Re: [time-nuts] Optical time sync
Hal Murray wrote: > Why not? > > Diesel-electric locomotives do electrical conversions because it's more > efficient than mechanical gears. > > Some high voltage transmission lines are DC. The conversion sites on each > end must be interesting. > Especially when they use mercury arc rectifiers. Thyristor stacks arent nearly as imposing. 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] Favorite DC power Supply?
In message <[EMAIL PROTECTED]>, "Ulrich Bangert" writes: >Patrick, > >since I own it I am in love with my HP6632A power supply. I can recommend the HP 6626A as well, it has four outputs (2x25W, 2x50W) and each output has 2x2 ranges for current and voltage. You need to make your own cabling for the outputs, since it only has back panel outputs. Ohh, and no dial-knob... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [EMAIL PROTECTED] | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ 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] Favorite DC power Supply?
Hello Everyone. I also own an HP 6632A DC supply. This is a great beast. Its sink capability is just great to test other power supplies or discharge NiCads. I have a more powerful DC electronic load, but I almost never use it. Its only drawback is its size - rackmount - which makes it a bit large for small benches. In my case, I made room for it! Mine did not have the optional front banana jacks, but now it does... Everything is ready inside for it, with PCB-mounted lugs right behind the faceplate. Even jack locations are pre-drilled. All you have to do is drill through the thin aluminum plate that covers the front. ~ $100-$150 on Ebay. A good deal. Bert, VE2ZAZ __ Ask a question on any topic and get answers from real people. Go to Yahoo! Answers and share what you know at http://ca.answers.yahoo.com ___ 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] Favorite DC power Supply?
Hi Bert: Thanks for your description of the 6632A. I didn't realize they could sink current. There are three 100W supplies in this family: 6632A 20V 5A 6633A 50V 2A 6634A 100V 1A I have the 50V model on the way, much better for 28 volt equipment. The load capacity is not as high as the American Reliance EL1132 which is rated 300 W so it gets to stay. http://www.prc68.com/I/EL1132.shtml Have Fun, Brooke Clarke http://www.prc68.com/P/Prod.html Products I make and sell http://www.prc68.com/Alpha.shtml All my web pages listed based on html name http://www.PRC68.com http://www.precisionclock.com http://www.prc68.com/I/WebCam2.shtml 24/7 Sky-Weather-Astronomy Web Cam Bert, VE2ZAZ wrote: > Hello Everyone. > > I also own an HP 6632A DC supply. This is a great beast. Its sink capability > is just great to test other power supplies or discharge NiCads. I have a more > powerful DC electronic load, but I almost never use it. Its only drawback is > its size - rackmount - which makes it a bit large for small benches. In my > case, I made room for it! > > Mine did not have the optional front banana jacks, but now it does... > Everything is ready inside for it, with PCB-mounted lugs right behind the > faceplate. Even jack locations are pre-drilled. All you have to do is drill > through the thin aluminum plate that covers the front. > > ~ $100-$150 on Ebay. A good deal. > > Bert, VE2ZAZ > > > > __ > Ask a question on any topic and get answers from real people. Go to Yahoo! > Answers and share what you know at http://ca.answers.yahoo.com > ___ > 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] Favorite DC power Supply?
Hi Brooke and others! Have a 6624A and a 6622A. Have yet to arrange a good front panel for their outputs. The thing that bothers me is the rather large amount of noise they generate. The fan is LOUD compared to my other instruments. Anyone done a safe conversion on the fan solution to these nice beasts_ -- Björn On Fri, 2008-05-02 at 09:20 -0700, Brooke Clarke wrote: > Hi Bert: > > Thanks for your description of the 6632A. I didn't realize they could sink > current. There are three 100W supplies in this family: > 6632A 20V 5A > 6633A 50V 2A > 6634A 100V 1A > > I have the 50V model on the way, much better for 28 volt equipment. > The load capacity is not as high as the American Reliance EL1132 which is > rated > 300 W so it gets to stay. http://www.prc68.com/I/EL1132.shtml > > Have Fun, > > Brooke Clarke > http://www.prc68.com/P/Prod.html Products I make and sell > http://www.prc68.com/Alpha.shtml All my web pages listed based on html name > http://www.PRC68.com > http://www.precisionclock.com > http://www.prc68.com/I/WebCam2.shtml 24/7 Sky-Weather-Astronomy Web Cam > > > Bert, VE2ZAZ wrote: > > Hello Everyone. > > > > I also own an HP 6632A DC supply. This is a great beast. Its sink > > capability is just great to test other power supplies or discharge NiCads. > > I have a more powerful DC electronic load, but I almost never use it. Its > > only drawback is its size - rackmount - which makes it a bit large for > > small benches. In my case, I made room for it! > > > > Mine did not have the optional front banana jacks, but now it does... > > Everything is ready inside for it, with PCB-mounted lugs right behind the > > faceplate. Even jack locations are pre-drilled. All you have to do is drill > > through the thin aluminum plate that covers the front. > > > > ~ $100-$150 on Ebay. A good deal. > > > > Bert, VE2ZAZ > > > > > > > > __ > > Ask a question on any topic and get answers from real people. Go to Yahoo! > > Answers and share what you know at http://ca.answers.yahoo.com > > ___ > > 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] Favorite DC power Supply?
Not me, I have too many power supplies now. But, As they have remote voltage sensing and you need a panel anyway why not connect long cables to put them under the table or where the noise is less of a concern. As a plus you could have more space where you need it and the flexibility to have a more mobile panel to move around the room. I have no idea about cable size or max length but it should be listed somewhere. Stanley - Original Message From: Björn Gabrielsson <[EMAIL PROTECTED]> To: [EMAIL PROTECTED]; Discussion of precise time and frequency measurement Sent: Friday, May 2, 2008 1:37:21 PM Subject: Re: [time-nuts] Favorite DC power Supply? Hi Brooke and others! Have a 6624A and a 6622A. Have yet to arrange a good front panel for their outputs. The thing that bothers me is the rather large amount of noise they generate. The fan is LOUD compared to my other instruments. Anyone done a safe conversion on the fan solution to these nice beasts_ -- Björn On Fri, 2008-05-02 at 09:20 -0700, Brooke Clarke wrote: > Hi Bert: > > Thanks for your description of the 6632A. I didn't realize they could sink > current. There are three 100W supplies in this family: > 6632A 20V 5A > 6633A 50V 2A > 6634A 100V 1A > > I have the 50V model on the way, much better for 28 volt equipment. > The load capacity is not as high as the American Reliance EL1132 which is > rated > 300 W so it gets to stay. http://www.prc68.com/I/EL1132.shtml > > Have Fun, > > Brooke Clarke > http://www.prc68.com/P/Prod.html Products I make and sell > http://www.prc68.com/Alpha.shtml All my web pages listed based on html name > http://www.PRC68.com > http://www.precisionclock.com > http://www.prc68.com/I/WebCam2.shtml 24/7 Sky-Weather-Astronomy Web Cam > > > Bert, VE2ZAZ wrote: > > Hello Everyone. > > > > I also own an HP 6632A DC supply. This is a great beast. Its sink > > capability is just great to test other power supplies or discharge NiCads. > > I have a more powerful DC electronic load, but I almost never use it. Its > > only drawback is its size - rackmount - which makes it a bit large for > > small benches. In my case, I made room for it! > > > > Mine did not have the optional front banana jacks, but now it does... > > Everything is ready inside for it, with PCB-mounted lugs right behind the > > faceplate. Even jack locations are pre-drilled. All you have to do is drill > > through the thin aluminum plate that covers the front. > > > > ~ $100-$150 on Ebay. A good deal. > > > > Bert, VE2ZAZ > > > > > > > > __ > > Ask a question on any topic and get answers from real people. Go to Yahoo! > > Answers and share what you know at http://ca.answers.yahoo.com > > ___ > > 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. Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ ___ 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] Favorite Power Supply
Hi; I bought a number of these for work and we've been very pleased with them: The GP1305TP version. One fixed +5, and two variable (but they can be locked for eg: +/- 15) outputs. > http://www.testequipmentdepot.com/ezdigital/gp1305.htm Tom Frank, KA2CDK ___ 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] Favorite DC power Supply?
I have a Kikusui PAR80A that I've become attached to. 0-80Vdc @1A, 0-8Vdc @10A with 1mA resolution in a small but heavy box. Single output, but I have other PSs if I need more. What would one use 5Vdc @ 100A supplies for these days? I found 2 HP units in the garage last weekend. -Dave -- Original message -- From: Patrick <[EMAIL PROTECTED]> > Hi Everyone > > I have been using a power supply from an old computer for my bench set > up. I am finally going to break down and purchase a proper variable > power supply. One channel ought to do for me and I don't need a > programmable one. > > Does anyone have a recommendation for a supply under $600 U.S? Any > garbage ones to avoid? > > Thanks in advance-Patrick > > ___ > 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] Favorite DC power Supply?
On Fri, 02 May 2008 22:24:11 +, [EMAIL PROTECTED] wrote: >What would one use 5Vdc @ 100A supplies for these days? I found 2 HP units in >the garage last weekend. Set each one to 6 volts, hook 'em in series and use 'em to run big 12 volt loads. I ran a homemade true uninterruptible power supply for years using that lashup. Remember when those things were a dime a dozen at swap meets? Scarce as hen's teeth now. John -- John De Armond See my website for my current email address http://www.neon-john.com http://www.johndearmond.com <-- best little blog on the net! Tellico Plains, Occupied TN Ever stop to think, and forget to start again? ___ 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] Favorite DC power Supply?
> From: Patrick <[EMAIL PROTECTED]> > >> Hi Everyone >> >> I have been using a power supply from an old computer for my bench set >> up. I am finally going to break down and purchase a proper variable >> power supply. One channel ought to do for me and I don't need a >> programmable one. >> >> Does anyone have a recommendation for a supply under $600 U.S? Any >> garbage ones to avoid? >> >> Thanks in advance-Patrick I'm almost embarrassed to admit this, but I'm partial to the old HP/Harrison 6200B supplies. They do 0-40 volts at .75A, or 0-20 volts at 1.5A. CC and CV modes, but you have to live with an analog meter. They don't take much space, and there are usually plenty on eBay for around $50. Some of them require a bit of refurb, but they're easy to work on and there's a manual available at the Agilent manual web site. I have three of them (along with a newer Agilent supply with digital readout but similar rating) on a shelf above my workbench, and a couple of spares tucked away. For demanding applications like looking at ultra stable or ultra low noise OCXOs, I use a "super regulator" board that's available from http://www.at-view.co.uk/alwsr.htm in the UK as a bare board, board with low noise op-amp (surface mount) installed, or complete unit. Using the 6200B to drive one of these boards built for 15 or 24 volt output works very nicely. John ___ 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] Favorite DC power Supply?
Useful if you need to check integrity of high current crimped joints, connectors etc- the supply is bound to be a switcher, so if you can figure out how to tweak the voltage over a goodly range with existing ccty,, then it's a done deal- otherwise you may need to build an external series regulator (adjustable series resistor!) DaveB, NZ - Original Message - From: <[EMAIL PROTECTED]> To: "Discussion of precise time and frequency measurement" ; "Discussion of precise time and frequency measurement" Sent: Saturday, May 03, 2008 10:24 AM Subject: Re: [time-nuts] Favorite DC power Supply? >I have a Kikusui PAR80A that I've become attached to. 0-80Vdc @1A, >0-8Vdc @10A with 1mA resolution in a small but heavy box. Single >output, but I have other PSs if I need more. > > What would one use 5Vdc @ 100A supplies for these days? I found 2 > HP units in the garage last weekend. > > -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] Favorite DC power Supply?
Quoth Neon John at 2008-05-03 08:16... > Set each one to 6 volts, hook 'em in series and use 'em to run big 12 volt > loads. I ran a homemade true uninterruptible power supply for years using > that lashup. OK, whilst we're deviating from time a little, I would like to put a time and power supply question to my learned colleagues: I am building two GPS-driven devices, an NTP server based on an ancient single board computer and a Nixie clock. Our power here is not what one might call reliable - we are stuck on a spur of a very long 19kV, single wire, earth return supply which plays up a) when there is a thunderstorm within 200 miles and b) when it feels like it. Whilst I could incorporate mains power supplies into both units, I like to avoid getting mains in my constructions if I can avoid it. The SBC has a PC-104 automotive PSU fitted and I'm building the supplies for the Nixie clock (+5V, +12V, +170V) to operate from about 11.9V (shutdown if less) to 15V DC. My thought was to integrate a UPS component into the design by connecting these to 12V 7Ah sealed lead acid batteries, which I can get for just over $20 AUD a piece. If I were to do this, would it be sufficient to power the units from a 13.8V supply? I believe this to be within the voltage range for float-charging the batteries so was guessing that this may be a simple way to provide uninterrupted power to my gear. 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.
Re: [time-nuts] Favorite DC power Supply?
At 06:14 PM 5/2/2008, John Ackermann N8UR wrote: >I'm almost embarrassed to admit this, but I'm partial to the old >HP/Harrison 6200B supplies. They do 0-40 volts at .75A, or 0-20 volts I'm not embarrassed to admit that I love my 6200B. I took it in to work so that I could use it daily. I do wish that it had two meters and OVP, however. -- newell N5TNL ___ 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] FW: Favorite DC power Supply?
Here are my 2 favorite power supplies. http://www.ko4bb.com/Test_Equipment/Power_Supplies.png The one on the left is a 30V/3A supply. The current limit is adjustable with a 10 turns pot, so it can be precisely set. I only use 3 turns of the 10 turns pot, so that one turn is one A, resolution is 20mA. I find it extremely convenient to be able to precisely set the current limit without having to use another instrument. When in current limit, the lower LED turns on. It has a variable speed fan, so that while small, I can use it at any voltage/current setup, but it is only noisy when it's working hard. The transformer uses a dual C tape wound core, and while small, it occupies the vast majority of the space in the box, the rest being the filter cap. Ther electronics uses whatever space was left around those parts. The heat sink in on the back side, in the open, with the fan blowing across it. The meter can display V or I, and when you press the small push-button, the scale is 1/10th (0.3A FS). It is very low noise and stable, with a good voltage reference. It will also sink current at the programmed value, convenient to check batteries. It was completed about 10 years ago, but I have improved it since with a better reference, better op-amps and better compensation for better ripple/noise/transient response. The one on the right is an oldie, I started it while in college. People who were not yet born now have their own children going to school... It is a tracking, dual adjustable output supply, with a 10 turns pot to adjust the voltage in 2 ranges, 0-10 or 10-20V with about 0.5A max current. This one is not current limited, but it trips very fast and shuts down if the current is exceeded (it has very small output capacitance). I found that preferable when working on sensitive analog circuits. You can set it to 10V and connect it to the B-E junction of a small bipolar transistor without blowing it. It also has a third output, nominal 5V/0.5A that is adjustable in voltage or can be switched as a constant current output 0.05 to 0.5A) with the screwdriver type front panel potentiometer. It is also convenient to charge batteries. I also have a number of commercial supplies, by HP, Topward and Powermate, with higher voltage and/or current capability when needed, but these are the ones I use all the time. Both are pretty small, the big one is 16 x 7 cm (6.3"W x 2.75"H) across the front (the current fan is a little taller...) That's another reason I use them all the time. Didier KO4BB Internal Virus Database is out-of-date. Checked by AVG. Version: 7.5.519 / Virus Database: 269.22.5/1358 - Release Date: 4/3/2008 6:36 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] Favorite DC power Supply?
On Sat, 03 May 2008 08:58:58 +0930, Matthew Smith <[EMAIL PROTECTED]> wrote: >I am building two GPS-driven devices, an NTP server based on an ancient >single board computer and a Nixie clock. Our power here is not what one >might call reliable - we are stuck on a spur of a very long 19kV, single >wire, earth return supply which plays up a) when there is a thunderstorm >within 200 miles and b) when it feels like it. Does your power system STILL use ground return? Are you sure there isn't a neutral return on the primary feed? If not then WOW. I bet it's interesting walking around the earth ground in dry weather. A shocking experience. >My thought was to integrate a UPS component into the design by >connecting these to 12V 7Ah sealed lead acid batteries, which I can get >for just over $20 AUD a piece. If I were to do this, would it be >sufficient to power the units from a 13.8V supply? I believe this to be >within the voltage range for float-charging the batteries so was >guessing that this may be a simple way to provide uninterrupted power to >my gear. Change that voltage to whatever float voltage your batteries want and it'll work peachy. That is effectively the way I had my homemade UPS connected - the two big honkin' 100 amp supplies connected to a pair of trolling batteries. Also connected to the trolling batteries was a non-switch-mode, pure square wave inverter, a Tripplite 1kw unit. Yep, with about 2 dozen 2N3055 TO-3 transistors bolted down each side and about 60 lbs of iron and copper in the transformer. A simple power blocking oscillator design with the *deluxe* frequency control board, a 555 timer running at 60hz injection-locking the power oscillator. It had no concept of overload shutdown so it was good for much more than 1kw short term until the whole unit got hot enough to boil eggs! Seems like that sucker cost around $600. Everything that everybody said wouldn't work on a square wave inverter did. Second generation HP laserjet, 386 vintage computer power supplies, CRTs, smart terminals, TrailBlazer modems (remember those?), etc. I started one of the very first for-pay ISPs (dixie.com). It was hosted on a 33mhz 386 PC with 12mb of RAM ($$$) and an actual gig of full height 5.25" hard drives ($$) running Interactive Unix ($2k just for the OS). That machine supported 2 developers plus 16 2400 bps dial-up modems and a couple of Trailblazers for news feeds. Demonstrates just what a pig winders is! Had a hell of a time getting that Bell B*tch to drag a T-1 line to my basement where all this stuff was operated from. I later added a second machine and modem rack and another homemade UPS. Same architecture except that I couldn't find any more 100 amp supplies on a moment's notice. I instead used a 150 amp unregulated supply that came out of a Univac mainframe. A motor-operated variac ahead of the transformer "regulated" the voltage. At the operator's console was a voltmeter and a momentary on-off-on toggle switch. Whomever was sysop at the time had the duty to watch the voltage and run the variac up and down as needed. We always intended to build an automatic regulator but never got a round tuit. At $20 a month per subscriber I just couldn't make the numbers work for the long term so just about the time Mosaic hit the scene, I shut everything down, sold most of the hardware, let the registration on dixie.com expire and left the computer field to open a restaurant. *sigh*. Back to the present. Here in the US, inverters are so cheap that one could be applied to each load. No idea what conditions are there but here I can get a 750 watt inverter for under $50 and a 2000 watt unit from Harbor Freight for $149. John -- John De Armond See my website for my current email address http://www.neon-john.com http://www.johndearmond.com <-- best little blog on the net! Tellico Plains, Occupied TN It isn't Global Warming It's Jerry Falwell arriving in hell. ___ 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.
