Luciano Paramithiotti's January 1 post about his 10-to-100 MHz multiplier project reminded me of past musings about using two 10GHz, phase-locked oscillators to compare the 10MHz outputs of my T-bolt and LPRO so I could quickly adjust the latter by observing the mixed 10 GHz signals with a microammeter. I am talking about the California Microwave, Frequency West, etc., modules that were used as local oscillators in commercial microwave systems. I was about to ask Luciano for more information on his coil forms, amplifiers, and RF chokes when it occurred to me that loop-noise in the PLOs might force a very narrow bandwidth and correspondingly long observation time. Have members of the list been successful with this technique? While most common PLO modules require an input signal in the 100 MHz-range, I have heard of versions that lock directly to a 10 MHz input. Is anyone familiar with these and how difficult it would be to modify conventional oscillators to securely lock to 10 MHz? Bruce, KG6OJI

Bruce- I can speak to the Freq West PLOs. They, like the others, use a sampling phase detector. In theory you could use any subharmonic of the actual L-band VCO frequecy to get the loop to lock. I have used freqs as low as 5MHz. But there are limitations. You must couple the signal directly to the sampler and must bypass the vhf xtal osc and amps since they are tuned for VHF. The lock-in range will be impacted since now the VCO could lock to any freq with in 5 or 10MHz of the free running VCO. I can give you more details off-list if you wish. -Brian, WA1ZMS On Jan 4, 2011, at 6:09 PM, Brucekareen@aol.com wrote: > Luciano Paramithiotti's January 1 post about his 10-to-100 MHz > multiplier > project reminded me of past musings about using two 10GHz, phase- > locked > oscillators to compare the 10MHz outputs of my T-bolt and LPRO so I > could > quickly adjust the latter by observing the mixed 10 GHz signals > with a > microammeter. I am talking about the California Microwave, > Frequency West, etc., > modules that were used as local oscillators in commercial microwave > systems. > > I was about to ask Luciano for more information on his coil forms, > amplifiers, and RF chokes when it occurred to me that loop-noise in > the PLOs might > force a very narrow bandwidth and correspondingly long observation > time. > Have members of the list been successful with this technique? > > While most common PLO modules require an input signal in the 100 > MHz-range, I have heard of versions that lock directly to a 10 MHz > input. Is anyone > familiar with these and how difficult it would be to modify > conventional > oscillators to securely lock to 10 MHz? > > Bruce, KG6OJI > _______________________________________________ > 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.

Brucekareen@aol.com wrote: > Luciano Paramithiotti's January 1 post about his 10-to-100 MHz multiplier > project reminded me of past musings about using two 10GHz, phase-locked > oscillators to compare the 10MHz outputs of my T-bolt and LPRO so I could > quickly adjust the latter by observing the mixed 10 GHz signals with a > microammeter. I am talking about the California Microwave, Frequency It has been my experience that most sources have too much jitter to multiply from 10 MHz to 10 GHz and expect to compare with a phase detector, even if the two 10 MHz sources are phase locked to each other, let alone independent. Rick Karlquist N6RK

Bruce, I had the same idea as you and my friend Frank and I performed the following experiment to check whether it is possible or not: Two brick oscillators (I believe to remember in the 8 GHz region) were locked to the same source (HP8660) in the 100 MHz region which in turn was locked to my local 10 MHz reference (Z3805). The two signals were mixed down to DC with a M14A mixer. By means of a phase shifter in one of the cables we were able to change the phase between the signals and so to determine the mixer's sensivity as a phase detector. The mixer's output was sampled with a HP3457 at a one second sample rate. The voltage measurements were then re-computed into phase fluctuations and this data was fed into my PLOTTER utility to compute what must be considered the AD noise floor of this system. I have not documented the results but I remember that the noise floor indicated a clear improvement against a direct phase comparison at 10 MHz for a given TIC resolution. What you suggest will produce you a mixer output signal which (when looked at with a scope) will easily enable you to trim your LPRO within seconds. If you can lock the bricks directly to 10 MHz this is even better. I have been thinking to use this scheme as a general tool for oscillator stability measurements. Since we must consider that two odcillators may not always be THAT close to each other in terms of frequency it would be better not to mix to zero but to a beat freaquency of say some 1-100 kHz (depends of course on the brick's pull range). This would involve a offset generator for one of the signals. I have drawn a circuit but not actually built that uses a ADF4002 and a DDS block to lock a 100 MHz signal to a 10 MHz signal where the DDS will provide the possibility to offset the 100 MHz signal in small amounts. I plan to lock two low noise WENZEL 100 MHz OCXOs to the 10 MHz sources with one of them with a small offset. Then these two 100 MHz signals are compared after being multiplied by the brick oscillators (I have two bricks that translate 100 MHz to 10 GHz). Perhaps the group can comment on the feasibility of the plan. Best regards Ulrich Bangert > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces@febo.com > [mailto:time-nuts-bounces@febo.com] Im Auftrag von Brucekareen@aol.com > Gesendet: Mittwoch, 5. Januar 2011 00:09 > An: time-nuts@febo.com > Betreff: [time-nuts] Comparing 10 MHz Oscillators at 10 GHz > > > Luciano Paramithiotti's January 1 post about his 10-to-100 > MHz multiplier > project reminded me of past musings about using two 10GHz, > phase-locked > oscillators to compare the 10MHz outputs of my T-bolt and > LPRO so I could > quickly adjust the latter by observing the mixed 10 GHz > signals with a > microammeter. I am talking about the California Microwave, > Frequency West, etc., > modules that were used as local oscillators in commercial > microwave systems. > > I was about to ask Luciano for more information on his coil forms, > amplifiers, and RF chokes when it occurred to me that > loop-noise in the PLOs might > force a very narrow bandwidth and correspondingly long > observation time. > Have members of the list been successful with this technique? > > While most common PLO modules require an input signal in the 100 > MHz-range, I have heard of versions that lock directly to a > 10 MHz input. Is anyone > familiar with these and how difficult it would be to modify > conventional > oscillators to securely lock to 10 MHz? > > Bruce, KG6OJI > _______________________________________________ > 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.

Rick, I guess what you are saying applies only to the case where one tries to mix down to DC ?? 73s de Ulrich, DF6JB > -----Ursprungliche Nachricht----- > Von: time-nuts-bounces@febo.com > [mailto:time-nuts-bounces@febo.com] Im Auftrag von Rick Karlquist > Gesendet: Mittwoch, 5. Januar 2011 01:24 > An: Discussion of precise time and frequency measurement > Betreff: Re: [time-nuts] Comparing 10 MHz Oscillators at 10 GHz > > > Brucekareen@aol.com wrote: > > Luciano Paramithiotti's January 1 post about his 10-to-100 MHz > > multiplier project reminded me of past musings about using > two 10GHz, > > phase-locked oscillators to compare the 10MHz outputs of my > T-bolt and > > LPRO so I could quickly adjust the latter by observing the > mixed 10 > > GHz signals with a microammeter. I am talking about the > California > > Microwave, Frequency > > It has been my experience that most sources have too much > jitter to multiply from 10 MHz to 10 GHz and expect to > compare with a phase detector, even if the two 10 MHz sources > are phase locked to each other, let alone independent. > > Rick Karlquist N6RK > > > _______________________________________________ > 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.

Some related measurements on 10GHz at http://www.qslnet.de/member/on4iy/9912.html Of course, the objective was not really to measure 10MHz, but rather to mimic XO PN at 10GHz using a DDS for the system as a whole (whatever that means). - the 20logN is followed very well outside the PLL loop, even though transistor multiplier stages are used, they don t seems to add significant noise compared to 20logN. - > 10KHz is ref (8662A) limited. Just some ideas, Xtof On 05/01/11 09:17, Ulrich Bangert wrote: > Bruce, > > I had the same idea as you and my friend Frank and I performed the following > experiment to check whether it is possible or not: > > Two brick oscillators (I believe to remember in the 8 GHz region) were > locked to the same source (HP8660) in the 100 MHz region which in turn was > locked to my local 10 MHz reference (Z3805). The two signals were mixed down > to DC with a M14A mixer. By means of a phase shifter in one of the cables we > were able to change the phase between the signals and so to determine the > mixer's sensivity as a phase detector. The mixer's output was sampled with a > HP3457 at a one second sample rate. The voltage measurements were then > re-computed into phase fluctuations and this data was fed into my PLOTTER > utility to compute what must be considered the AD noise floor of this > system. I have not documented the results but I remember that the noise > floor indicated a clear improvement against a direct phase comparison at 10 > MHz for a given TIC resolution. > > What you suggest will produce you a mixer output signal which (when looked > at with a scope) will easily enable you to trim your LPRO within seconds. If > you can lock the bricks directly to 10 MHz this is even better. > > I have been thinking to use this scheme as a general tool for oscillator > stability measurements. Since we must consider that two odcillators may not > always be THAT close to each other in terms of frequency it would be better > not to mix to zero but to a beat freaquency of say some 1-100 kHz (depends > of course on the brick's pull range). This would involve a offset generator > for one of the signals. I have drawn a circuit but not actually built that > uses a ADF4002 and a DDS block to lock a 100 MHz signal to a 10 MHz signal > where the DDS will provide the possibility to offset the 100 MHz signal in > small amounts. I plan to lock two low noise WENZEL 100 MHz OCXOs to the 10 > MHz sources with one of them with a small offset. Then these two 100 MHz > signals are compared after being multiplied by the brick oscillators (I have > two bricks that translate 100 MHz to 10 GHz). > > Perhaps the group can comment on the feasibility of the plan. > > Best regards > Ulrich Bangert > >> -----Ursprungliche Nachricht----- >> Von: time-nuts-bounces@febo.com >> [mailto:time-nuts-bounces@febo.com] Im Auftrag von Brucekareen@aol.com >> Gesendet: Mittwoch, 5. Januar 2011 00:09 >> An: time-nuts@febo.com >> Betreff: [time-nuts] Comparing 10 MHz Oscillators at 10 GHz >> >> >> Luciano Paramithiotti's January 1 post about his 10-to-100 >> MHz multiplier >> project reminded me of past musings about using two 10GHz, >> phase-locked >> oscillators to compare the 10MHz outputs of my T-bolt and >> LPRO so I could >> quickly adjust the latter by observing the mixed 10 GHz >> signals with a >> microammeter. I am talking about the California Microwave, >> Frequency West, etc., >> modules that were used as local oscillators in commercial >> microwave systems. >> >> I was about to ask Luciano for more information on his coil forms, >> amplifiers, and RF chokes when it occurred to me that >> loop-noise in the PLOs might >> force a very narrow bandwidth and correspondingly long >> observation time. >> Have members of the list been successful with this technique? >> >> While most common PLO modules require an input signal in the 100 >> MHz-range, I have heard of versions that lock directly to a >> 10 MHz input. Is anyone >> familiar with these and how difficult it would be to modify >> conventional >> oscillators to securely lock to 10 MHz? >> >> Bruce, KG6OJI >> _______________________________________________ >> 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. Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm

As requested I have add a PCB bottom side picture. If someone want some more informations or any help please ask me directly. See: http://www.timeok.it/files/10_to_100_mhz_multiplier.pdf I remember you the Maser use a multiplier chain from 5 MHz to 1400Mhz as first LO in the internal receiver used for PLL the FX to 1.420.xxx . Thank you, Luciano Luciano P. S. Paramithiotti -----Original Message----- From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On Behalf Of Brucekareen@aol.com Sent: mercoledì 5 gennaio 2011 0.09 To: time-nuts@febo.com Subject: [time-nuts] Comparing 10 MHz Oscillators at 10 GHz Luciano Paramithiotti's January 1 post about his 10-to-100 MHz multiplier project reminded me of past musings about using two 10GHz, phase-locked oscillators to compare the 10MHz outputs of my T-bolt and LPRO so I could quickly adjust the latter by observing the mixed 10 GHz signals with a microammeter. I am talking about the California Microwave, Frequency West, etc., modules that were used as local oscillators in commercial microwave systems. I was about to ask Luciano for more information on his coil forms, amplifiers, and RF chokes when it occurred to me that loop-noise in the PLOs might force a very narrow bandwidth and correspondingly long observation time. Have members of the list been successful with this technique? While most common PLO modules require an input signal in the 100 MHz-range, I have heard of versions that lock directly to a 10 MHz input. Is anyone familiar with these and how difficult it would be to modify conventional oscillators to securely lock to 10 MHz? Bruce, KG6OJI _______________________________________________ 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.

Very helpful On Wed, Jan 5, 2011 at 11:03 AM, Paramithiotti, Luciano Paolo S < luciano.paramithiotti@hp.com> wrote: > As requested I have add a PCB bottom side picture. > If someone want some more informations or any help please ask me directly. > See: > http://www.timeok.it/files/10_to_100_mhz_multiplier.pdf > > I remember you the Maser use a multiplier chain from 5 MHz to 1400Mhz as > first LO in the internal receiver used for PLL the FX to 1.420.xxx . > > Thank you, Luciano > > Luciano P. S. Paramithiotti > > > > -----Original Message----- > From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On > Behalf Of Brucekareen@aol.com > Sent: mercoledì 5 gennaio 2011 0.09 > To: time-nuts@febo.com > Subject: [time-nuts] Comparing 10 MHz Oscillators at 10 GHz > > Luciano Paramithiotti's January 1 post about his 10-to-100 MHz multiplier > project reminded me of past musings about using two 10GHz, phase-locked > oscillators to compare the 10MHz outputs of my T-bolt and LPRO so I could > quickly adjust the latter by observing the mixed 10 GHz signals with a > microammeter. I am talking about the California Microwave, Frequency West, > etc., modules that were used as local oscillators in commercial microwave > systems. > > I was about to ask Luciano for more information on his coil forms, > amplifiers, and RF chokes when it occurred to me that loop-noise in the PLOs > might force a very narrow bandwidth and correspondingly long observation > time. > Have members of the list been successful with this technique? > > While most common PLO modules require an input signal in the 100 > MHz-range, I have heard of versions that lock directly to a 10 MHz input. > Is anyone > familiar with these and how difficult it would be to modify conventional > oscillators to securely lock to 10 MHz? > > Bruce, KG6OJI > _______________________________________________ > 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. >