Re: [time-nuts] PLL Digital Loop Filter

Thanks for the hints and references everyone. I'll dig in and possibly come back with some more questions. BR, James ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow

[time-nuts] PLL Digital Loop Filter

I'm trying to understand how to design and analyze the loop filters in a digital PLL. Specifically, because of digital processing delays, the phase offset measured at time t will only produce a change on the VCXO input at time t+T, where T is the sampling period of the digital loop. I've found ple

Re: [time-nuts] HP5328A + NI GPIB-ENET/1000

Thanks for the suggestions Scott(s)! It ended up being something simple. With no signal coming into the 5328A, it did not produce any output over GPIB. I would have expected a continuous readout of 0Hz. Once I applied a signal, a simple GPIB "read" request returned the measurements I needed. No ne

[time-nuts] HP5328A + NI GPIB-ENET/1000

Does anyone have experience using older HP equipment with the NI GPIB-ENET/1000 GPIB to ethernet box? Is this even possible with such an old piece of equipment? I'm very familiar with using SCPI commands over telnet but not so familiar with HPIB. So far I've installed the NI 488.2 software which h

Re: [time-nuts] Modified Allan Deviation and counter averaging

My understanding is that MVAR(m*tau0) is equivalent to filtering the phase samples x(n) by averaging m samples to produce x'(n) [x'(n)=1/m*(x(n)+x(n+1)..x(n+m-1))] and then calculating AVAR for tau=m*tau0 on the filtered sequence. Thus, MVAR already performs an averaging/ lowpass filtering operatio

Re: [time-nuts] NTP to discipline Raspberry Pi

> > Date: Fri, 26 Jul 2013 12:27:50 +0200 > From: mike cook > To: Discussion of precise time and frequency measurement > > Subject: Re: [time-nuts] NTP to discipline Raspberry Pi > Message-ID: > Content-Type: text/plain; charset=windows-1252 > > Le 25 juil

Re: [time-nuts] NTP to discipline Raspberry Pi (Hal Murray)

> > Date: Wed, 24 Jul 2013 20:46:51 -0700 > From: Hal Murray > ja...@peroulas.com said: > > Any ideas on where I can look to track down the discrepancy? > > Dig out the kernel sources. > This would be my first time looking at kernel sources. Any suggestions as to where to start? > Who but > a t

[time-nuts] NTP to discipline Raspberry Pi

I was hoping to measure the ppm error of a Raspberry Pi's crystal using an NTP client running on the Pi itself. The NTP client reports a ppm correction that I find to be consistently (measurements performed over several days) off by about 10 ppm compared to what I measure using my GPS calibrated fr

Re: [time-nuts] time-nuts Digest, Vol 104, Issue 37

> > Date: Sun, 10 Mar 2013 17:37:13 -0700 > From: gary > To: time-nuts@febo.com > Subject: Re: [time-nuts] frequency reference for portable operation > Message-ID: <513d2739.8030...@lazygranch.com> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > I haven't researched this yet, but

Re: [time-nuts] question for expert time guys

About this subject, are you concerned with multipath? The signal from two of the basestations might arrive over a line-of-sight path whereas for the third basestation the signal might bounce around before arriving... JP - To time experts/EE's. I would like to triangulat

Re: [time-nuts] FE-5680A OSMT connector / RS232

Thanks for all your suggestions! Ends up that I seem to have found yet a different version of the 5680a :) My DDS board did have an RS232 level shifter but for some reason, the RS232 TX signal was not being brought out to the 5 pin connector. Once I soldered the TX wire directly to the SP233ACT le

[time-nuts] FE-5680A OSMT connector / RS232

measure the voltage on the RS232 TX pin (#2 from the left) it's always 0v. Shouldn't it be -12v when idle? Thanks, James On Mon, Nov 26, 2012 at 11:22 PM, James Peroulas wrote: > Was wondering if anyone ever confirmed the type of RF connector found > internally in the FE-5860a?

[time-nuts] FE-5860a internal RF connector?

Was wondering if anyone ever confirmed the type of RF connector found internally in the FE-5860a? I've seen several posts calling it a Hirose U.FL, but the linked thread suggests that it might actually be an OSMT connector: http://www.vklogger.com/forum/viewtopic.php?t=10289 Or is everyone simply

Re: [time-nuts] FE-5680A no 10MHz RF output?

> Message: 3 > Date: Sat, 24 Nov 2012 11:10:02 -0600 > From: Ed Palmer > To: Discussion of precise time and frequency measurement > > Subject: Re: [time-nuts] FE-5680A no 10MHz RF output? > Message-ID: <50b0ff6a.7030...@sasktel.net> > Content-Type: text/plain; charset=windows-1252; format

[time-nuts] FE-5680A no 10MHz RF output?

I received a 'programmable' FE-5680A from nichegeek recently and I'm able to get it to lock (pin 3 goes low) and produce a PPS output (pin 6). However, it never produces a 10MHz output on pin 7. Is this unit defective, or is there something I might be doing wrong? My unit is labeled: FE-5680A UN