Re: [time-nuts] Thunderbolt Supply commercial option
One commercial linear power supply that works well for the T-bolt is Power one's HTAA-16W. This is a 16W triple output 5V 2A +12V (or 15) 0.4A -12V 0.4A unit. While 0.4 is under the warm up rating for the T-bolt it's OK for running. The fact that we are well under running it on +5V and -12V means the +12 is OK at 0.6 to 0.7A for short periods. The 10% derating for 50Hz v 60Hz tells me the transformer is the limiting component. Spreading the load across ratings is OK. They are available new and surplus. New is about $100 but surplus they run 99p to £20. Robert G8RPI. ___ 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] Thunderbolt Supply - Final word
Fleming was perfectly located, in spite of himself, the problem of all groups and clubs in the world. There is always an imbalance between theory, practical experience and implementation. There are always good advice, but hardly any solutions. I invite us all to use most of the iron to finish the process that starts from the theory, design and ending with implementation. Otherwise we run the risk to celebrate itself without producing anything of working. Luciano Luciano P. S. Paramithiotti -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Flemming Larsen Sent: giovedì 17 febbraio 2011 3.19 To: shali...@gmail.com; Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Thunderbolt Supply - Final word Didier et al, I did not ask for, and did not expect rocket science. Just a simple solution or advice from some of the much more experienced people on this list. I am trying to put my equipment together after having had everything in storage for several years. Being retired and on a limited budget, I am trying to make what I have work, rather than trying to reinvent the wheel. Given enough time and an unlimited budget, I'm sure that I could come up with a better solution. For the time being, I was hoping that someone on the list could point me to a simple solution that would fit my needs and budget, thinking that lots of other people have had to go through similar steps with the number of Chinese switching power supplies that were sold with the Thunderbolts, both here on the list and on eBay. just care and good engineering. I totally agree. I did that professionally for many years, but now I'm retired and no longer have access to the resources and test equipment I used to have access to at work. Other people on the list have access to better resources than I do and many people have more experience than I do, especially when it comes to switching power supplies. I appreciate all the advice I was given, although nobody pointed me to a circuit with component values that I could simply duplicate, instead of having to go the whole process of getting my books off the shelf and do what others have already done. No matter now. UPS just brought me a nice linear power supply today. 5 volts @ 28 amps and +/-12 volts @ 3 amps. Although probably many times overkill for the application and as big as breadbox, this should probably work, and without the unnecessary need to add complex (or not) filters. Thanks again, -- Flemming LarsenOZ6OI/KB6ADSBerkeley, CA, USA Sent from my computer Sent from my Verizon Wireless BlackBerry ___ 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] Thunderbolt Supply - Final word
Precisely because most of us do not have access to much fancy test equipment (I am one of the lucky ones), there is no excuse for not using freely available, quality tools (assuming that you have a computer) like LT Spice. Of course, you have to be careful as the quality of the output from any simulation software will only be as good as the inputs you feed into it. However, used appropriately, it will save you hours on the bench, and avoid the pain and embarrassment of building something that may have a major flaw. Also, it allows you to verify that your circuit will work under conditions that may be difficult to experimentally create (such as aging, component tolerances and temperature). So when Bruce offers his advice based on Spice simulations, I pay attention. Didier KO4BB Sent from my Verizon Wireless BlackBerry -Original Message- From: Paramithiotti, Luciano Paolo S luciano.paramithio...@hp.com Sender: time-nuts-boun...@febo.com Date: Thu, 17 Feb 2011 08:37:24 To: Discussion of precise time and frequency measurementtime-nuts@febo.com Reply-To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Thunderbolt Supply - Final word Fleming was perfectly located, in spite of himself, the problem of all groups and clubs in the world. There is always an imbalance between theory, practical experience and implementation. There are always good advice, but hardly any solutions. I invite us all to use most of the iron to finish the process that starts from the theory, design and ending with implementation. Otherwise we run the risk to celebrate itself without producing anything of working. Luciano Luciano P. S. Paramithiotti -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Flemming Larsen Sent: giovedì 17 febbraio 2011 3.19 To: shali...@gmail.com; Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Thunderbolt Supply - Final word Didier et al, I did not ask for, and did not expect rocket science. Just a simple solution or advice from some of the much more experienced people on this list. I am trying to put my equipment together after having had everything in storage for several years. Being retired and on a limited budget, I am trying to make what I have work, rather than trying to reinvent the wheel. Given enough time and an unlimited budget, I'm sure that I could come up with a better solution. For the time being, I was hoping that someone on the list could point me to a simple solution that would fit my needs and budget, thinking that lots of other people have had to go through similar steps with the number of Chinese switching power supplies that were sold with the Thunderbolts, both here on the list and on eBay. just care and good engineering. I totally agree. I did that professionally for many years, but now I'm retired and no longer have access to the resources and test equipment I used to have access to at work. Other people on the list have access to better resources than I do and many people have more experience than I do, especially when it comes to switching power supplies. I appreciate all the advice I was given, although nobody pointed me to a circuit with component values that I could simply duplicate, instead of having to go the whole process of getting my books off the shelf and do what others have already done. No matter now. UPS just brought me a nice linear power supply today. 5 volts @ 28 amps and +/-12 volts @ 3 amps. Although probably many times overkill for the application and as big as breadbox, this should probably work, and without the unnecessary need to add complex (or not) filters. Thanks again, -- Flemming LarsenOZ6OI/KB6ADSBerkeley, CA, USA Sent from my computer Sent from my Verizon Wireless BlackBerry ___ 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] Thunderbolt Supply
Hi I would add a couple of surplus switcher coils to the setup and some good caps. The switcher likely puts out 60 KHz and that's what you want to kill. Something in the X.X mhy range and some reasonable caps (ceramic or very good plastic) should do the job. Bob On Feb 16, 2011, at 1:19 AM, Flemming Larsen wrote: This has gone overboard. As a sailor I'm careful about using that phrase. Thanks for all the suggestions and information. I;m now back to my original plan to use the Power-One +5V and +/- 15V switching power supply, followed by a pair of 7812/7912 voltage regulators for the + and - 12V. The power supply and Thunderbolt will be mounted in separate enclosures connected with a short(12) cable. I will add ferrite beads on both ends of the wires where they exit and enter the two enclosures, paralleled with 0.1 uF capacitors to ground. The 12 volt regulators will be filtered with 2200uF electrolytic capacitors on each input and 10uF on each output. The 7812/7912 regulators will be mounted on heatsinks mounted on spacers on the back of the enclosure. I am not sure what to do, if anything, to the +5 volt other than adding an inductor of the power-line filter variety in series. If I can find some feed-through capacitors of the threaded variety, I may add them to the back of the Thunderbolt enclosure to replace the original connector. All of this will be mounted on the back of a 1U rack panel. Now, if I could find the correct HP paint code ... -- Flemming LarsenOZ6OI/KB6ADSBerkeley, CA, USA ___ 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] Thunderbolt Supply
My original (red box) T-bolt runs off a 28VDC supply. For that, it has a built-in DC/DC converter. The specs are the same as they are for the more common (and more recent) version. You do not need rocket science to make a switcher quiet enough for most purposes, just care and good engineering. When circuits are extremely sensitive to supply noise (I mean by that way out of the ordinary sensitivity), the problem may be with the circuit design rather than with the supply. Didier KO4BB Sent from my Verizon Wireless BlackBerry -Original Message- From: Magnus Danielson mag...@rubidium.dyndns.org Sender: time-nuts-boun...@febo.com Date: Tue, 15 Feb 2011 10:47:31 To: time-nuts@febo.com Reply-To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] Thunderbolt Supply On 02/15/2011 04:18 AM, Charles P. Steinmetz wrote: Bob wrote: If all you are doing is running a Thunderbolt, you don't need a supply that's more quiet than most batteries. Most batteries are *very* quiet -- it takes heroic measures to get *any* actively regulated supply into that ballpark. Indeed, one might be tempted to run a Tbolt off of three batteries, each one charged by a low-noise, high-impedance current source that puts out about .05 CV more than the Tbolt draws. One could even turn the charging off for short periods of minimal noise operation, if the batteries were suitably sized. However, in either case I would be concerned that the drift of one or more of the battery voltages (poor absolute regulation) might introduce another source of XO drift -- but I have not tried it. This has gone overboard. The T-bolt generates digital noise all by itself. It's the OCXO which would benefit most from a clean supply and isolation from the rest of the T-bolt except that temp-sensor. Providing ultra-clean supplies to the digital logic would be overkill, as it would mess it up itself anyway. 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] Thunderbolt Supply - Final word
Didier et al, I did not ask for, and did not expect rocket science. Just a simple solution or advice from some of the much more experienced people on this list. I am trying to put my equipment together after having had everything in storage for several years. Being retired and on a limited budget, I am trying to make what I have work, rather than trying to reinvent the wheel. Given enough time and an unlimited budget, I'm sure that I could come up with a better solution. For the time being, I was hoping that someone on the list could point me to a simple solution that would fit my needs and budget, thinking that lots of other people have had to go through similar steps with the number of Chinese switching power supplies that were sold with the Thunderbolts, both here on the list and on eBay. just care and good engineering. I totally agree. I did that professionally for many years, but now I'm retired and no longer have access to the resources and test equipment I used to have access to at work. Other people on the list have access to better resources than I do and many people have more experience than I do, especially when it comes to switching power supplies. I appreciate all the advice I was given, although nobody pointed me to a circuit with component values that I could simply duplicate, instead of having to go the whole process of getting my books off the shelf and do what others have already done. No matter now. UPS just brought me a nice linear power supply today. 5 volts @ 28 amps and +/-12 volts @ 3 amps. Although probably many times overkill for the application and as big as breadbox, this should probably work, and without the unnecessary need to add complex (or not) filters. Thanks again, -- Flemming LarsenOZ6OI/KB6ADSBerkeley, CA, USA Sent from my computer Sent from my Verizon Wireless BlackBerry ___ 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] Thunderbolt Supply
On 02/15/2011 04:18 AM, Charles P. Steinmetz wrote: Bob wrote: If all you are doing is running a Thunderbolt, you don't need a supply that's more quiet than most batteries. Most batteries are *very* quiet -- it takes heroic measures to get *any* actively regulated supply into that ballpark. Indeed, one might be tempted to run a Tbolt off of three batteries, each one charged by a low-noise, high-impedance current source that puts out about .05 CV more than the Tbolt draws. One could even turn the charging off for short periods of minimal noise operation, if the batteries were suitably sized. However, in either case I would be concerned that the drift of one or more of the battery voltages (poor absolute regulation) might introduce another source of XO drift -- but I have not tried it. This has gone overboard. The T-bolt generates digital noise all by itself. It's the OCXO which would benefit most from a clean supply and isolation from the rest of the T-bolt except that temp-sensor. Providing ultra-clean supplies to the digital logic would be overkill, as it would mess it up itself anyway. 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] Thunderbolt Supply
On Tue, 2011-02-15 at 10:47 +0100, Magnus Danielson wrote: This has gone overboard. The T-bolt generates digital noise all by itself. It's the OCXO which would benefit most from a clean supply and isolation from the rest of the T-bolt except that temp-sensor. Considering the T-bolt has 3 supplies which rail is the one that is most important to keep clean My main interest is the best possible phase noise and spur performance as the 10MHz output is feeding a high quality SDR Providing ultra-clean supplies to the digital logic would be overkill, as it would mess it up itself anyway. I guess what I am wondering, considering I already have a very low noise, stable, battery backed 12V (13.8V really) system in the shack can I use that along with a small dual rail DC-DC converter and still get very good performance -- 73 Brendan EI6IZ ___ 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] Thunderbolt Supply
Hi The same board with all the logic crud on it has the 10 MHz signal amps on it. Same supply / same ground for it all. There very much is a practical limit here. Bob On Feb 15, 2011, at 4:47 AM, Magnus Danielson wrote: On 02/15/2011 04:18 AM, Charles P. Steinmetz wrote: Bob wrote: If all you are doing is running a Thunderbolt, you don't need a supply that's more quiet than most batteries. Most batteries are *very* quiet -- it takes heroic measures to get *any* actively regulated supply into that ballpark. Indeed, one might be tempted to run a Tbolt off of three batteries, each one charged by a low-noise, high-impedance current source that puts out about .05 CV more than the Tbolt draws. One could even turn the charging off for short periods of minimal noise operation, if the batteries were suitably sized. However, in either case I would be concerned that the drift of one or more of the battery voltages (poor absolute regulation) might introduce another source of XO drift -- but I have not tried it. This has gone overboard. The T-bolt generates digital noise all by itself. It's the OCXO which would benefit most from a clean supply and isolation from the rest of the T-bolt except that temp-sensor. Providing ultra-clean supplies to the digital logic would be overkill, as it would mess it up itself anyway. 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] Thunderbolt Supply
Hi The +12 volts is what you want to keep stable. You would like to keep them all reasonably clean. That's not to hard for -12 since there's next to no current on it. +5 is mostly digital logic, it generates it's own suprs and noise. +12 runs the OCXO and it's internal regulators, it's likely all analog. The issue here isn't as much ultra clean as stable. A well regulated supply on the +12 will give you better performance out of the TBolt. The OCXO does indeed change frequency when the +12 changes. I posted some data a while back. Bob On Feb 15, 2011, at 7:40 AM, Brendan Minish wrote: On Tue, 2011-02-15 at 10:47 +0100, Magnus Danielson wrote: This has gone overboard. The T-bolt generates digital noise all by itself. It's the OCXO which would benefit most from a clean supply and isolation from the rest of the T-bolt except that temp-sensor. Considering the T-bolt has 3 supplies which rail is the one that is most important to keep clean My main interest is the best possible phase noise and spur performance as the 10MHz output is feeding a high quality SDR Providing ultra-clean supplies to the digital logic would be overkill, as it would mess it up itself anyway. I guess what I am wondering, considering I already have a very low noise, stable, battery backed 12V (13.8V really) system in the shack can I use that along with a small dual rail DC-DC converter and still get very good performance -- 73 Brendan EI6IZ ___ 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] Thunderbolt Supply
It seems my mail server was a little overzealous in declaring a message spam, for which I apologize, and will try a resend. On Tue, February 15, 2011 7:40 am, Brendan Minish wrote: I guess what I am wondering, considering I already have a very low noise, stable, battery backed 12V (13.8V really) system in the shack can I use that along with a small dual rail DC-DC converter and still get very good performance I use one of these http://www.cd4power.com/data/power/twr20wa-series.pdf, but I have no idea how noisy it really is. For the moment it meets my needs, even if it is a little pricey. Ralph ___ 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] Thunderbolt Supply
Hi The only way I have found to really take care of the spam trigger issue is to put in a rule that triggers based on it being a mailing list. If you subscribe to a lot of lists, that can be a pain. There is also a school of thought that bouncing spam is no longer a good idea. Lots of long drawn out arguments on both sides of that question. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Ralph Smith Sent: Tuesday, February 15, 2011 10:21 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Thunderbolt Supply It seems my mail server was a little overzealous in declaring a message spam, for which I apologize, and will try a resend. On Tue, February 15, 2011 7:40 am, Brendan Minish wrote: I guess what I am wondering, considering I already have a very low noise, stable, battery backed 12V (13.8V really) system in the shack can I use that along with a small dual rail DC-DC converter and still get very good performance I use one of these http://www.cd4power.com/data/power/twr20wa-series.pdf, but I have no idea how noisy it really is. For the moment it meets my needs, even if it is a little pricey. Ralph ___ 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] Thunderbolt Supply
This has gone overboard. As a sailor I'm careful about using that phrase. Thanks for all the suggestions and information. I;m now back to my original plan to use the Power-One +5V and +/- 15V switching power supply, followed by a pair of 7812/7912 voltage regulators for the + and - 12V. The power supply and Thunderbolt will be mounted in separate enclosures connected with a short(12) cable. I will add ferrite beads on both ends of the wires where they exit and enter the two enclosures, paralleled with 0.1 uF capacitors to ground. The 12 volt regulators will be filtered with 2200uF electrolytic capacitors on each input and 10uF on each output. The 7812/7912 regulators will be mounted on heatsinks mounted on spacers on the back of the enclosure. I am not sure what to do, if anything, to the +5 volt other than adding an inductor of the power-line filter variety in series. If I can find some feed-through capacitors of the threaded variety, I may add them to the back of the Thunderbolt enclosure to replace the original connector. All of this will be mounted on the back of a 1U rack panel. Now, if I could find the correct HP paint code ... -- Flemming LarsenOZ6OI/KB6ADSBerkeley, CA, USA ___ 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] Thunderbolt Supply
has anyone done a setup where the TB is running from a battery when one is using its output. Something like you do with pico amp meters, or I do with the Fluke 845AB null meter ? -pete On Sun, Feb 13, 2011 at 11:29 PM, Flemming Larsen oz...@yahoo.dk wrote: I have a Power-One switching power supply that puts out +/- 15 Volts in addition to +5 Volts. I was planning to add a pair of 7812/7912 voltage regulators to provide the required +/- 12 Volts to the Thunderbolt. I would welcome any suggestions to improvements in this very basic design, including additional filtering, etc. Please post or email. BTW, has anyone considered using one of the many DC-to-DC PSUs that are available for powering mobile PCs from +12 Volts? They appear to be ideal for powering the Thunderbird from almost any DC power source, including a 12 Volt battery. -- Flemming Larsen, OZ6OI/KB6ADS oz...@yahoo.dk ___ 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] Thunderbolt Supply
Hi Can be done with a couple of switchers. I'd do the switcher = LDO trick to clean things up. Bert has a setup running that way. I would not try to run one directly off of a battery. Either you would have a pretty big battery, or it would not last long. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Pete Lancashire Sent: Monday, February 14, 2011 11:51 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Thunderbolt Supply has anyone done a setup where the TB is running from a battery when one is using its output. Something like you do with pico amp meters, or I do with the Fluke 845AB null meter ? -pete On Sun, Feb 13, 2011 at 11:29 PM, Flemming Larsen oz...@yahoo.dk wrote: I have a Power-One switching power supply that puts out +/- 15 Volts in addition to +5 Volts. I was planning to add a pair of 7812/7912 voltage regulators to provide the required +/- 12 Volts to the Thunderbolt. I would welcome any suggestions to improvements in this very basic design, including additional filtering, etc. Please post or email. BTW, has anyone considered using one of the many DC-to-DC PSUs that are available for powering mobile PCs from +12 Volts? They appear to be ideal for powering the Thunderbird from almost any DC power source, including a 12 Volt battery. -- Flemming Larsen, OZ6OI/KB6ADS oz...@yahoo.dk ___ 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] Thunderbolt Supply
I think you should look at the specifications for the noise-rejection capability of those three-terminal regulators. They are simple and inexpensive but not particularly good at noise rejection. Some of the noise from the switcher supply will pass through. Is it enough to cause a real problem? Unknown to me as yet. The power requirements of the Thunderbolt are not the usual ones you see standard supplies designed to meet. I have yet to find a small linear supply that is adequate that does not absolutely dwarf the Thunderbolt itself! Back in The Day, one could find a good assortment of multiple-secondary power transformers that would allow us to build a simple linear supply with the three-terminal regulators; there would no switcher to generate noise. Alas, these transformers are no longer easily available today. I think it can be done with two separate transformers but with the filters, regulators and actual wiring, this adds up to a lot of work! TAPR does offer a 13 vdc input, three-output power supply kit for their software-defined radio kits, but its -12 vdc output comes from a switching dc-dc inverter. That -12 vdc does supply the Thunderbolt OCXO so I have some concern about noise on that power feed. One could get a custom-designed PC board mount transformer and develop a board to supply adequate power. I doubt there is enough interest or purchase volume to justify this, however. So, I'm still looking for a compact linear power supply. I welcome your suggestions! Larry W6FUB On 2/14/2011 10:06 AM, ewkeh...@aol.com wrote: Yes I am doing it with some very low cost switchers off ebay, followed by linear regulators as I mentioned previously. Works great. Bert Kehren ... -- Best wishes, Larry McDavid W6FUB Anaheim, CA (20 miles southeast of Los Angeles, near Disneyland) ___ 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] Thunderbolt Supply
As mentioned before a suitably rated single transformer with a center tapped secondary will suffice if you want to build your own linear psu. I use a 2 amp 25.2 volt center tapped transformer (along with a bridge rectifer, filter caps, 3 terminal regulators, fuse holder etc.) I don't losse any sleep over the 5 volt regulator having to dissipate several watts more than it would if I had a differrent transformer. On Mon Feb 14th, 2011 1:31 PM EST Larry McDavid wrote: I think you should look at the specifications for the noise-rejection capability of those three-terminal regulators. They are simple and inexpensive but not particularly good at noise rejection. Some of the noise from the switcher supply will pass through. Is it enough to cause a real problem? Unknown to me as yet. The power requirements of the Thunderbolt are not the usual ones you see standard supplies designed to meet. I have yet to find a small linear supply that is adequate that does not absolutely dwarf the Thunderbolt itself! Back in The Day, one could find a good assortment of multiple-secondary power transformers that would allow us to build a simple linear supply with the three-terminal regulators; there would no switcher to generate noise. Alas, these transformers are no longer easily available today. I think it can be done with two separate transformers but with the filters, regulators and actual wiring, this adds up to a lot of work! TAPR does offer a 13 vdc input, three-output power supply kit for their software-defined radio kits, but its -12 vdc output comes from a switching dc-dc inverter. That -12 vdc does supply the Thunderbolt OCXO so I have some concern about noise on that power feed. One could get a custom-designed PC board mount transformer and develop a board to supply adequate power. I doubt there is enough interest or purchase volume to justify this, however. So, I'm still looking for a compact linear power supply. I welcome your suggestions! Larry W6FUB On 2/14/2011 10:06 AM, ewkeh...@aol.com wrote: Yes I am doing it with some very low cost switchers off ebay, followed by linear regulators as I mentioned previously. Works great. Bert Kehren ... -- Best wishes, Larry McDavid W6FUB Anaheim, CA (20 miles southeast of Los Angeles, near Disneyland) ___ 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] Thunderbolt Supply
On 14/02/11 19:31, Larry McDavid wrote: I think you should look at the specifications for the noise-rejection capability of those three-terminal regulators. They are simple and inexpensive but not particularly good at noise rejection. Some of the noise from the switcher supply will pass through. Is it enough to cause a real problem? Unknown to me as yet. I think the linear regulator is mainly to handle low frequency damping where as for higher frequencies capacitors and inductors is helpful. They do not exclude themselves, but they may be a cheap and fairly effective in combination. 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] Thunderbolt Supply
Hi, I use a similar setup but used an arangement the uses full wave rectification for the 12V and a single diode half wave rectifier for the 5V so the regulator did not have such high dissipation. Robert G8RPI. --- On Mon, 14/2/11, Mark Spencer mspencer12...@yahoo.ca wrote: From: Mark Spencer mspencer12...@yahoo.ca Subject: Re: [time-nuts] Thunderbolt Supply To: time-nuts@febo.com Date: Monday, 14 February, 2011, 18:55 As mentioned before a suitably rated single transformer with a center tapped secondary will suffice if you want to build your own linear psu. I use a 2 amp 25.2 volt center tapped transformer (along with a bridge rectifer, filter caps, 3 terminal regulators, fuse holder etc.) I don't losse any sleep over the 5 volt regulator having to dissipate several watts more than it would if I had a differrent transformer. On Mon Feb 14th, 2011 1:31 PM EST Larry McDavid wrote: I think you should look at the specifications for the noise-rejection capability of those three-terminal regulators. They are simple and inexpensive but not particularly good at noise rejection. Some of the noise from the switcher supply will pass through. Is it enough to cause a real problem? Unknown to me as yet. The power requirements of the Thunderbolt are not the usual ones you see standard supplies designed to meet. I have yet to find a small linear supply that is adequate that does not absolutely dwarf the Thunderbolt itself! Back in The Day, one could find a good assortment of multiple-secondary power transformers that would allow us to build a simple linear supply with the three-terminal regulators; there would no switcher to generate noise. Alas, these transformers are no longer easily available today. I think it can be done with two separate transformers but with the filters, regulators and actual wiring, this adds up to a lot of work! TAPR does offer a 13 vdc input, three-output power supply kit for their software-defined radio kits, but its -12 vdc output comes from a switching dc-dc inverter. That -12 vdc does supply the Thunderbolt OCXO so I have some concern about noise on that power feed. One could get a custom-designed PC board mount transformer and develop a board to supply adequate power. I doubt there is enough interest or purchase volume to justify this, however. So, I'm still looking for a compact linear power supply. I welcome your suggestions! Larry W6FUB On 2/14/2011 10:06 AM, ewkeh...@aol.com wrote: Yes I am doing it with some very low cost switchers off ebay, followed by linear regulators as I mentioned previously. Works great. Bert Kehren ... -- Best wishes, Larry McDavid W6FUB Anaheim, CA (20 miles southeast of Los Angeles, near Disneyland) ___ 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] Thunderbolt Supply
Hi Ok, since this keeps coming up, here's the full blow by blow of everything you need to do. Nothing left to the imagination :) You have a switcher running into a filter running. The filter feeds into three terminal regulators. The regulators are running into the TBolt. Power to the switcher is from the wall or in some cases from a battery. First issue is inductors for the filter and why you don't want to just use inductors. Finding an inductor that will handle a couple of amps, and have enough inductance to be useful down to 30 Hz is a tough proposition. They are going to be big, heavy, and expensive. A three terminal regulator, properly chosen, will do a great job down at audio. Your switcher takes in 60 Hz, it's got 60 Hz ripple on it's output. You need to get rid of it. No they don't work to hundreds of MHz, but with care you can find ones that do well over the audio range. Next step is the first part of the filter. It needs to take over where your particular three terminal regulator starts to have issues. That could be lower or higher depending on what you use. Finding inductors that will work from a few tens of KHz to a MHz while moving over an amp - much easier than at 30 Hz. The switcher market has us flooded with cheap (like 10 for a dollar) little parts that do that. Three caps, two coils = nice filter. If size is not a big issue, getting low DC drop as well as some inductance is quite doable. Next stop above that - something designed for RF. Might or might not have a chunk of ferrite / powdered iron for a core. If you wind your own, very low cost (maybe a nickel). Likely a double L section, two caps, two coils. With all the coils, you need to look carefully at saturation. A coil that's rated for an amp, but that drops to 10% of it's inductance while doing it is not what you want. That gets you half of the filter. You need to do the same rock and roll with the capacitors. The stuff that works at 10 KHz likely isn't going to do much good at a 200 MHz. Even if they all are ceramics, your dielectrics likely will change between the sections. The net result is a gizmo that's quiet, small, and low dropout. None of the coils will drop much voltage at all. The LDO will be in the sub 1 volt range. If it drops by a volt with the OCXO full on, it should drop back to 0.1 V after warm up. Works fine. Hopefully that clears things up. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Larry McDavid Sent: Monday, February 14, 2011 1:32 PM To: Discussion of precise time and frequency measurement Cc: ewkeh...@aol.com Subject: Re: [time-nuts] Thunderbolt Supply I think you should look at the specifications for the noise-rejection capability of those three-terminal regulators. They are simple and inexpensive but not particularly good at noise rejection. Some of the noise from the switcher supply will pass through. Is it enough to cause a real problem? Unknown to me as yet. The power requirements of the Thunderbolt are not the usual ones you see standard supplies designed to meet. I have yet to find a small linear supply that is adequate that does not absolutely dwarf the Thunderbolt itself! Back in The Day, one could find a good assortment of multiple-secondary power transformers that would allow us to build a simple linear supply with the three-terminal regulators; there would no switcher to generate noise. Alas, these transformers are no longer easily available today. I think it can be done with two separate transformers but with the filters, regulators and actual wiring, this adds up to a lot of work! TAPR does offer a 13 vdc input, three-output power supply kit for their software-defined radio kits, but its -12 vdc output comes from a switching dc-dc inverter. That -12 vdc does supply the Thunderbolt OCXO so I have some concern about noise on that power feed. One could get a custom-designed PC board mount transformer and develop a board to supply adequate power. I doubt there is enough interest or purchase volume to justify this, however. So, I'm still looking for a compact linear power supply. I welcome your suggestions! Larry W6FUB On 2/14/2011 10:06 AM, ewkeh...@aol.com wrote: Yes I am doing it with some very low cost switchers off ebay, followed by linear regulators as I mentioned previously. Works great. Bert Kehren ... -- Best wishes, Larry McDavid W6FUB Anaheim, CA (20 miles southeast of Los Angeles, near Disneyland) ___ 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] Thunderbolt Supply
Has anybody investigated simple L-C (R-L-C) filters rather than linear regulators? The SI-List recently announced a good paper on using ferrite beads. http://www.ipblox.com/papers.html (Currently, it's the top paper. In case somebody finds this in the archives, it's the one marked DesignCon 2011) Page 5 of the slides has the critical graph. A ferrite bead is resistive over a broad range of frequencies. -- 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] Thunderbolt Supply
I use ferrite beads the old ones where the wire goes through a round cylinder five times I get them from Radio Conrad item # 50 21 97 36, 16 cents each and capacitors followed by regulators. The regulators are close to the Tbolt the rest is with the batteries and switchers. Works fine for me and I have looked with my HP3561A and HP 7 series spectrum analyzer and see no problem. More important I do some Phase Noise measurements on PLL's and have much better luck with switchers than 60 Hz keeping noise out. Bert Kehren In a message dated 2/14/2011 3:33:49 P.M. Eastern Standard Time, hmur...@megapathdsl.net writes: Has anybody investigated simple L-C (R-L-C) filters rather than linear regulators? The SI-List recently announced a good paper on using ferrite beads. http://www.ipblox.com/papers.html (Currently, it's the top paper. In case somebody finds this in the archives, it's the one marked DesignCon 2011) Page 5 of the slides has the critical graph. A ferrite bead is resistive over a broad range of frequencies. -- 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 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] Thunderbolt Supply
Bob wrote: A three terminal regulator, properly chosen, will do a great job down at audio. Depends on what you mean by great job. All of the 3T regulators I'm familiar with have at least two orders of magnitude more noise than a well-designed LN analog regulator -- many have much more (especially LDO parts). At the low impedance levels involved, it's challenging to filter it out. Finding inductors that will work from a few tens of KHz to a MHz while moving over an amp - much easier than at 30 Hz. * * * Next stop above that - something designed for RF. * * * The net result is a gizmo that's quiet, small, and low dropout. In both of these ranges, the high current switching transients of the switcher tend to get into everything, including grounds. There are resistive drops (ground loops) plus inductive and capacitive coupling (every wire/trace is an antenna). It takes great care with layout and design to reduce these even to a dull roar, and extraordinary measures to clean up a switcher for precision analog work between DC and several MHz. I'm not saying it can't be done, but it is a lot of work and you have to know exactly what you are doing in an environment where it is very hard to measure what you are trying to eliminate. It almost always involves shielding each module separately, using feedthrough capacitors from module to module, etc. Most of this can be avoided by using only analog regulators. Best regards, Charles ___ 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] Thunderbolt Supply
Hi If all you are doing is running a Thunderbolt, you don't need a supply that's more quiet than most batteries. People get reasonable performance off of straight switcher outputs. Adding simple linear + filtering gets you well into the overkill region on this application. The idea is to stop spending money when you have reached the good enough point. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Charles P. Steinmetz Sent: Monday, February 14, 2011 4:21 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Thunderbolt Supply Bob wrote: A three terminal regulator, properly chosen, will do a great job down at audio. Depends on what you mean by great job. All of the 3T regulators I'm familiar with have at least two orders of magnitude more noise than a well-designed LN analog regulator -- many have much more (especially LDO parts). At the low impedance levels involved, it's challenging to filter it out. Finding inductors that will work from a few tens of KHz to a MHz while moving over an amp - much easier than at 30 Hz. * * * Next stop above that - something designed for RF. * * * The net result is a gizmo that's quiet, small, and low dropout. In both of these ranges, the high current switching transients of the switcher tend to get into everything, including grounds. There are resistive drops (ground loops) plus inductive and capacitive coupling (every wire/trace is an antenna). It takes great care with layout and design to reduce these even to a dull roar, and extraordinary measures to clean up a switcher for precision analog work between DC and several MHz. I'm not saying it can't be done, but it is a lot of work and you have to know exactly what you are doing in an environment where it is very hard to measure what you are trying to eliminate. It almost always involves shielding each module separately, using feedthrough capacitors from module to module, etc. Most of this can be avoided by using only analog regulators. Best regards, Charles ___ 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] Thunderbolt Supply
Hi Ferrite beads are wonderful things. I use them all the time. For this application (main filtering between a TBolt and a switcher) - not a good place to use them. You don't get enough impedance at the switcher frequencies. There are better (and equally cheap) parts available. Bob -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Hal Murray Sent: Monday, February 14, 2011 3:34 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Thunderbolt Supply Has anybody investigated simple L-C (R-L-C) filters rather than linear regulators? The SI-List recently announced a good paper on using ferrite beads. http://www.ipblox.com/papers.html (Currently, it's the top paper. In case somebody finds this in the archives, it's the one marked DesignCon 2011) Page 5 of the slides has the critical graph. A ferrite bead is resistive over a broad range of frequencies. -- 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 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] Thunderbolt Supply
Greetings and my first post from a down-under lurker. A reasonably simple way of producing a clean supply would be the finesse regulator here http://www.wenzel.com/documents/finesse.html I'm not sure how well would clean up the spikey stuff from a switcher though. -- Cheers, Ken vk7...@users.tasmanet.com.au www.vk7krj.com 'It seems hard to sneak a look at God's cards. But that He plays dice and uses telepathic methods is something that I cannot believe for a single moment.' (Einstein's famous quote on Quantum theory) No virus found in this outgoing message. Checked by AVG - www.avg.com Version: 9.0.872 / Virus Database: 271.1.1/3443 - Release Date: 02/14/11 18:34:00 ___ 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] Thunderbolt Supply
This thread makes me appreciated the Symetricom. Just apply 24V and let the internal switcher and regulator do the work. I've designed chips with both bipolar and Pfet pass devices. I really don't like the PNP pass device scheme used in LDOs. There are all sorts of design kludges involved in using a bipolar pass, mostly due to circuitry to keep the BJT out of saturation, and beta boost schemes. The Pfet scheme is much cleaner. With a well designed P-fet pass LDO, the high frequency rejection will be set by a capacitor divider comprised of the CDS cap and the filter cap. That is, at some point the error amp runs out of bandwidth. The manufacturer should have a graph of rejection versus frequency. When you use an inductor, the question is how big is the inductor. Not the physical size, but the effect of the field produced by the inductor. Texas Instruments has a lot of LDOs with integral pfets. ___ 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] Thunderbolt Supply
Bob wrote: If all you are doing is running a Thunderbolt, you don't need a supply that's more quiet than most batteries. Most batteries are *very* quiet -- it takes heroic measures to get *any* actively regulated supply into that ballpark. Indeed, one might be tempted to run a Tbolt off of three batteries, each one charged by a low-noise, high-impedance current source that puts out about .05 CV more than the Tbolt draws. One could even turn the charging off for short periods of minimal noise operation, if the batteries were suitably sized. However, in either case I would be concerned that the drift of one or more of the battery voltages (poor absolute regulation) might introduce another source of XO drift -- but I have not tried it. The idea is to stop spending money when you have reached the good enough point. I quite agree with you on this point (maybe I'd say when you are clearly past the point where other errors dominate the performance envelope). However: People get reasonable performance off of straight switcher outputs. Adding simple linear + filtering gets you well into the overkill region on this application. I'm not sure we know for certain how quiet is good enough for a Tbolt, or where the overkill region is -- particularly when the residual noise contains impulse hash from a switching regulator. I presume most time nuts would consider a 5 dB improvement in phase noise worthwhile for the relatively low cost/effort of using a good linear supply, if that level of improvement can be attained. The only systematic study I've seen is what tvb has on his web site, and it does not include data from a switching supply with external post-regulation and/or post-filtering. Best regards, Charles ___ 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] Thunderbolt Supply
Dear Bert and all, maybe I missed it, but how can a linear regulator filter out transients from a switched PSU? The cited LT1764A has less than 30dB Suppression at 100 kHz getting worse for higher frequencies.Even the famous 7805 had only 50 dB suppression. For going to a real clean PSU, I would expect some old-school filtering and screening should be fine.. or am I wrong? A classic 50/60 Hz all linear PSU has a bad efficiency, but very little high frequency spurs to care about. For my current project (GPSDO with double oven HP10811), I will only use those.. even the classic LED 7-segment display I am planning to use will not use multiplexed mode but quasi-static (1 Hz update rate only). Regards, Achim ___ 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] Thunderbolt Supply
Achim of course I am using Filters, among others the wide band inductors Radio Conrad offers. Contact me direct and I will send you sketches of what I do, including GPSDO with 10811. Where are you located? Bert In a message dated 2/13/2011 8:44:56 A.M. Eastern Standard Time, avoll...@physik.uzh.ch writes: Dear Bert and all, maybe I missed it, but how can a linear regulator filter out transients from a switched PSU? The cited LT1764A has less than 30dB Suppression at 100 kHz getting worse for higher frequencies.Even the famous 7805 had only 50 dB suppression. For going to a real clean PSU, I would expect some old-school filtering and screening should be fine.. or am I wrong? A classic 50/60 Hz all linear PSU has a bad efficiency, but very little high frequency spurs to care about. For my current project (GPSDO with double oven HP10811), I will only use those.. even the classic LED 7-segment display I am planning to use will not use multiplexed mode but quasi-static (1 Hz update rate only). Regards, Achim ___ 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] Thunderbolt Supply
I have a Power-One switching power supply that puts out +/- 15 Volts in addition to +5 Volts. I was planning to add a pair of 7812/7912 voltage regulators to provide the required +/- 12 Volts to the Thunderbolt. I would welcome any suggestions to improvements in this very basic design, including additional filtering, etc. Please post or email. BTW, has anyone considered using one of the many DC-to-DC PSUs that are available for powering mobile PCs from +12 Volts? They appear to be ideal for powering the Thunderbird from almost any DC power source, including a 12 Volt battery. -- Flemming Larsen, OZ6OI/KB6ADS oz...@yahoo.dk ___ 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] Thunderbolt Supply
That is basically what I do. Bert Kehren In a message dated 2/11/2011 11:44:56 P.M. Eastern Standard Time, namic...@gmail.com writes: One approach for the Tbolt is to use a low dropout low noise linear regulator (I used a LT1764 set to 11.5 volts) for the 12 volt input (it is within spec) and a 5V switcher (Recom R-785.0-1.0) for the 5v. For the minus 12v I used a ICL7662, these are rare, so a cmos gate oscillator and diode pump negative generator could be used. I am told the -12V is quite uncritical. The whole lot runs across a 12V lead acid accumulator which delivers about 300mA to run it when the power fails. The battery is floated at 14.0 volts with a linear regulator from a mains transformer power supply. A 20 AH battery gives more than 2 days backup. As the 12Volt is the sensitive input, the linear regulator should keep the noise down. The whole setup is designed to use minimum power. cheers, Neville Michie On 11/02/2011, at 10:16 AM, Larry McDavid wrote: Greetings! I am a new member of the mail list. I've been using a HP Z3801A GPS-steered standard but have just acquired a Trimble Thunderbolt GPS Disciplined Clock. I'm seeking a recommendation for a power supply for this Thunderbolt receiver. There is much discussion about noise from some switching supplies and the effect on phase noise of the 10 MHz output. The Thunderbolt manual specifies the following supply and loads: +12 vdc 750 mA + 5 vdc 400 mA -12 vdc 10 mA This combination is somewhat unusual in that the highest current is on the 12 volt output rather than the 5 volt output. I'm asking if list members have a favorite power supply for this unit, why and where I can obtain one. -- Best wishes, Larry McDavid W6FUB Anaheim, CA (20 miles southeast of Los Angeles, near Disneyland) ___ 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] Thunderbolt Supply
On Feb 11, 2011, at 9:44 PM, Neville Michie wrote: [...]For the minus 12v I used a ICL7662, these are rare, so a cmos gate oscillator and diode pump negative generator could be used. I am told the -12V is quite uncritical.[...] Thanks for the thoughts. I'm thinking about redoing the power supplies for my T-bolts. So, your comments are helpful. May I ask where is the ICL7662 rare? Digikey has over 20K in various forms. I've also heard that the 5V supply is not noise critical. For your minimum power goal, I imagine that's why you used a switcher rather than lose up to 0.4A x 7V (2.8W) using a linear 5V regular off the +12V line. Kevin ___ 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] Thunderbolt Supply
Kevin Rosenberg wrote: On Feb 11, 2011, at 9:44 PM, Neville Michie wrote: [...]For the minus 12v I used a ICL7662, these are rare, so a cmos gate oscillator and diode pump negative generator could be used. I am told the -12V is quite uncritical.[...] Thanks for the thoughts. I'm thinking about redoing the power supplies for my T-bolts. So, your comments are helpful. May I ask where is the ICL7662 rare? Digikey has over 20K in various forms. I've also heard that the 5V supply is not noise critical. For your minimum power goal, I imagine that's why you used a switcher rather than lose up to 0.4A x 7V (2.8W) using a linear 5V regular off the +12V line. Kevin You could look at using a variant of the Cuk switching regulator. These can have relatively low input and output noise before any additional filters that may be added. 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] Thunderbolt Supply
On Feb 10, 2011, at 3:16 PM, Larry McDavid wrote: I'm seeking a recommendation for a power supply for this Thunderbolt receiver. I use an HP 6236B that I bought inexpensively on eBay, after reading about others having good results with that combination. I had to repair it (it had one or two bad caps), but it was still inexpensive after the cost of the components. The TBolt draws more than the supply's rated current on the +12V output during cold start, but neither the TBolt nor the power supply seem to mind, and the operating current settles down into the supply's normal operating range after a few minutes of warm-up. I have the TBolt bolted right on top of the supply (over the coolest corner). This is far from ideal, but the supply's ventilation holes are conveniently spaced to line up with the T-Bolt's mounting holes. I'll improve my setup eventually, when I feel a surge of time-nuttiness coming on. :) Even in its current configuration, it far exceeds my needs for a frequency reference. -- Mark J. Blair, NF6X n...@nf6x.net Web page: http://www.nf6x.net/ GnuPG public key available from my web page. ___ 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] Thunderbolt Supply
On Feb 12, 2011, at 3:12 PM, Bruce Griffiths wrote: Cuk switching regulator Thanks for the tip! Kevin ___ 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] Thunderbolt Supply
On Feb 12, 2011, at 8:16 PM, Mark J. Blair wrote: my setup eventually, when I feel a surge of time-nuttiness coming on. :) Even in its current configuration, it far exceeds my needs for a frequency reference. Exceeding your needs? Doesn't seen like that surge of time-nuttiness has hit yet ;) Kevin ___ 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] Thunderbolt Supply
On Feb 12, 2011, at 11:03 PM, Kevin Rosenberg wrote: Exceeding your needs? Doesn't seen like that surge of time-nuttiness has hit yet ;) Don't worry, I'm just pacing myself. :) -- Mark J. Blair, NF6X n...@nf6x.net Web page: http://www.nf6x.net/ GnuPG public key available from my web page. ___ 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] Thunderbolt Supply
From: Tim Tuck t...@skybase.net Subject: Re: [time-nuts] Thunderbolt Supply Hi Larry, I use a linear supply for mine. My supply is actually a headphone amp supply kit from JayCar Electronics here in Australia. Its basically two LM317's and a 7805 for 5v. I changed the resistor that set the output voltage from 15v to 12v and also selected an appropriate toroid transformer to suit. Links here http://www.jaycar.com.au/productView.asp?ID=KC5418CATID=25form=CATSUBCATID=557 http://www.jaycar.com.au/productView.asp?ID=MT2084CATID=19form=CATSUBCATID=539 I dont know if you can get these kits in the US or if JayCar ship internationally, you'd have to ask. I'm sure you could find or build something similar state side :) regards Tim There's a 3-output linear power supply kit at http://www.goldmine-elec-products.com/prodinfo.asp?number=C6895 that appears to be a good supply for the TBolt. Thinking about ordering one to replace the switcher that I got with my TBolt (TAPR buy). Price is $33.10 US plus S/H. All outputs are adjustable from 1V to full output, but if you want finer control, you can replace the pots with fixed resistors and a lower value pot on each output. This kit appears to be complete, with the exception of an enclosure. ... David dgminala at mediacombb dot net ___ 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] Thunderbolt Supply
Hello The Net: Consider the HP-6235A triple power supply for a single T'Bolt. Consider a HP-6236B triple power supply. 0-6V to 2.5A 0 to +/-20V at 0.5A Can drive 2 each T'Bolts, but not optimally at a cold start. After the high cold start current draw, the +12V draw goes down nicely and then this PS can nicely support 2 each T'Bolts. Other have reported these as being quiet power suppklies. Ebay can be your friend. do a search for either model. Stan, W1LE Cape CodFN41sr ZZZz ___ 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] Thunderbolt Supply
On Thu, Feb 10, 2011 at 3:16 PM, Larry McDavid lmcda...@lmceng.com wrote: Greetings! I am a new member of the mail list. I've been using a HP Z3801A GPS-steered standard but have just acquired a Trimble Thunderbolt GPS Disciplined Clock. I'm seeking a recommendation for a power supply for this Thunderbolt receiver. There is much discussion about noise from some switching supplies and the effect on phase noise of the 10 MHz output. The Thunderbolt manual specifies the following supply and loads: +12 vdc 750 mA + 5 vdc 400 mA -12 vdc 10 mA It's very easy to build a linear supply. A 24V center tap transformers, some diodes and caps and then those three terminal regulators -- = Chris Albertson Redondo Beach, California ___ 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] Thunderbolt Supply
One approach for the Tbolt is to use a low dropout low noise linear regulator (I used a LT1764 set to 11.5 volts) for the 12 volt input (it is within spec) and a 5V switcher (Recom R-785.0-1.0) for the 5v. For the minus 12v I used a ICL7662, these are rare, so a cmos gate oscillator and diode pump negative generator could be used. I am told the -12V is quite uncritical. The whole lot runs across a 12V lead acid accumulator which delivers about 300mA to run it when the power fails. The battery is floated at 14.0 volts with a linear regulator from a mains transformer power supply. A 20 AH battery gives more than 2 days backup. As the 12Volt is the sensitive input, the linear regulator should keep the noise down. The whole setup is designed to use minimum power. cheers, Neville Michie On 11/02/2011, at 10:16 AM, Larry McDavid wrote: Greetings! I am a new member of the mail list. I've been using a HP Z3801A GPS-steered standard but have just acquired a Trimble Thunderbolt GPS Disciplined Clock. I'm seeking a recommendation for a power supply for this Thunderbolt receiver. There is much discussion about noise from some switching supplies and the effect on phase noise of the 10 MHz output. The Thunderbolt manual specifies the following supply and loads: +12 vdc 750 mA + 5 vdc 400 mA -12 vdc 10 mA This combination is somewhat unusual in that the highest current is on the 12 volt output rather than the 5 volt output. I'm asking if list members have a favorite power supply for this unit, why and where I can obtain one. -- Best wishes, Larry McDavid W6FUB Anaheim, CA (20 miles southeast of Los Angeles, near Disneyland) ___ 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] Thunderbolt Supply
Larry, I favor a linear regulated supply rather than a switching supply. I had a TBolt die while connected to a switching supply in an environment where there were frequent power outages. The +12 VDC current drops significantly after the OCXO warms up, probably down to about 200 mA or so. Good luck. They are neat little devices. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]On Behalf Of Larry McDavid Sent: Thursday, February 10, 2011 5:17 PM To: Timenuts Subject: [time-nuts] Thunderbolt Supply Greetings! I am a new member of the mail list. I've been using a HP Z3801A GPS-steered standard but have just acquired a Trimble Thunderbolt GPS Disciplined Clock. I'm seeking a recommendation for a power supply for this Thunderbolt receiver. There is much discussion about noise from some switching supplies and the effect on phase noise of the 10 MHz output. The Thunderbolt manual specifies the following supply and loads: +12 vdc 750 mA + 5 vdc 400 mA -12 vdc 10 mA This combination is somewhat unusual in that the highest current is on the 12 volt output rather than the 5 volt output. I'm asking if list members have a favorite power supply for this unit, why and where I can obtain one. -- Best wishes, Larry McDavid W6FUB Anaheim, CA (20 miles southeast of Los Angeles, near Disneyland) ___ 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 message. Checked by AVG - www.avg.com Version: 10.0.1204 / Virus Database: 1435/3434 - Release Date: 02/10/11 ___ 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] Thunderbolt Supply
Certainly, I'd prefer a linear 3-output supply. But, I've not found a suitable one yet, in linear or switching. TAPR offered one in the past but has no more. So, I'm asking for recommendations and where to get one. Larry On 2/10/2011 3:32 PM, J. L. Trantham wrote: I favor a linear regulated supply rather than a switching supply. I had a TBolt die while connected to a switching supply in an environment where there were frequent power outages. ... -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]On Behalf Of Larry McDavid ... I'm seeking a recommendation for a power supply for this Thunderbolt receiver. There is much discussion about noise from some switching supplies and the effect on phase noise of the 10 MHz output. The Thunderbolt manual specifies the following supply and loads: +12 vdc 750 mA + 5 vdc 400 mA -12 vdc 10 mA This combination is somewhat unusual in that the highest current is on the 12 volt output rather than the 5 volt output. I'm asking if list members have a favorite power supply for this unit, why and where I can obtain one. ... -- Best wishes, Larry McDavid W6FUB Anaheim, CA (20 miles southeast of Los Angeles, near Disneyland) ___ 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] Thunderbolt Supply
Hi Larry, I use a linear supply for mine. My supply is actually a headphone amp supply kit from JayCar Electronics here in Australia. Its basically two LM317's and a 7805 for 5v. I changed the resistor that set the output voltage from 15v to 12v and also selected an appropriate toroid transformer to suit. Links here http://www.jaycar.com.au/productView.asp?ID=KC5418CATID=25form=CATSUBCATID=557 http://www.jaycar.com.au/productView.asp?ID=MT2084CATID=19form=CATSUBCATID=539 I dont know if you can get these kits in the US or if JayCar ship internationally, you'd have to ask. I'm sure you could find or build something similar state side :) regards Tim -- VK2XTT :: QF56if :: BMARC :: WIA :: AMSAT-VK :: AMSAT ___ 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] Thunderbolt Supply
Hi I have so many of them that I run them off big lab grade linear supplies. That's not to good for a single unit. The neatest way is to run some low drop out linear regulators off of a switcher. That way you get it all. The tolerances on the supplies are such that an LDO with a hundred mv dropout works with a +/- 12 volt +5 volt switcher. Bob -Original Message- From: Larry McDavid Sent: Thursday, February 10, 2011 6:46 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Thunderbolt Supply Certainly, I'd prefer a linear 3-output supply. But, I've not found a suitable one yet, in linear or switching. TAPR offered one in the past but has no more. So, I'm asking for recommendations and where to get one. Larry On 2/10/2011 3:32 PM, J. L. Trantham wrote: I favor a linear regulated supply rather than a switching supply. I had a TBolt die while connected to a switching supply in an environment where there were frequent power outages. ... -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]On Behalf Of Larry McDavid ... I'm seeking a recommendation for a power supply for this Thunderbolt receiver. There is much discussion about noise from some switching supplies and the effect on phase noise of the 10 MHz output. The Thunderbolt manual specifies the following supply and loads: +12 vdc 750 mA + 5 vdc 400 mA -12 vdc 10 mA This combination is somewhat unusual in that the highest current is on the 12 volt output rather than the 5 volt output. I'm asking if list members have a favorite power supply for this unit, why and where I can obtain one. ... -- Best wishes, Larry McDavid W6FUB Anaheim, CA (20 miles southeast of Los Angeles, near Disneyland) ___ 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] Thunderbolt Supply
Larry-- I use a +12 volt linear supply (an open-frame leftover) with a 7805 for the +5 rail. For -12, I use a 2 watt isolated dc-dc converter (leftover from another project). As others have stated, the +12 rail seems to be the noise sensitive one. 73 bob k6rtm in silicon valley -- Message: 4 Date: Thu, 10 Feb 2011 15:16:55 -0800 From: Larry McDavid lmcda...@lmceng.com Subject: [time-nuts] Thunderbolt Supply To: Timenuts time-nuts@febo.com Message-ID: 4d5471e7.4050...@lmceng.com Content-Type: text/plain; charset=ISO-8859-1; format=flowed Greetings! I am a new member of the mail list. I've been using a HP Z3801A GPS-steered standard but have just acquired a Trimble Thunderbolt GPS Disciplined Clock. I'm seeking a recommendation for a power supply for this Thunderbolt receiver. There is much discussion about noise from some switching supplies and the effect on phase noise of the 10 MHz output. The Thunderbolt manual specifies the following supply and loads: +12 vdc 750 mA + 5 vdc 400 mA -12 vdc 10 mA This combination is somewhat unusual in that the highest current is on the 12 volt output rather than the 5 volt output. I'm asking if list members have a favorite power supply for this unit, why and where I can obtain one. -- Best wishes, Larry McDavid W6FUB Anaheim, CA (20 miles southeast of Los Angeles, near Disneyland) ___ 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] Thunderbolt Supply
I use a 16 Volt Laptop power supply followed by Low Noise LT1764A linear regulator for +12 and a 7805 for the logic. If you want to splurge use a LT1764A also for the +5.. To generate the -12V a Microchip TC962 followed by a 79L12 does a nice job. The +5 and -12 are not that critical. That is a reliable and good low noise supply. I personally have added eight NMH cells for backup and that adds extra circuits but I first started with the basic circuit mentioned above. Bert Kehren In a message dated 2/10/2011 8:23:22 P.M. Eastern Standard Time, t...@skybase.net writes: Hi Larry, I use a linear supply for mine. My supply is actually a headphone amp supply kit from JayCar Electronics here in Australia. Its basically two LM317's and a 7805 for 5v. I changed the resistor that set the output voltage from 15v to 12v and also selected an appropriate toroid transformer to suit. Links here http://www.jaycar.com.au/productView.asp?ID=KC5418CATID=25form=CATSUBCATI D=557 http://www.jaycar.com.au/productView.asp?ID=MT2084CATID=19form=CATSUBCATI D=539 I dont know if you can get these kits in the US or if JayCar ship internationally, you'd have to ask. I'm sure you could find or build something similar state side :) regards Tim -- VK2XTT :: QF56if :: BMARC :: WIA :: AMSAT-VK :: AMSAT ___ 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] Thunderbolt Supply
I use a Heathkit IP-2718. It only goes to 500 mA on the +12 supply but when the TBolt is turned on, the current goes off scale for a few minutes, the voltage drops about a volt or half volt, but then all comes back on scale as the OCXO warms up. I think I built one years ago but I found several of these on the 'e' site for only a few bucks. However, a power supply for the TBolt should be very easy to build. My ultimate plan was to buid a box that included 110 VAC and +12 VDC supply that would supply all three voltages. Should be fairly easy to do with a 555 as an oscillator to drive a voltage doubler to make the -12 VDC supply capable of low current. Joe -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Larry McDavid Sent: Thursday, February 10, 2011 5:46 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Thunderbolt Supply Certainly, I'd prefer a linear 3-output supply. But, I've not found a suitable one yet, in linear or switching. TAPR offered one in the past but has no more. So, I'm asking for recommendations and where to get one. Larry On 2/10/2011 3:32 PM, J. L. Trantham wrote: I favor a linear regulated supply rather than a switching supply. I had a TBolt die while connected to a switching supply in an environment where there were frequent power outages. ... -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]On Behalf Of Larry McDavid ... I'm seeking a recommendation for a power supply for this Thunderbolt receiver. There is much discussion about noise from some switching supplies and the effect on phase noise of the 10 MHz output. The Thunderbolt manual specifies the following supply and loads: +12 vdc 750 mA + 5 vdc 400 mA -12 vdc 10 mA This combination is somewhat unusual in that the highest current is on the 12 volt output rather than the 5 volt output. I'm asking if list members have a favorite power supply for this unit, why and where I can obtain one. ... -- Best wishes, Larry McDavid W6FUB Anaheim, CA (20 miles southeast of Los Angeles, near Disneyland) ___ 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] Thunderbolt Supply
That's odd. I just went to the TAPR.org web site and can still seem to order an LPU kit for around $43 US. I'm using a TAPR/OpenHPSDR LPU to run two Thunderbolts. The LPU is operating on 13.6 volts off the house battery. The -12 volts is switching, the other two voltages are linear. I used to run Thunderbolts off an HP fiber optic multiplexer power supply, but those are probably not too common. Mike - AA8K On 02/10/2011 06:46 PM, Larry McDavid wrote: Certainly, I'd prefer a linear 3-output supply. But, I've not found a suitable one yet, in linear or switching. TAPR offered one in the past but has no more. So, I'm asking for recommendations and where to get one. Larry ___ 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.
