Re: [time-nuts] Stepping up the output of an OCXO

Have you investigated the concept of an attenuator, to use before the RF gain block? Bill Hawkins -Original Message- Stephan Sandenbergh wrote, "The easiest, of course, would be if there exists some integrated solution. I browsed through the list of RF gain blocks on the Mini-Circuits s

Re: [time-nuts] Stepping up the output of an OCXO

Hi Bill, Judging by your question - that is probably something that I should do? Considering that you'll attenuate the 5dBm signal to about 0dBm and then amplifying it back up to about 10dBm. My gut tells me that by attenuating the signal before amplifying it will raise the noise floor. (I wouldn

Re: [time-nuts] Stepping up the output of an OCXO

Stephan Sandenbergh wrote: > Hi All, > > > > Say for instance you have a 5dBm clean 10MHz sinusoid (such as that provided > by an OCXO). Now you want to run this signal to a device that will take a > minimum of 10dBm and maximum of 15dBm as input. How does one amplify the > 5dBm? > > > > The fi

Re: [time-nuts] Stepping up the output of an OCXO

Stephan Sandenbergh wrote: >> Hi All, >> >> >> >> Say for instance you have a 5dBm clean 10MHz sinusoid (such as that provided >> by an OCXO). Now you want to run this signal to a device that will take a >> minimum of 10dBm and maximum of 15dBm as input. How does one amplify the >> 5dBm? >> >>

Re: [time-nuts] Stepping up the output of an OCXO

Stephan Sandenbergh wrote: > Hi Bill, > > Judging by your question - that is probably something that I should do? > > Considering that you'll attenuate the 5dBm signal to about 0dBm and then > amplifying it back up to about 10dBm. My gut tells me that by attenuating > the signal before amplifying i

Re: [time-nuts] Stepping up the output of an OCXO

Stephan Attached GIF file is the schematic for a common base amplifier with about 12dB of gain into a 50 ohm load. The amplifier will not saturate even if the load is open circuited. Q102 temperature compensates Q103 which regulates the dc collector current of the common base transistor. Othe

Re: [time-nuts] Stepping up the output of an OCXO

PROTECTED] On > Behalf Of Dr Bruce Griffiths > Sent: 02 February 2007 05:46 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Stepping up the output of an OCXO > > Stephan > > Attached GIF file is the schematic for a common base am

Re: [time-nuts] Stepping up the output of an OCXO

Stephan Sandenbergh wrote: > Hi Bruce, > > A great many thanks for all the hints and tips you gave me. > > Yes, I have actually started working my way through Wenzel's hints & tips > pages after I posted the first message. I remembered that you pointed me > there in a previous conversation we had.

Re: [time-nuts] Stepping up the output of an OCXO

Dr Bruce Griffiths <[EMAIL PROTECTED]> wrote: > The RF amp IC's generally have inferior noise figures and reverse > isolation (20dB for RFIC, > 40dB for common base stage) than a well > designed discrete common base amplifier. In fact by stacking common base > amplifiers the reverse isolat

Re: [time-nuts] Stepping up the output of an OCXO

2. Februar 2007 20:45 > An: Discussion of precise time and frequency measurement > Betreff: Re: [time-nuts] Stepping up the output of an OCXO > > > Dr Bruce Griffiths <[EMAIL PROTECTED]> wrote: > > The RF amp IC's generally have inferior noise figures an

Re: [time-nuts] Stepping up the output of an OCXO

Didier Juges wrote: > Dr Bruce Griffiths <[EMAIL PROTECTED]> wrote: > >> The RF amp IC's generally have inferior noise figures and reverse >> isolation (20dB for RFIC, > 40dB for common base stage) than a well >> designed discrete common base amplifier. In fact by stacking common base >

Re: [time-nuts] Stepping up the output of an OCXO

Dr Bruce Griffiths wrote: > Didier Juges wrote: > >> Bruce, >> >> In cases where the output signal does not need to be a sinewave, how would a >> common base amplifier compare to a fast comparator and if necessary a >> digital buffer as necessary to deliver the necessary power level? If this i

Re: [time-nuts] Stepping up the output of an OCXO

Ulrich Bangert wrote: > Bruce and Didier, > > i had the opportunity to measure the output to output as well as the > output to input isolation of a diy MAX477 based distribution amplifier > very similar to the TADD-1 (but not identical). The output to output > isolation was in the order of 75 dB wh

Re: [time-nuts] Stepping up the output of an OCXO

n of precise time and frequency measurement" Sent: Saturday, February 03, 2007 12:29 PM Subject: Re: [time-nuts] Stepping up the output of an OCXO > Ulrich Bangert wrote: >> Bruce and Didier, >> >> i had the opportunity to measure the output to output as well as the >

Re: [time-nuts] Stepping up the output of an OCXO

Don Don Collie wrote: > Why not use an optocoupler as an isolation amplifier? - to the best of my > knowledge it would provide infinite isolation. > Cheers,...Don Collie > > > And lots of noise. You will need a cleanup PLL on the output side. Also optocoupler

Re: [time-nuts] Stepping up the output of an OCXO

t; <[EMAIL PROTECTED]> To: "Don Collie" <[EMAIL PROTECTED]>; "Discussion of precise time and frequency measurement" Sent: Saturday, February 03, 2007 6:43 PM Subject: Re: [time-nuts] Stepping up the output of an OCXO > Don > Don Collie wrote: >> Why

Re: [time-nuts] Stepping up the output of an OCXO

t; <[EMAIL PROTECTED]> To: "Don Collie" <[EMAIL PROTECTED]>; "Discussion of precise time and frequency measurement" Sent: Saturday, February 03, 2007 6:43 PM Subject: Re: [time-nuts] Stepping up the output of an OCXO > Don > Don Collie wrote: >> Why not

Re: [time-nuts] Stepping up the output of an OCXO

> of 1part in > 10^13? > > > - Original Message - > From: "Dr Bruce Griffiths" <[EMAIL PROTECTED]> > To: "Don Collie" <[EMAIL PROTECTED]>; "Discussion of precise > time and > frequency measurement" > Sent: Saturday, Februar

Re: [time-nuts] Stepping up the output of an OCXO

Ulrich, Don Ulrich Bangert wrote: > Don, > > >> What sort of SNR is necessary to prevent an uncertaincy >> of 1part in 10^13? >> > > 110dB or more for Tau = 1sec. > I see, you are a non believer! But Bruce was talking about comparing > zero crossings of signals at a few (!) Hz, which ne

Re: [time-nuts] Stepping up the output of an OCXO

Dr Bruce Griffiths said the following on 02/02/2007 06:29 PM: > Since the MAX477 has an input noise of around 5nV/rtHz at 10MHz compared > to around 1nV/rtHz for a low noise bipolar transistor, the MAX477 may be > expected to be have a phase noise floor of up to 14dB higher than that > of an op

Re: [time-nuts] Stepping up the output of an OCXO

John Ackermann N8UR wrote: > I had a chance to measure a TADD-1 using an HP-3048 phase noise system > last year. I've attached a screen shot of the results; in short it was > below -140dBc/Hz from 100 Hz on out (by the way, I'm not sure I would > trust the noise floor shown in this test; I am not

Re: [time-nuts] Stepping up the output of an OCXO

: Discussion of precise time and frequency measurement > Betreff: Re: [time-nuts] Stepping up the output of an OCXO > > > John Ackermann N8UR wrote: > > I had a chance to measure a TADD-1 using an HP-3048 phase > noise system > > last year. I've attached a screen

Re: [time-nuts] Stepping up the output of an OCXO

Ulrich Bangert wrote: > Bruce, > > I have seen this specs before but do you know how to find the > schematics? > > Best regards > Ulric Bangert > > Ulrich NO, I'm still looking, I presume you mean the NIST amplifier schematics and not the TADD-1 schematics at: http://www.tapr.org/~n8ur/

Re: [time-nuts] Stepping up the output of an OCXO

Ulrich Bangert wrote: Bruce, I have seen this specs before but do you know how to find the schematics? Best regards Ulric Bangert Ulrich Since the earlier NBS isolation/distribution amplifiers consisted of dc coupled cascaded common base stages (according to Magnus who had looked at som

Re: [time-nuts] Stepping up the output of an OCXO

Dr Bruce Griffiths said the following on 02/04/2007 02:32 AM: > My calculations using the component values in the circuit indicate that > the TADD-1 noise figure should be about 19dB and its corresponding phase > noise floor should be lower than -160dBc/Hz. when the input signal is > +7dBm or g

Re: [time-nuts] Stepping up the output of an OCXO

From: Dr Bruce Griffiths <[EMAIL PROTECTED]> Subject: Re: [time-nuts] Stepping up the output of an OCXO Date: Mon, 05 Feb 2007 01:22:54 +1300 Message-ID: <[EMAIL PROTECTED]> > Ulrich Bangert wrote: > > Bruce, > > > > I have seen this specs before but do you kn