[time-nuts] Z3801A up and running!
First of all, many thanks to those who gave help, hints, ideas, and schematics (!) over the past eight months; all was appreciated! The story: I was building a master power/timing module for my rack system, including a Z3801A in a snazzy pull-out configuration with a dist. amp. All was great until I did the final power on test... The Z3801A was dead and the external PS shut itself down for ~4 minutes every time I tried to power it up. I had forgotten that the unit was designed for a *positive ground* environment... oops! After a few half hearted attempts to get it going, I gave up for a while to work on other projects. Later, knowing I had to thin out the herd I asked for and got the schematics for the PS board. While not 100% accurate, they were good enough. The incorrect grounding had blown out Q3 and CR4. I took a long time to track it down because it was hard to isolate portions of the circuit, and I didn't want to cut any traces. Deciding I didn't need the input voltage envelope circuit anyway, I just bypassed Q2, reassembled everything, and it's now purring along. Not having much luck acquiring sats, but it's locked on to a few, not bad considering the antenna is indoors, leaning against a book case. This weekend, I'll give it a real test on the roof. One last thing; this was the first pcb I've really had soldering issues with. Sometimes it just wouldn't melt unless I used the big weller gun, sometimes the clearance in the holes was so tight that I had to pull parts through even when the solder was totally melted. The pcb laughed at both my solder-suckers. I even ended up making a tip to heat all 3 terminals of a TO-220 at once. That worked, but the 2 wide tip for the DC/DC conv. didn't Thanks again to all, -Dave ___ 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] 58532a ANTENNA CABLE?
I am in the process of setting up a Z3801A and would like to know what type of cable I should use for a 50' run to an 58532A antenna. What do you have handy? How nutty are you? If you have 50 ft of something, give it a try. I'm assuming you can try it easily, for example by tossing the cable out a window rather than going through all the effort of making a neat installation. One of the GPS manufacturers suggests using RG-6 even though it's 75 ohms rather than 50. The idea is that the low(er) loss at 1.4 GHz more than compensates for the impedance mismatch. RG-6 is cable TV gear. You can get it cheap. My antenna is inside my junk room. I'm using 25 ft of LMR-???. It's right on the edge of being good enough. My Z3801A runs out of satellites occasionally (once or twice per week). Also I need to purchase one of the monitoring software programs for this Z3801A, any suggestions. What do you want to monitor? Do you like programming? The specs are readily available. With a bit of hacking you can collect whatever info you want then feed it to your favorite graphing program. I use gnuplot. -- These are my opinions, not necessarily my employer's. I hate spam. ___ 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] Buffering the 1pps output from a Z3801A
Thank you all for your replies. The sidecar is a bigger project than I had in mind, but would certainly be a better and more versatile solution. Regards, Peter Vince ___ 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] sell hp z3816a and trimble Thunderbolt GPS Disciplined Clock hp Z3817A. Remote High Stability Oscillator on ebay
i am selling lots of rubiduim oscillators and gps disciplined one ebay. if you want to buy see the item on ebay HP z3816a :ITEM NO 300210068706 trimble gps disciplined : ITEM NO 300210065008 hp Z3817A. Remote High Stability Oscillator come with HP E1938A Quartz Oscillator ITEM NO 300210127000 please bidding for what you want buy. i come from china.the all the thing i had tested and working good before i send i also have fei fe-5882a rubiduim oscillator, SRS PRS10 rubiduim oscillator ,fei fe-5680a (without J1 ) , if you want buy please contact me. ___ 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] Trimble Navigation PN 27760-10
I got my hands on a defunct Trimble Navigation unit PN 27760-10. I don't know much about the unit other than it used to work very well in the late 90s until someone decided to do a firmware upgrade on it. The newest firmware version is not compatible and now it's having some issues. It can't be reflashed, on top of that I don't have the old flash file. It would be extremely interesting to get this working. There are 4 antennas labeled M, 1, 2, 3. Antennas 1, 2, and 3 are not working, only M. Trimble said there are no parts available and they BERed (beyond economic repair) it when it was sent back to them. The packing list from Trimble lists the description is OBSO Vector TANS RPU ASSY 28V. Anyone familiar with it or if I'm really luck have an older version of the firmware I could burn. Thanks Shane ___ 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] 58532a ANTENNA CABLE?
There appears to be three software-monitoring programs available, GPSCon Pro, GPS Control SatStat. I was just curious about what the group thinks of these three programs or if there are any other available. The Z3801A manual suggest rg-213 of lmr-400. I have neither on hand but am not apposed to purchasing either. I do have rg58/u and coax CATV cable on hand but the problem is that it is a difficult process to run the cable from my basement lab to the second floor attic and I only o want to do it once. Originally, I was going to penetrate the roof at the ridgeline and install the antenna on a one foot but I understand it is possible to receive singles from under the plywood/asphalt shingle roof. Is it worth a penetration of the roof? Jeff ___ 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] 58532a ANTENNA CABLE?
Hi Jeff, I have used both SatStat and GPSCon on a Z3801A, Fury, and FireFly. Satstat has no graphical interface, and it was so old that it was really tough to get up and running on XP. But I was eventually able to get it up, and I think it's available for free. Very basic text-based interface. I can highly recommend GPSCon, it allows for graphing standard features such as EFC and TI, but also allows you to add your own customized data query commands, and graph them. It can also support more than one GPSDO. Lastly, GPSCon supports a large number of Web features, FTP login, SNTP server, Web Server, Email alarms, etc etc. The only drawbacks for GPSCon are that there are so many features to play with that sometimes it's a bit cluttered to find what you are looking for, and it can get quite slow when logging many GPSDO's over long time-frames. Hope that helps, bye, Said In a message dated 3/27/2008 11:40:48 Pacific Daylight Time, [EMAIL PROTECTED] writes: There appears to be three software-monitoring programs available, GPSCon Pro, GPS Control SatStat. I was just curious about what the group thinks of these three programs or if there are any other available. **Create a Home Theater Like the Pros. Watch the video on AOL Home. (http://home.aol.com/diy/home-improvement-eric-stromer?video=15ncid=aolhom000301) ___ 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] 58532a ANTENNA CABLE?
There appears to be three software-monitoring programs available, GPSCon Pro, GPS Control SatStat. I was just curious about what the group thinks of these three programs or if there are any other available. SatStat is free. It will get you off the ground. I do have rg58/u and coax CATV cable on hand but the problem is that it is a difficult process to run the cable from my basement lab to the second floor attic and I only o want to do it once. Originally, I was going to penetrate the roof at the ridgeline and install the antenna on a one foot but I understand it is possible to receive singles from under the plywood/asphalt shingle roof. Is it worth a penetration of the roof? I don't think you are going to get a simple answer. That's why I suggested experimenting. RG-58 is fairly high loss. I doubt if it will work at 50 ft. Cable TV coax is readily available in two flavors: RG-59 and RG-6. (Or did 10 years ago when I last looked.) The RG-6 may be advertised as low-loss. It's significantly bigger. If you have enough RG-6, I'd start by feeding it out a window or run it up the stairs and out the door. Put the antenna out in the open. If that works, it will probably work better on top of your roof. If it works well, you can try tucking the antenna up under the eaves. That's a good approximation of inside your attic below the roof. There is a slight quirk. You have to get it working before you know it's working. You probably need to do a Survey. If your antenna is marginal, you can watch it struggle to find satellites until it gets locked up. (The Status page will show you what satellites it is working on.) -- These are my opinions, not necessarily my employer's. I hate spam. ___ 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] GPS PRN07 tracking
Hi! Earlier this month the launched the latest of the GPS IIR-M sats, and today I had the oppertunity to observe it. It seems it was brought quickly on air as operational. It runs at PRN 07. Cheers, Magnus ___ 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] GPS PRN07 tracking
And they turned off PRN 10 the next day after making PRN 07 valid. It's like they're playing GPS wack-a-mole. jeff Magnus Danielson wrote: Hi! Earlier this month the launched the latest of the GPS IIR-M sats, and today I had the oppertunity to observe it. It seems it was brought quickly on air as operational. It runs at PRN 07. Cheers, Magnus ___ 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] 58532a ANTENNA CABLE?
Hi Jeff- I have only used SatStat with my Z3801A, and it did take a while to get it set up right under XP. I much prefer Tboltmon for the Thunderbolt. Now that both are functional, I can start playing with them. I found that the Z3801A with the std HP antenna and recommended cable didn't work very well with the antenna in the garage (no plywood, 1x6s and 3 layers of asphalt shingles), it took forever to acquire sats and would lose the lock at the drop of a hat. It had to go out in the weather to be stable. On the other hand, the Thunderbolt antenna is in the corner of the garage, tilted at an angle, with hanging bicycles on one side and 19 racks on another, and is happy as a clam. Are clams happy? I've always wondered about that saying... -Dave -- Original message -- From: jshank [EMAIL PROTECTED] There appears to be three software-monitoring programs available, GPSCon Pro, GPS Control SatStat. I was just curious about what the group thinks of these three programs or if there are any other available. The Z3801A manual suggest rg-213 of lmr-400. I have neither on hand but am not apposed to purchasing either. I do have rg58/u and coax CATV cable on hand but the problem is that it is a difficult process to run the cable from my basement lab to the second floor attic and I only o want to do it once. Originally, I was going to penetrate the roof at the ridgeline and install the antenna on a one foot but I understand it is possible to receive singles from under the plywood/asphalt shingle roof. Is it worth a penetration of the roof? Jeff ___ 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] 58532a ANTENNA CABLE?
I never heard a clam complain, so... ;-} Jean-Louis Oneto - Original Message - From: [EMAIL PROTECTED] To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Thursday, March 27, 2008 10:53 PM Subject: Re: [time-nuts] 58532a ANTENNA CABLE? Hi Jeff- I have only used SatStat with my Z3801A, and it did take a while to get it set up right under XP. I much prefer Tboltmon for the Thunderbolt. Now that both are functional, I can start playing with them. I found that the Z3801A with the std HP antenna and recommended cable didn't work very well with the antenna in the garage (no plywood, 1x6s and 3 layers of asphalt shingles), it took forever to acquire sats and would lose the lock at the drop of a hat. It had to go out in the weather to be stable. On the other hand, the Thunderbolt antenna is in the corner of the garage, tilted at an angle, with hanging bicycles on one side and 19 racks on another, and is happy as a clam. Are clams happy? I've always wondered about that saying... -Dave -- Original message -- From: jshank [EMAIL PROTECTED] There appears to be three software-monitoring programs available, GPSCon Pro, GPS Control SatStat. I was just curious about what the group thinks of these three programs or if there are any other available. The Z3801A manual suggest rg-213 of lmr-400. I have neither on hand but am not apposed to purchasing either. I do have rg58/u and coax CATV cable on hand but the problem is that it is a difficult process to run the cable from my basement lab to the second floor attic and I only o want to do it once. Originally, I was going to penetrate the roof at the ridgeline and install the antenna on a one foot but I understand it is possible to receive singles from under the plywood/asphalt shingle roof. Is it worth a penetration of the roof? Jeff ___ 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] 58532a ANTENNA CABLE?
Besides, they smile a lot, so they must be happy :-) Didier -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Jean-Louis Oneto Sent: Thursday, March 27, 2008 6:11 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] 58532a ANTENNA CABLE? I never heard a clam complain, so... ;-} Jean-Louis Oneto - Original Message - From: [EMAIL PROTECTED] To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Thursday, March 27, 2008 10:53 PM Subject: Re: [time-nuts] 58532a ANTENNA CABLE? Hi Jeff- I have only used SatStat with my Z3801A, and it did take a while to get it set up right under XP. I much prefer Tboltmon for the Thunderbolt. Now that both are functional, I can start playing with them. I found that the Z3801A with the std HP antenna and recommended cable didn't work very well with the antenna in the garage (no plywood, 1x6s and 3 layers of asphalt shingles), it took forever to acquire sats and would lose the lock at the drop of a hat. It had to go out in the weather to be stable. On the other hand, the Thunderbolt antenna is in the corner of the garage, tilted at an angle, with hanging bicycles on one side and 19 racks on another, and is happy as a clam. Are clams happy? I've always wondered about that saying... -Dave No virus found in this outgoing message. Checked by AVG. Version: 7.5.519 / Virus Database: 269.21.8/1339 - Release Date: 3/22/2008 4:43 PM ___ 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] Tboltmon Serial Port Selection...??
Hello, All-- Can anyone tell me why, when I click on the Tboltmon icon associated with my Trimble Thunderbolt, that a little Serial Port Selecton window pops up and why does my T-bolt only run after selecting COM-4? Why can't this be selected once and then forgotten about? It seems like an un-necessary step. Thanks!! Mike Baker WA4HFR Micanopy, FL ___ 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] Tboltmon Serial Port Selection...??
I wish I knew how to bypass that too, so if you find out, please post the answer back here. On the other hand, if you have not already noticed, if the Tbolt is up and running and plugged in the serial port when the computer boots, your mouse will appear possessed. It is a Windows feature where the OS thinks the Tbolt is a serial mouse, and it is converting the data stream into mouse movements. And no, it does not work like a navigation system :-) Doing a Google search led me to the settings that have to be changed in Windows to disable this feature. I forgot the exact steps now (Control Panel - Hardware Manager - disable Serial Mouse driver). Didier KO4BB -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Michael Baker Sent: Thursday, March 27, 2008 6:43 PM To: time-nuts@febo.com Subject: [time-nuts] Tboltmon Serial Port Selection...?? Hello, All-- Can anyone tell me why, when I click on the Tboltmon icon associated with my Trimble Thunderbolt, that a little Serial Port Selecton window pops up and why does my T-bolt only run after selecting COM-4? Why can't this be selected once and then forgotten about? It seems like an un-necessary step. Thanks!! Mike Baker WA4HFR Micanopy, FL ___ 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 incoming message. Checked by AVG. Version: 7.5.519 / Virus Database: 269.21.8/1339 - Release Date: 3/22/2008 4:43 PM No virus found in this outgoing message. Checked by AVG. Version: 7.5.519 / Virus Database: 269.21.8/1339 - Release Date: 3/22/2008 4:43 PM ___ 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] Tboltmon Serial Port Selection...??
In a message dated 27/03/2008 23:45:09 GMT Standard Time, [EMAIL PROTECTED] writes: Can anyone tell me why, when I click on the Tboltmon icon associated with my Trimble Thunderbolt, that a little Serial Port Selecton window pops up and why does my T-bolt only run after selecting COM-4? Why can't this be selected once and then forgotten about? It seems like an un-necessary step. I get the same pop up but have always assumed it was to allow for the possibiliy that you might have Tbolts connected to more than one, or all, of those sixteen possible ports, so giving you the option to choose which one to monitor. I guess it only runs after you select COM4 because that's the port where it sees your Thunderbolt. I've never considered it to be a significant inconvenience. regards Nigel GM8PZR ___ 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] Tboltmon Serial Port Selection...??
Mike, I don't believe the software has any option for saving a serial port selection. At least I have never found one. It defaults to COM1. I use a USB/RS-232 converter and COM 2 because COM 1 on my laptop is in use by another application. I have to select COM2 every time I start the program. I don't do it that often so it is only a minor annoyance. As for why it only works on COM 4 on your PC, I would need a bit more information but I can speculate. Does your PC have the older RS-232 or newer USB serial ports? If you have the former, then the Trimble is connected to COM4. If you are using USB ports and a USB/RS-232 adapter (s) then the adapter has assumed the COM4 identifier when it was plugged into the USB port. When a USB/RS-232 adapter is plugged into a USB port it assumes a COMn identifier, usually the next available one. You may find that the system has already defined COM1, COM2, and COM3. This can happen if you move a USB/RS-232 adapter to a different USB port or have several adapters. In the following steps I am assuming you are using a Windows PC running XP and have USB ports and are using a USB/RS-232 adapter(s). If so go to Control Panel and open the System folder. Click on the Hardware tab. On the Hardware page click the Device Manager button. Click on the + sign next to Ports (COM LPT). You will see a list of COM ports defined on your system. If you don't see COM1 defined in the list then you COULD change the COM4 port to COM1. Here is how. Right click the COM4 entry. Click Properties. Click Port Settings. Click Advanced. Find the COM Port Number: pull down box. You should see COM4 in the box. Click the down arrow and select COM1. Click OK. Click OK until you are back to the Device Manager screen where you started. You should see COM1 listed as one of the ports. It may be necessary to close and reopen the Device Manager to see the change. Good luck. Ken, WA2LBI On Thu, Mar 27, 2008 at 7:43 PM, Michael Baker [EMAIL PROTECTED] wrote: Hello, All-- Can anyone tell me why, when I click on the Tboltmon icon associated with my Trimble Thunderbolt, that a little Serial Port Selecton window pops up and why does my T-bolt only run after selecting COM-4? Why can't this be selected once and then forgotten about? It seems like an un-necessary step. Thanks!! Mike Baker WA4HFR Micanopy, FL ___ 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] Tboltmon Serial Port Selection...??
Quoth Didier Juges at 2008-03-28 11:03... I wish I knew how to bypass that too, so if you find out, please post the answer back here. ... It is a Windows feature where the OS thinks the Tbolt is a serial mouse, and it is converting the data stream into mouse movements. And no, it does not work like a navigation system :-) ftp://ftp.trimble.com/pub/sct/embedded/bin/TrimbleGPSMonitor_V1-05-0.zip Extract the PDF manual from the zip file - gives instructions which should help. Basically, if Windows 'sees' a constant input stream from a serial device, it foolishly assumes that what is connected is a mouse. Glad I don't use Windows ;-) Cheers M -- Matthew Smith Smiffytech - Technology Consulting Web Application Development Business: http://www.smiffytech.com/ Personal: http://www.smiffysplace.com/ LinkedIn: http://www.linkedin.com/in/smiffy ___ 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] TADD-1 six channel RF distribution amplifier
I'm thinking about using the TAPR TADD-1 six channel RF distribution amplifier to distribute the 10MHz output of my Trimble Thunderbolt to a few pieces of test equipment. What does the TADD-1 do to the phase noise characteristics of its outputs as compared to the phase noise characteristics of its input? Improve? Degrade? Little or no change? Thanks. Steve K8JQ -- Read The Patriot It's Right -- It's Free http://PatriotPost.US/subscribe/ Veritas vos Liberabit ___ 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] Tboltmon Serial Port Selection...??
Marty, Thanks for the link, I did not know about this new software. I will try it. The manual appears well done too. Didier KO4BB -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Matthew Smith Sent: Thursday, March 27, 2008 8:02 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Tboltmon Serial Port Selection...?? Quoth Didier Juges at 2008-03-28 11:03... I wish I knew how to bypass that too, so if you find out, please post the answer back here. ... It is a Windows feature where the OS thinks the Tbolt is a serial mouse, and it is converting the data stream into mouse movements. And no, it does not work like a navigation system :-) ftp://ftp.trimble.com/pub/sct/embedded/bin/TrimbleGPSMonitor_ V1-05-0.zip Extract the PDF manual from the zip file - gives instructions which should help. Basically, if Windows 'sees' a constant input stream from a serial device, it foolishly assumes that what is connected is a mouse. Glad I don't use Windows ;-) Cheers M No virus found in this outgoing message. Checked by AVG. Version: 7.5.519 / Virus Database: 269.21.8/1339 - Release Date: 3/22/2008 4:43 PM ___ 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] TADD-1 six channel RF distribution amplifier
Steve wrote: I'm thinking about using the TAPR TADD-1 six channel RF distribution amplifier to distribute the 10MHz output of my Trimble Thunderbolt to a few pieces of test equipment. What does the TADD-1 do to the phase noise characteristics of its outputs as compared to the phase noise characteristics of its input? Improve? Degrade? Little or no change? Thanks. Steve K8JQ Like any distribution amplifier it always degrades the signal phase noise. Whether the amount of degradation is significant or not depends on the phase noise characteristics of your source. If your signal source phase noise is 10dB greater than the intrinsic phase noise of the distribution amplifier than the increase in the phase noise at the distribution amplifier is relatively insignificant. Thus you need to know the phase noise characteristics of your source and of the distribution amplifier (when set to the gain you need). The phase noise characteristics of the distribution amplifier vary with its gain. The phase noise of your source and a distribution amplifier vary with the frequency offset at which they are measured. What source are you intending to use? Do you know its phase noise characteristics? Bruce ___ 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] Racal-Dana 1992 switches
Matt, Not seeing a better alternative posted for the Racal 1992, and having dozens of similar bad Toko switches on some Pacific Measurements 1038-N10 Scalar Analyzers, I decided to buy a bunch of the Jameco ones and give it a try. Definitely not a form fit replacement. But if you're not too asthetically picky they do fit. The leads can be manually flattened with a pair of needle nose pliers and reformed to fit under and down to match the closer hole spacing. Also clip off the small plastic alignment pins to allow the switches to sit flush on the board. The process only takes a couple of seconds per switch. A lot quicker than removal of the original switches. The real catch is the hole size in the 1992 original switch layout is a couple of sizes smaller on one pin than the other. Using a #54 drill bit (no bigger) you can clean the hole out and enlarge it without taking the plated thru barrel out of the holes on that one side. All my switches are in and working. I didn't even put the keycaps back on as all the manual lead forming didn't necessarily center within the original panel cutouts and the plastic posts are adequate for use as switches. The numerical keys in center keypad may require Dan's epoxy trick. Haven't gotten to that yet. Now the real question is... is there a clever way to make the Racal 1992 readout the difference in µHz between two GPS disciplined oscillators? My only other counter, an HP5384A, is offscale at 10.000 000.000 MHz . I'm referencing the counter with one Lucent RFTG-m-XO and clocking a Lucent RFTGm-II-XO. Things are working well enough to be beyond my counter's ability to see any jitter. The Racal says nanosecond time interval counter, so I bet there's a way to subtract and increase the resolution similar to an HP53131? tnx, Charles K4CSO Duluth, GA - Original Message - From: Matt Ettus [EMAIL PROTECTED] To: [EMAIL PROTECTED]; Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Monday, March 24, 2008 1:46 PM Subject: Re: [time-nuts] Racal-Dana 1992 switches On Mon, Mar 10, 2008 at 8:47 AM, Dan Rae [EMAIL PROTECTED] wrote: David McGaw wrote: Does anyone know of a source of push-button switches for the Racal-Dana 1992? I have one that over half are bad. No luck from Racal-Dana or their service house. The original makers of that switch (Omron?) stopped making them years ago. I wonder why? The last time I did this I found a switch at Jameco that was a near exact replacement. The only difference was that the button was a little too loose a fit and needed a dab of epoxy inside to hold it firmly in place. These have been working in mine now for at least five years. The type I used was KIE22 (29 cents each in 100s), however the ones I got then with a cross section shape blue plunger do not look exactly the same as the ones pictured in the current on line catalog. Some further research is indicated obviously... Once they start to go they will all need to be replaced, I'm afraid. I bought the ones in the catalog, but they don't fit. The footprint is bigger, for one thing. Matt ___ 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] Racal-Dana 1992 switches
I fixed the switches on my Pacific Measurements 1038-N10 by adding a small coil spring to the insides of each switch. I don't remember it being very hard to do. There is even a place in the center of each switch that is perfect for putting the spring. The springs were something I had around in bulk, and were cut to length with a pair of dikes that I didn't care about. -Chuck Harris Charles S. Osborne wrote: Matt, Not seeing a better alternative posted for the Racal 1992, and having dozens of similar bad Toko switches on some Pacific Measurements 1038-N10 Scalar Analyzers, I decided to buy a bunch of the Jameco ones and give it a try. ___ 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] TADD-1 six channel RF distribution amplifier
Bruce Griffiths wrote: Steve wrote: I'm thinking about using the TAPR TADD-1 six channel RF distribution amplifier to distribute the 10MHz output of my Trimble Thunderbolt to a few pieces of test equipment. What does the TADD-1 do to the phase noise characteristics of its outputs as compared to the phase noise characteristics of its input? Improve? Degrade? Little or no change? Thanks. Steve K8JQ I've been using a TADD-1 for about 6-months now and I'm quite happy with it. You certainly can't beat the price. I added the optional 10MHz BPF and tuned it with a tracking generator and spectrum analyzer. The outputs are very clean. I've never tried to measure phase noise, but the op amps and the rest of the circuit seem to be good choices to me. tvb did some analysis of the box you might find interesting: http://www.leapsecond.com/pages/tadd-1/ jeff ___ 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] TADD-1 six channel RF distribution amplifier
Jeff Mock wrote: Bruce Griffiths wrote: Steve wrote: I'm thinking about using the TAPR TADD-1 six channel RF distribution amplifier to distribute the 10MHz output of my Trimble Thunderbolt to a few pieces of test equipment. What does the TADD-1 do to the phase noise characteristics of its outputs as compared to the phase noise characteristics of its input? Improve? Degrade? Little or no change? Thanks. Steve K8JQ I've been using a TADD-1 for about 6-months now and I'm quite happy with it. You certainly can't beat the price. I added the optional 10MHz BPF and tuned it with a tracking generator and spectrum analyzer. The outputs are very clean. I've never tried to measure phase noise, but the op amps and the rest of the circuit seem to be good choices to me. tvb did some analysis of the box you might find interesting: http://www.leapsecond.com/pages/tadd-1/ jeff Jeff As John Ackermann has often pointed out using a high Q bandpass filter is a particularly bad idea if phase shift tempco is important. The best way to eliminate harmonics is to use high Q traps tuned to the unwanted harmonics, these have litle phase shift (and associated tempco) at the fundamental. If you do use a high Q bandpass filter it may be necessary to regulate its temperature to stabilise its phase shift. Some care in selection of filter components is also required to avoid significantly increasing flicker phase noise. John has far some distribution amplifier phase noise comparison data at: http://www.febo.com/pages/amplifier_phase_noise/ Bruce ___ 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.
