grayed out. This would enable the setup box I assume for HPIB quarries. Thanks... Don - Original Message - From: Didier Juges To: 'Discussion of precise time and frequency measurement' Sent: Saturday, June 23, 2007 11:15 PM Subject: Re: [time-nuts] Tboltmon query This appears to be the full Hint box. I looked at the .exe file with an ASCII editor and there is nothing else. (see attached) Didier KO4BB -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Dave Brown Sent: Saturday, June 23, 2007 7:41 PM To: Discussion of precise time and frequency measurement Subject: [time-nuts] Tboltmon query Can any one tell me what the full "Hint Box' text is for the message one gets when mousing over the logging on/off box? The text starts'"When green, logging is active: when yellow,data logged that seco.." but I can't see any more text as the box is not long enough. Thanks DaveB, NZ -- ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
[time-nuts] 1 PPS visual
Any suggestions on the simplest, semi inexpensive way, to be able to look at a one Pulse Per Second wave form? It's seems that most oscilloscopes will not let me look that low in frequency. Basically I want to know, and see if I have a pure, clean 1 PPS waveform. thanks, Raimond ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] ? phase comparison or other device
From: Dr Bruce Griffiths <[EMAIL PROTECTED]> Subject: Re: [time-nuts] ? phase comparison or other device Date: Mon, 25 Jun 2007 20:37:29 +1200 Message-ID: <[EMAIL PROTECTED]> > Ulrich Bangert wrote: > > Pete, > > > > > 5. Mini-circuits BLP-1.9 low pass filter. > > > > > terminating the mixer if output with an lowpass/bandpass filter and NOT > > with an diplexer is not so good an idea. Where does the rf go? > > > > Best regards > > Ulrich Bangert > > > > > Ulrich > > This depends on whether the low pass filter has a shunt capacitor at its > input or a series inductor. > With the shunt capacitor the RF is shunted to ground through this capacitor. > With a series inductor the RF sees a relatively high input impedance and > the mixer will not perform well. Depends on what you want to acheive. NIST made some experiments and found that this was indeed what increased the gain in the frequency comparisions they made. They where infact a bit supprised as this was contruary to what they beleived. It's in the NIST archive, but I could pull the document number out if given some chance to dig around. So, what is normally a good thing in RF may not necessarilly be the best strategy for frequency comparision, at least when it comes to mixers. Cheers, Magnus ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
Re: [time-nuts] ? phase comparison or other device
Ulrich Bangert wrote: > Pete, > > 5. Mini-circuits BLP-1.9 low pass filter. > > terminating the mixer if output with an lowpass/bandpass filter and NOT > with an diplexer is not so good an idea. Where does the rf go? > > Best regards > Ulrich Bangert > > Ulrich This depends on whether the low pass filter has a shunt capacitor at its input or a series inductor. With the shunt capacitor the RF is shunted to ground through this capacitor. With a series inductor the RF sees a relatively high input impedance and the mixer will not perform well. Bruce ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
