Re: [time-nuts] HP 5065A super
On Thu, 22 Feb 2018 07:00:54 -0500 ew via time-nuts wrote: > Now a step by step work over, including HP mods for later units like > replacing the 74196’s in the synthesizer module with 74LS196. May have been > end of life of the 74196. With some slight change of the circuit, you should be able to replace the 74196 by an 74163 which is available as LVC and thus should be around for the next 10-20 years at least. > Now to the purpose of this post. The A9 module is after 88 a significant > change and Corby sees an improvement against his Maser. We are doing a board > and maybe some other will be interested. What does the A9 module do, for those of us who have not learned the inner workings of the 5065 by heart? "Integrator Assembly" doesn't say too much > Here are the issues > A is the LT1793 the best choice the time constant is 0.05 seconds with a > 10 K resistor and 5 uF Capacitor What are your constraints? For every single parameter, there is an opamp that beats the LT1793. Do you just want to replace the opamp on A9 or build a new A9 from scratch? If you can live with a power supply <12V, then I'd go for the LTC6240HV. > B should we add resistors and decoupling on the + - 15 volt op amp supplies Depends on the noise of the power supply. My experience is, that resistors in the power path causes more trouble than not having them. Though, I highly suspect those were mostly caused by improper design. If you have problem with noise on the power supply, I would rather suggest to use some low noise LDOs instead. The TPS7Axx family from TI has quite a few offerings of suitable LDOs. They are not on par with the LT3042, but they beat anything you will have in 5065. And they are easier to solder :-) > C Gold plating the edge connecter, does any one know a reasonable source, > or is doing it at home an option and if yes, how best way to do so. There are gold plating solutions available, if you want to do it at home. Though I would suggest to choose a PCB manufacturer that offers it. In europe, i'd recommend Eurocircuits, but i'm pretty sure you have a similarly cheap shop in the US. There are probably some shops in China that offer that as well. Mind you, gold plating will increase the PCB cost considerably, as it's a non-standard process. Not to mention that you need hard gold for connector contacts, which is different from the standard gold plating you will get as surface finish. Attila Kinali -- It is upon moral qualities that a society is ultimately founded. All the prosperity and technological sophistication in the world is of no use without that foundation. -- Miss Matheson, The Diamond Age, Neil Stephenson ___ 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] HP 5065A super
Ais the LT1793 the best choice the time constant is 0.05 seconds with a 10
K resistor and 5 uF Capacitor
Bshould we add resistors and decoupling on the + - 15 volt op amp supplies
CGold plating the edge connecter, does any one know a reasonable source,
or is doing it at home an option and if yes, how best way to do so.
A. The 1793 is a good choice. You should look at the LT1012 also. The
headlines on the 1793 datasheet suggest it is significantly quieter than
the 1012. HOWEVER: you are particularly interested in frequencies well
below 10Hz, and due to an extremely low 1/f noise corner, the 1012 is
actually 5x quieter than the 1793 between 0.1 and 10 Hz (0.5uV for the
1012 p-p vs. 2.4uV p-p for the 1793). The 1012 can also be
overcompensated, which could be a significant advantage in this
application. [Note that the 1793 has lower input current noise than the
1012, but that is irrelevant in the HP circuit because of the relatively
low impedances at the op-amp inputs. Because of that, the input voltage
noise dominates the total noise.]
B. If you do this, the decoupling has to be good down through at least
milliHz, maybe even microHz. That would require capacitors in the 1F
range with suitable decoupling resistors (100 ohms or below). The op
amp is fed by dedicated +/- regulators, so you'll get the best result by
just using the lowest-noise regulators available. That means the LT3042
for V+. You will have to pore through datasheets to find the
lowest-noise negative regulator available today (as above, paying
particular attention to the noise specs below 1Hz).
C. You normally just tell the board house to plate the edge fingers.
It is not outrageously expensive. OR, here is another, heretical
suggestion: I have designed a number of plug-in daughterboards using
ENIG finish on the whole board, including the edge fingers. *NOTE* this
is an "off-label" use of ENIG finish. The board house I used for the
first batch of ENIG-plated fingers (ITEAD Studio) gave me very robust
plating, so I have continued to use them for boards with ENIG-plated
edge fingers.
I tested a number of the cards over more than 100 insertion-removal
cycles, and viewed under magnification there was very little wear and
absolutely no nickel or copper showing ("ENIG" stands for "electroless
nickel immersion gold," meaning the copper is coated first with nickle
and then with gold. The boards I've tested have not worn through the
gold even after >100 insertion-removal cycles -- way, way more than any
plug-in board is likely ever to see.)
*NB:* ENIG plating varies widely from one board house to another, and
very likely varies somewhat from one batch to another at any particular
board house, so YMMV!!! I've done a dozen or so projects with
ENIG-plated fingers using ITEAD Studio, and have been very pleased with
the results each time.
Charles
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Re: [time-nuts] HP 5065A super
Attached the schematic of the A9 my file of the picture is to large it is the integrator. I just gave Corby my extra A12 RVFR that at one time I was going to do something along the way you suggested but age and the number of projects on our list have ought up with reality. Remember when you visited us you got an idea of what we are working on and what has been completed.LED Laser pumping was on our list, we have some ideas and have kicked them around off list. Decided to focus on 5065A On a related subject long term tests on my HP 5061B with the new tube show better than 1E-13 my plan is to discipline the 5065A with it using the 600 second Wenzel circuit. Laying out a new board and have Corby compare it against his Maser. We have a temperature and pressure board for FRK and M100 but I do not think it will be needed with 600 seconds. Bert Kehren In a message dated 2/22/2018 8:55:22 AM Eastern Standard Time, att...@kinali.ch writes: On Thu, 22 Feb 2018 07:00:54 -0500 ew via time-nuts wrote: > Now a step by step work over, including HP mods for later units like > replacing the 74196’s in the synthesizer module with 74LS196. May have been > end of life of the 74196. With some slight change of the circuit, you should be able to replace the 74196 by an 74163 which is available as LVC and thus should be around for the next 10-20 years at least. > Now to the purpose of this post. The A9 module is after 88 a significant > change and Corby sees an improvement against his Maser. We are doing a board > and maybe some other will be interested. What does the A9 module do, for those of us who have not learned the inner workings of the 5065 by heart? "Integrator Assembly" doesn't say too much > Here are the issues > A is the LT1793 the best choice the time constant is 0.05 seconds with a > 10 K resistor and 5 uF Capacitor What are your constraints? For every single parameter, there is an opamp that beats the LT1793. Do you just want to replace the opamp on A9 or build a new A9 from scratch? If you can live with a power supply <12V, then I'd go for the LTC6240HV. > B should we add resistors and decoupling on the + - 15 volt op amp supplies Depends on the noise of the power supply. My experience is, that resistors in the power path causes more trouble than not having them. Though, I highly suspect those were mostly caused by improper design. If you have problem with noise on the power supply, I would rather suggest to use some low noise LDOs instead. The TPS7Axx family from TI has quite a few offerings of suitable LDOs. They are not on par with the LT3042, but they beat anything you will have in 5065. And they are easier to solder :-) > C Gold plating the edge connecter, does any one know a reasonable source, > or is doing it at home an option and if yes, how best way to do so. There are gold plating solutions available, if you want to do it at home. Though I would suggest to choose a PCB manufacturer that offers it. In europe, i'd recommend Eurocircuits, but i'm pretty sure you have a similarly cheap shop in the US. There are probably some shops in China that offer that as well. Mind you, gold plating will increase the PCB cost considerably, as it's a non-standard process. Not to mention that you need hard gold for connector contacts, which is different from the standard gold plating you will get as surface finish. Attila Kinali -- It is upon moral qualities that a society is ultimately founded. All the prosperity and technological sophistication in the world is of no use without that foundation. -- Miss Matheson, The Diamond Age, Neil Stephenson ___ 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] HP 5065A super
Hi
The control loop (of which A9 is a part) ultimately locks the OCXO in the 5065
to the Rb
transition. Gain in the control loop suppresses the noise of the OCXO, making
it’s ADEV
better than it would have been stand alone.
Ok so far? Bob’s not off the tracks (yet)?
The various processes that create ADEV (or whatever you want to call it) on the
OCXO
could be translated back to an “equivalent EFC noise” number at various
frequencies.
More or less, assume an ideal OCXO and blame all the problems on some little
noise
source in series with the EFC line. Very much like blaming all the noise in an
op amp on
the input stage.
Still ok (if a bit unconventional) ?
At this point one should be able to sum the magic EFC noise with op amp noise
or whatever
else you are worried about and compare their magnitudes. If one is 1/100th of
the other
then maybe it’s not the thing to worry about. Yes, you could carry it on
through the various
control loop equations and get things even more correct.
No, I haven’t done all of this, but it seems to be a way to come up with a
fairly detailed answer
to “what’s good enough” in the control loop,
Bob
> On Feb 22, 2018, at 9:04 AM, Charles Steinmetz wrote:
>
>> Ais the LT1793 the best choice the time constant is 0.05 seconds with a
>> 10 K resistor and 5 uF Capacitor
>> Bshould we add resistors and decoupling on the + - 15 volt op amp
>> supplies
>> CGold plating the edge connecter, does any one know a reasonable
>> source, or is doing it at home an option and if yes, how best way to do so.
>
> A. The 1793 is a good choice. You should look at the LT1012 also. The
> headlines on the 1793 datasheet suggest it is significantly quieter than the
> 1012. HOWEVER: you are particularly interested in frequencies well below
> 10Hz, and due to an extremely low 1/f noise corner, the 1012 is actually 5x
> quieter than the 1793 between 0.1 and 10 Hz (0.5uV for the 1012 p-p vs. 2.4uV
> p-p for the 1793). The 1012 can also be overcompensated, which could be a
> significant advantage in this application. [Note that the 1793 has lower
> input current noise than the 1012, but that is irrelevant in the HP circuit
> because of the relatively low impedances at the op-amp inputs. Because of
> that, the input voltage noise dominates the total noise.]
>
> B. If you do this, the decoupling has to be good down through at least
> milliHz, maybe even microHz. That would require capacitors in the 1F range
> with suitable decoupling resistors (100 ohms or below). The op amp is fed by
> dedicated +/- regulators, so you'll get the best result by just using the
> lowest-noise regulators available. That means the LT3042 for V+. You will
> have to pore through datasheets to find the lowest-noise negative regulator
> available today (as above, paying particular attention to the noise specs
> below 1Hz).
>
> C. You normally just tell the board house to plate the edge fingers. It is
> not outrageously expensive. OR, here is another, heretical suggestion: I
> have designed a number of plug-in daughterboards using ENIG finish on the
> whole board, including the edge fingers. *NOTE* this is an "off-label" use
> of ENIG finish. The board house I used for the first batch of ENIG-plated
> fingers (ITEAD Studio) gave me very robust plating, so I have continued to
> use them for boards with ENIG-plated edge fingers.
>
> I tested a number of the cards over more than 100 insertion-removal cycles,
> and viewed under magnification there was very little wear and absolutely no
> nickel or copper showing ("ENIG" stands for "electroless nickel immersion
> gold," meaning the copper is coated first with nickle and then with gold.
> The boards I've tested have not worn through the gold even after >100
> insertion-removal cycles -- way, way more than any plug-in board is likely
> ever to see.)
>
> *NB:* ENIG plating varies widely from one board house to another, and very
> likely varies somewhat from one batch to another at any particular board
> house, so YMMV!!! I've done a dozen or so projects with ENIG-plated fingers
> using ITEAD Studio, and have been very pleased with the results each time.
>
> Charles
>
>
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> time-nuts mailing list -- time-nuts@febo.com
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Re: [time-nuts] HP 5065A super
On Thu, 22 Feb 2018 09:24:53 -0500 ew via time-nuts wrote: > Attached the schematic of the A9 my file of the picture is to large it is the > integrator. Ah.. this looks significantly different than my 5065 service manual shows. So, I guess you want to build a new board that replaces this? Then i would go for the LTC6240HV with a +/-5V power supply. I agree with Charles that you want to have low noise power supplies, though I think using a much cheaper and easier to solder TPS7A49 together with an TPS7A3001 should be more than enough, considering that the LTC6240HV has a PSRR of >80dB. If you need more than +/-5V range for the EFC, I'd add an LTC2057 or LT6018 as amplifier stage after the integrator, powered from +/-15V. An alternative design would be to use a discrete JFET/MOSFET input stage together with an LT6018. But you'd need to select your FET carefully, as it then would limit your 1/f noise and determine your leakage current. Attila Kinali -- It is upon moral qualities that a society is ultimately founded. All the prosperity and technological sophistication in the world is of no use without that foundation. -- Miss Matheson, The Diamond Age, Neil Stephenson ___ 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] HP 5065A super
In message <20180222160256.68d832a88fc2d7da91602...@kinali.ch>, Attila Kinali w rites: >Ah.. this looks significantly different than my 5065 service manual shows. > >So, I guess you want to build a new board that replaces this? > >Then i would go for the LTC6240HV with a +/-5V power supply. Offset voltage (stability) is a, if not the, *very* important parameter for the integrator. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | 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] HP 5065A super
On Thu, 22 Feb 2018 15:33:50 + "Poul-Henning Kamp" wrote: > >Then i would go for the LTC6240HV with a +/-5V power supply. > > Offset voltage (stability) is a, if not the, *very* important > parameter for the integrator. That's another reason to choose the LTC6240 over the LT1793. Beside the smaller 1/f noise (0.55µVpp vs 2.4µVpp), the LTC6240 has a much lower temperature coefficient (0.7µV/°C vs 8µV/°C). The biggest drawback of the LT6240HV is its limited input range of -5V to +3V (for a +/-5V supply). But in an integrator application, this shouldn't be a problem (phase reversal is prevented by the 10k input resistor). Attila Kinali -- It is upon moral qualities that a society is ultimately founded. All the prosperity and technological sophistication in the world is of no use without that foundation. -- Miss Matheson, The Diamond Age, Neil Stephenson ___ 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] HP 5065A super
Here is ENIG fact that is not widely known at the moment but which some might find useful. I could not understand why I get better TDR and insertion loss results from solder-mask covered microstrip transmission lines than from otherwise identical microstrips on the same substrate with soldermask removed and, therefore, covered with ENIG. Gold can't be bad, right? As it turns out, even gold coin has two sides to it. I have found that Shlepnev and McMorrow conducted extensive research and published data, some of which is presented here http://www.simberian.com/Presentations/NickelCharacterizationPresentation_emc2011.pdf In essence, it's not the "G" that is the problem - it is the "N". Immersion Gold layer is not thick enough to contain whole of the skin effect layer (even towards 100GHz) and as signal frequency increases most of the signal ends up travelling through Nickel. As Shlepnev commented "Nickel is the most mysterious metal in electronics." It has significant effect on insertion loss and risetime degradation. "Significant effect" is posh for "bad." Some mass PCB manufacturers have been known to apply ENIG before soldermasking. This causes even more high speed/frequency problems because all of the copper on the outside layers will have Nickel over it - exposed or not. Probably not a problem for majority of ENIG users but could cause a headache or two for unsuspecting. Leo > Date: Thu, 22 Feb 2018 19:02:25 + > From: Mark Sims > > Yes, have the board done with ENIG gold. It typically adds around $15 per > run of boards. I do all my boards with ENIG gold... if for no other reason > than the gold color makes it very easy to determine when your solder paste > properly covers the pads. > > And, as Charles mentioned, the quality and thickness of the gold can vary > depending upon the board house. I have used gojgo.com for a lot of boards. > They do very good, quick work, are well priced, and they seem to have the > best gold finish. > > Hard gold finish is VERY expensive these days. I've been quoted $250+ for > setup charges and per-board costs of over $25. ___ 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] HP 5065A super
In general it's bad practice to gold plate SMT solder pads. The reason is that proper SMT soldering utilizes a very small amount of solder and the gold plating will partially dissolve into the molten solder. Because of the small amount of solder, the percentage of gold will be high enough to embrittle the solder joint, and it will have a high probability of failure. Hand soldering can apply a large enough amount of solder that the percentage of gold in the joint is relatively small and the problem is avoided. -- Tom, N5EG On Thu, Feb 22, 2018 at 12:29 PM, Leo Bodnar wrote: > Here is ENIG fact that is not widely known at the moment but which some > might find useful. > > I could not understand why I get better TDR and insertion loss results > from solder-mask covered microstrip transmission lines than from otherwise > identical microstrips on the same substrate with soldermask removed and, > therefore, covered with ENIG. > > Gold can't be bad, right? As it turns out, even gold coin has two sides to > it. > > I have found that Shlepnev and McMorrow conducted extensive research and > published data, some of which is presented here http://www.simberian.com/ > Presentations/NickelCharacterizationPresentation_emc2011.pdf > > In essence, it's not the "G" that is the problem - it is the "N". > Immersion Gold layer is not thick enough to contain whole of the skin > effect layer (even towards 100GHz) and as signal frequency increases most > of the signal ends up travelling through Nickel. > As Shlepnev commented "Nickel is the most mysterious metal in > electronics." It has significant effect on insertion loss and risetime > degradation. "Significant effect" is posh for "bad." > > Some mass PCB manufacturers have been known to apply ENIG before > soldermasking. This causes even more high speed/frequency problems because > all of the copper on the outside layers will have Nickel over it - exposed > or not. > > Probably not a problem for majority of ENIG users but could cause a > headache or two for unsuspecting. > > Leo > > > Date: Thu, 22 Feb 2018 19:02:25 + > > From: Mark Sims > > > > Yes, have the board done with ENIG gold. It typically adds around $15 > per run of boards. I do all my boards with ENIG gold... if for no other > reason than the gold color makes it very easy to determine when your solder > paste properly covers the pads. > > > > And, as Charles mentioned, the quality and thickness of the gold can > vary depending upon the board house. I have used gojgo.com for a lot of > boards. They do very good, quick work, are well priced, and they seem to > have the best gold finish. > > > > Hard gold finish is VERY expensive these days. I've been quoted $250+ > for setup charges and per-board costs of over $25. > > ___ > 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] HP 5065A super
My reading of IPC J-STD-001F Paragraph 4.5 says that the gold embrittlement issue does not apply to ENIG or ENEPIG. Paragraph 4.5.1 does say other gold shall be removed so there won't be solder embrittlement. Is that still correct? The issue with ENIG and RF is interesting. I have not heard that before but I can find lots of info on the subject. I do not remember seeing ENIG on microstrip boards. Regards, Mark On Thu, Feb 22, 2018 at 2:33 PM, Tom McDermott wrote: > In general it's bad practice to gold plate SMT solder pads. The reason is > that proper SMT soldering utilizes a very small amount of solder and the > gold plating > will partially dissolve into the molten solder. Because of the small amount > of > solder, the percentage of gold will be high enough to embrittle the solder > joint, > and it will have a high probability of failure. > > Hand soldering can apply a large enough amount of solder that the > percentage > of gold in the joint is relatively small and the problem is avoided. > > -- Tom, N5EG > > > > > On Thu, Feb 22, 2018 at 12:29 PM, Leo Bodnar wrote: > > > Here is ENIG fact that is not widely known at the moment but which some > > might find useful. > > > > I could not understand why I get better TDR and insertion loss results > > from solder-mask covered microstrip transmission lines than from > otherwise > > identical microstrips on the same substrate with soldermask removed and, > > therefore, covered with ENIG. > > > > Gold can't be bad, right? As it turns out, even gold coin has two sides > to > > it. > > > > I have found that Shlepnev and McMorrow conducted extensive research and > > published data, some of which is presented here > http://www.simberian.com/ > > Presentations/NickelCharacterizationPresentation_emc2011.pdf > > > > In essence, it's not the "G" that is the problem - it is the "N". > > Immersion Gold layer is not thick enough to contain whole of the skin > > effect layer (even towards 100GHz) and as signal frequency increases most > > of the signal ends up travelling through Nickel. > > As Shlepnev commented "Nickel is the most mysterious metal in > > electronics." It has significant effect on insertion loss and risetime > > degradation. "Significant effect" is posh for "bad." > > > > Some mass PCB manufacturers have been known to apply ENIG before > > soldermasking. This causes even more high speed/frequency problems > because > > all of the copper on the outside layers will have Nickel over it - > exposed > > or not. > > > > Probably not a problem for majority of ENIG users but could cause a > > headache or two for unsuspecting. > > > > Leo > > > > > Date: Thu, 22 Feb 2018 19:02:25 + > > > From: Mark Sims > > > > > > Yes, have the board done with ENIG gold. It typically adds around $15 > > per run of boards. I do all my boards with ENIG gold... if for no other > > reason than the gold color makes it very easy to determine when your > solder > > paste properly covers the pads. > > > > > > And, as Charles mentioned, the quality and thickness of the gold can > > vary depending upon the board house. I have used gojgo.com for a lot of > > boards. They do very good, quick work, are well priced, and they seem > to > > have the best gold finish. > > > > > > Hard gold finish is VERY expensive these days. I've been quoted $250+ > > for setup charges and per-board costs of over $25. > > > > ___ > > 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/m > ailman/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] HP 5065A super
It appears that ENIG gold is extremely thin (2 - 8 microinches), and if so does not cause a solderability problem. -- Tom, N5EG On Thu, Feb 22, 2018 at 3:18 PM, Mark Goldberg wrote: > My reading of IPC J-STD-001F Paragraph 4.5 says that the gold embrittlement > issue does not apply to ENIG or ENEPIG. Paragraph 4.5.1 does say other gold > shall be removed so there won't be solder embrittlement. > > Is that still correct? > > The issue with ENIG and RF is interesting. I have not heard that before but > I can find lots of info on the subject. I do not remember seeing ENIG on > microstrip boards. > > Regards, > > Mark > > > On Thu, Feb 22, 2018 at 2:33 PM, Tom McDermott wrote: > > > In general it's bad practice to gold plate SMT solder pads. The reason > is > > that proper SMT soldering utilizes a very small amount of solder and the > > gold plating > > will partially dissolve into the molten solder. Because of the small > amount > > of > > solder, the percentage of gold will be high enough to embrittle the > solder > > joint, > > and it will have a high probability of failure. > > > > Hand soldering can apply a large enough amount of solder that the > > percentage > > of gold in the joint is relatively small and the problem is avoided. > > > > -- Tom, N5EG > > > > > > > > > > On Thu, Feb 22, 2018 at 12:29 PM, Leo Bodnar wrote: > > > > > Here is ENIG fact that is not widely known at the moment but which some > > > might find useful. > > > > > > I could not understand why I get better TDR and insertion loss results > > > from solder-mask covered microstrip transmission lines than from > > otherwise > > > identical microstrips on the same substrate with soldermask removed > and, > > > therefore, covered with ENIG. > > > > > > Gold can't be bad, right? As it turns out, even gold coin has two sides > > to > > > it. > > > > > > I have found that Shlepnev and McMorrow conducted extensive research > and > > > published data, some of which is presented here > > http://www.simberian.com/ > > > Presentations/NickelCharacterizationPresentation_emc2011.pdf > > > > > > In essence, it's not the "G" that is the problem - it is the "N". > > > Immersion Gold layer is not thick enough to contain whole of the skin > > > effect layer (even towards 100GHz) and as signal frequency increases > most > > > of the signal ends up travelling through Nickel. > > > As Shlepnev commented "Nickel is the most mysterious metal in > > > electronics." It has significant effect on insertion loss and risetime > > > degradation. "Significant effect" is posh for "bad." > > > > > > Some mass PCB manufacturers have been known to apply ENIG before > > > soldermasking. This causes even more high speed/frequency problems > > because > > > all of the copper on the outside layers will have Nickel over it - > > exposed > > > or not. > > > > > > Probably not a problem for majority of ENIG users but could cause a > > > headache or two for unsuspecting. > > > > > > Leo > > > > > > > Date: Thu, 22 Feb 2018 19:02:25 + > > > > From: Mark Sims > > > > > > > > Yes, have the board done with ENIG gold. It typically adds around > $15 > > > per run of boards. I do all my boards with ENIG gold... if for no > other > > > reason than the gold color makes it very easy to determine when your > > solder > > > paste properly covers the pads. > > > > > > > > And, as Charles mentioned, the quality and thickness of the gold can > > > vary depending upon the board house. I have used gojgo.com for a lot > of > > > boards. They do very good, quick work, are well priced, and they seem > > to > > > have the best gold finish. > > > > > > > > Hard gold finish is VERY expensive these days. I've been quoted > $250+ > > > for setup charges and per-board costs of over $25. > > > > > > ___ > > > 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/m > > ailman/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] HP 5065A super
On 2/22/18 12:29 PM, Leo Bodnar wrote: Here is ENIG fact that is not widely known at the moment but which some might find useful. I could not understand why I get better TDR and insertion loss results from solder-mask covered microstrip transmission lines than from otherwise identical microstrips on the same substrate with soldermask removed and, therefore, covered with ENIG. Gold can't be bad, right? As it turns out, even gold coin has two sides to it. I have found that Shlepnev and McMorrow conducted extensive research and published data, some of which is presented here http://www.simberian.com/Presentations/NickelCharacterizationPresentation_emc2011.pdf the ever useful http://www.microwaves101.com/ site has an excellent discussion of this under the "skin effect" heading. ___ 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] HP 5065A super
Hi The same nickel plating effect gets into a lot of things. If you are shopping for very low IMD connectors, nickel plating is out. Things get non-linear (to a very slight degree) when it is present. If -180 db is the goal for those spurs, you might only hit -120 db with the nickel connectors ….. Bob > On Feb 22, 2018, at 9:15 PM, jimlux wrote: > > On 2/22/18 12:29 PM, Leo Bodnar wrote: >> Here is ENIG fact that is not widely known at the moment but which some >> might find useful. >> I could not understand why I get better TDR and insertion loss results from >> solder-mask covered microstrip transmission lines than from otherwise >> identical microstrips on the same substrate with soldermask removed and, >> therefore, covered with ENIG. >> Gold can't be bad, right? As it turns out, even gold coin has two sides to >> it. >> I have found that Shlepnev and McMorrow conducted extensive research and >> published data, some of which is presented here >> http://www.simberian.com/Presentations/NickelCharacterizationPresentation_emc2011.pdf > > the ever useful http://www.microwaves101.com/ site has an excellent > discussion of this under the "skin effect" heading. > > > ___ > 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] HP 5065A super
Keep in mind that soldermask will also change the field distributions around a microstrip line, and will somewhat mitigate the microstrip's dispersive behavior as well. I once worked with some miccrostrip couplers at around 2-4 GHz and found that directivity was significantly improved by adding two layers of thin kapton tape on top of the coupled region, a solution that went into production. I expect that the usual soldermask layer would have about the same effect. Dana On Thu, Feb 22, 2018 at 8:15 PM, jimlux wrote: > On 2/22/18 12:29 PM, Leo Bodnar wrote: > >> Here is ENIG fact that is not widely known at the moment but which some >> might find useful. >> >> I could not understand why I get better TDR and insertion loss results >> from solder-mask covered microstrip transmission lines than from otherwise >> identical microstrips on the same substrate with soldermask removed and, >> therefore, covered with ENIG. >> >> Gold can't be bad, right? As it turns out, even gold coin has two sides >> to it. >> >> I have found that Shlepnev and McMorrow conducted extensive research and >> published data, some of which is presented here >> http://www.simberian.com/Presentations/NickelCharacterizatio >> nPresentation_emc2011.pdf >> >> > the ever useful http://www.microwaves101.com/ site has an excellent > discussion of this under the "skin effect" heading. > > > > ___ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/m > ailman/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] HP 5065A super
Hoi Bob, On Thu, 22 Feb 2018 21:58:09 -0500 Bob kb8tq wrote: > The same nickel plating effect gets into a lot of things. If you are shopping > for very > low IMD connectors, nickel plating is out. Things get non-linear (to a very > slight > degree) when it is present. If -180 db is the goal for those spurs, you might > only > hit -120 db with the nickel connectors ….. Interesting. About what frequency range are you talking? Attila Kinali -- It is upon moral qualities that a society is ultimately founded. All the prosperity and technological sophistication in the world is of no use without that foundation. -- Miss Matheson, The Diamond Age, Neil Stephenson ___ 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] HP 5065A super
Hi > On Feb 23, 2018, at 4:23 PM, Attila Kinali wrote: > > Hoi Bob, > > On Thu, 22 Feb 2018 21:58:09 -0500 > Bob kb8tq wrote: > >> The same nickel plating effect gets into a lot of things. If you are >> shopping for very >> low IMD connectors, nickel plating is out. Things get non-linear (to a very >> slight >> degree) when it is present. If -180 db is the goal for those spurs, you >> might only >> hit -120 db with the nickel connectors ….. > > Interesting. About what frequency range are you talking? UHF up into microwaves. It was part of a lecture back when I was in school … I assume the basic physics hasn’t changed since then :) Bob > > Attila Kinali > > -- > It is upon moral qualities that a society is ultimately founded. All > the prosperity and technological sophistication in the world is of no > use without that foundation. > -- Miss Matheson, The Diamond Age, Neil Stephenson > ___ > 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] HP 5065A super
On Thu, Feb 22, 2018 at 3:29 PM, Leo Bodnar wrote: > Here is ENIG fact that is not widely known at the moment but which some might > find useful. > > I could not understand why I get better TDR and insertion loss results from > solder-mask covered microstrip transmission lines than from otherwise > identical microstrips on the same substrate with soldermask removed and, > therefore, covered with ENIG. > > Gold can't be bad, right? As it turns out, even gold coin has two sides to it. > > I have found that Shlepnev and McMorrow conducted extensive research and > published data, some of which is presented here > http://www.simberian.com/Presentations/NickelCharacterizationPresentation_emc2011.pdf > > In essence, it's not the "G" that is the problem - it is the "N". > Immersion Gold layer is not thick enough to contain whole of the skin effect > layer (even towards 100GHz) and as signal frequency increases most of the > signal ends up travelling through Nickel. > As Shlepnev commented "Nickel is the most mysterious metal in electronics." > It has significant effect on insertion loss and risetime degradation. > "Significant effect" is posh for "bad." It might be the most mysterious, but Zinc gets my vote for "most annoying". See: https://nepp.nasa.gov/whisker/reference/tech_papers/2004-Brusse-Zn-whisker-IT-Pro.pdf I once worked in a datacenter which had such a bad case of zinc whiskers that, when we got bored, we'd turn off the lights and watch the pretty blue arcs as the whiskers would get pulled through power supplies, bridge something which could deliver current and vaporize, making a small snapping noise in the process. The scary part was that you could bang on the side of a crac, wait 30 seconds, and be rewarded with a fireworks show... W > > Some mass PCB manufacturers have been known to apply ENIG before > soldermasking. This causes even more high speed/frequency problems because > all of the copper on the outside layers will have Nickel over it - exposed or > not. > > Probably not a problem for majority of ENIG users but could cause a headache > or two for unsuspecting. > > Leo > >> Date: Thu, 22 Feb 2018 19:02:25 + >> From: Mark Sims >> >> Yes, have the board done with ENIG gold. It typically adds around $15 per >> run of boards. I do all my boards with ENIG gold... if for no other reason >> than the gold color makes it very easy to determine when your solder paste >> properly covers the pads. >> >> And, as Charles mentioned, the quality and thickness of the gold can vary >> depending upon the board house. I have used gojgo.com for a lot of boards. >> They do very good, quick work, are well priced, and they seem to have the >> best gold finish. >> >> Hard gold finish is VERY expensive these days. I've been quoted $250+ for >> setup charges and per-board costs of over $25. > > ___ > 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. -- I don't think the execution is relevant when it was obviously a bad idea in the first place. This is like putting rabid weasels in your pants, and later expressing regret at having chosen those particular rabid weasels and that pair of pants. ---maf ___ 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] HP 5065A super
On 2/23/18 1:33 PM, Bob kb8tq wrote: Hi On Feb 23, 2018, at 4:23 PM, Attila Kinali wrote: Hoi Bob, On Thu, 22 Feb 2018 21:58:09 -0500 Bob kb8tq wrote: The same nickel plating effect gets into a lot of things. If you are shopping for very low IMD connectors, nickel plating is out. Things get non-linear (to a very slight degree) when it is present. If -180 db is the goal for those spurs, you might only hit -120 db with the nickel connectors ….. Interesting. About what frequency range are you talking? UHF up into microwaves. It was part of a lecture back when I was in school … I assume the basic physics hasn’t changed since then :) Passive intermodulation distortion? What is the physics... hysteresis curves in the magnetization of the nickel is what I would suspect. ___ 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] HP 5065A super
Hi > On Feb 23, 2018, at 6:17 PM, jimlux wrote: > > On 2/23/18 1:33 PM, Bob kb8tq wrote: >> Hi >>> On Feb 23, 2018, at 4:23 PM, Attila Kinali wrote: >>> >>> Hoi Bob, >>> >>> On Thu, 22 Feb 2018 21:58:09 -0500 >>> Bob kb8tq wrote: >>> The same nickel plating effect gets into a lot of things. If you are shopping for very low IMD connectors, nickel plating is out. Things get non-linear (to a very slight degree) when it is present. If -180 db is the goal for those spurs, you might only hit -120 db with the nickel connectors ….. >>> >>> Interesting. About what frequency range are you talking? >> UHF up into microwaves. It was part of a lecture back when I was in school … >> I >> assume the basic physics hasn’t changed since then :) > > > Passive intermodulation distortion? What is the physics... hysteresis curves > in the magnetization of the nickel is what I would suspect. > It turns out that the nickel’s really awful magnetic properties at RF get it into all sorts of problems. More or less, the issue is the non-linear field response in the vicinity of the nickel. You go from “reasonable skin depth” to “don’t go there” in zero distance when you hit the nickel plating. Past that it gets a bit complicated and it was a very long time ago …. Bob > ___ > 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] HP 5065A super
In message <2a6c14a0-823a-4177-aefd-bed8bcea8...@n1k.org>, Bob kb8tq writes: >It turns out that the nickel’s really awful magnetic properties at RF [...] The semiconductor industry has serious problems with electromigration of very tiny copper conductors. A large company in the business spent an awful lot of money failing to get Cobalt to work, before somebody said "But wait, isn't that one of the magnetic elements ?" It now seems to become Wolfram instead. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | 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] HP 5065A super
FRK is possible candidate we are looking at it add filter, reduce time constant Corby did but forgot to reduce filter time constant. 5065A is 0.05 seconds. We have to many projects low on the list Juerg is right now doing the new A9 for Corby If any body wants to seriously get involved contact me off list Bert Kehren In a message dated 2/23/2018 8:28:23 PM Eastern Standard Time, time-nuts@febo.com writes: ant List, I've been following the ongoing mod process for the HP 5065A super on the list. Two questions: 1. Are any of these upgrades applicable to the Lucnet and other Rb units? 2. Are there any other Rb units available (that don't cost you your first born child IF they can be found) that could be fine tuned as Corby is doing? Regards, Perrier ___ 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.
