AoE x-Chapters - 1x.1 Wire-&-Connectors

[Phil Hobbs]

On 8/6/19 4:54 AM, whit3rd wrote:

On Monday, August 5, 2019 at 6:58:20 PM UTC-7, Phil Hobbs wrote:
On 8/5/19 8:50 PM, George Herold wrote:
On Monday, August 5, 2019 at 2:23:12 PM UTC-4, Phil Hobbs wrote:

One other thing about Teflon wire is that it's a royal pain to strip
using dikes.

I generally use Xcelite flush cutters, which are far better than the
usual axe-blade dikes. I ...
just want insulation to do as it's damn well told, and Teflon doesn't,
in so many, many ways.

Did a few fine-wire end preps, with 40 gage gold in PTFE jacket.
Scalpel, microscope, patience. And some extra wire length, just in case.

Wise. When my customers want me to build something with some expensive
part ($700 for a 488-nm laser diode, for instance), I always tell them I
want one to use and one to blow up.

Cheers

Phil Hobbs
(Who almost never blows them up, but the odd time....)

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Phil Hobbs]

On 8/5/19 11:02 PM, Tim Williams wrote:

"Phil Hobbs" <pcdhSpamMeSenseless@electrooptical.net> wrote in message
news:qian03$9nf$2@gioia.aioe.org...

Star grounds in fast mixed signal systems, now _that's_ a disaster.


The worst part about it is, star grounding _is_ excellent, but it has to
be the correct topology.

Sawing up grounds, ain't it.  Routing signals between spokes, ain't it.

Placing signal grounds together, routing signals with ground, in a star
fashion, is the way to be.

Classic example, the ground loop currents in an SMPS section create a
voltage drop across the area; so, route the input and output terminals
off to a single side (as opposed to straight across), where they can
exit over the same common ground area.  Place your filter here.  CM
noise is *gone*.

But that's not a star ground!

HoJo is right that ground currents are important--he's just wrong about
how they work and what to do about it.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Phil Hobbs]

On 8/6/19 2:29 AM, John Robertson wrote:

On 2019/08/05 1:01 p.m., klaus.kragelund@gmail.com wrote:
On Monday, 5 August 2019 21:52:56 UTC+2, klaus.k...@gmail.com  wrote:
On Monday, 5 August 2019 16:20:18 UTC+2, Winfield Hill  wrote:
Here's a DRAFT copy of x-Chapter 1x.1, which starts
  things off, by dealing with wire and connectors.
  Comments and corrections please.

https://www.dropbox.com/s/kz335xwvl5v8gie/1x.1_Wire-%26-Connectors_DRAFT.pdf?dl=1



Some comments:

For leaded, you can also use Pin in Paste and laser soldering.

Also instead of wave, you can use selective soldering, which is more
controlled than a broad wave

For connectors, fretting corrosion is the real killer.

Use decent amount of gold plating, and use the same plating for both
plug and socket. Otherwise it makes no sense to add gold.

Also, too much gold is not better either. Just a waste of money

For fretting, to avoid it all together, use a bleading current so
that the connection is always "current" driven at at least mA level.
Reduces effects of fretting corrosion dramatically

For connectors, between 2 PCBs, use a floating connection. One PCB
locked, the other able to float. That way mating is secure, and
thermal expansion cycles does not wear out the connection

For the ac resistances, skin effect, maybe mention dowells equation,
mostly used for transformers. Just a couple of layers in a winding
can increase the DC resistance 100 fold

Cheers

Klaus

Avoid SMD connectors, they rip off the traces of the PCB

For high quality connections, use pressfit, which also removes the
leaded wave solder process

For best possible connections use gat tight connections. Press fit,
crimping, splicing, wire wrap


I can't recommend insulation displacement connections - after about ten
to twenty years they start to fail due to (assumption here on my part)
gradual displacement of the insulation leading to the wire strands
losing their stiffness and the connection becomes iffy as the strands
displace.

John  :-#)#

Good IDCs displace the insulation entirely and just grip the wires.
Grip varies fairly widely between types, as judged by how hard you have
to crank the vise to seat them.

Which ones don't you like?

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Phil Hobbs]

On 8/6/19 12:11 AM, John Larkin wrote:

On Mon, 5 Aug 2019 22:02:38 -0500, "Tim Williams"
tiwill@seventransistorlabs.com> wrote:

"Phil Hobbs" <pcdhSpamMeSenseless@electrooptical.net> wrote in message
news:qian03$9nf$2@gioia.aioe.org...

Star grounds in fast mixed signal systems, now _that's_ a disaster.


The worst part about it is, star grounding _is_ excellent, but it has to be
the correct topology.

Sawing up grounds, ain't it. Routing signals between spokes, ain't it.

Placing signal grounds together, routing signals with ground, in a star
fashion, is the way to be.

Classic example, the ground loop currents in an SMPS section create a
voltage drop across the area; so, route the input and output terminals off
to a single side (as opposed to straight across), where they can exit over
the same common ground area. Place your filter here. CM noise is *gone*.

Tim

Signal integrity is easy. PCB layer 2 is solid ground plane. Bolt it,
and grounded connector shells, to the metal box in as many places as
possible.

Cable shields to the box ditto.

Agreed, provided one has good wisdom (and instincts) for component
placement.

Cheers

Phil Hobbs


--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Phil Hobbs]

On 8/5/19 10:56 PM, Tim Williams wrote:

1x.1.4.A: Free resistance?  That sounds useful! ...Ah, may want to add a
note that copper's tempco is _deplorable_, to discourage that creative
use (or, at least, make it understood that your use will have to be a
bit more creative in turn).

Hanging parenthesis in 1x.1.5 (instrumentation cable).

Worth noting that 1x.1.6.A is doing the same thing that's already been
covered: impedance.  Zo goes as the ratio of inductance and capacitance,
Zo = sqrt(L/C).  And if you know the velocity factor, mu_r or e_r, you
know the L and C of the transmission line.  So in the same way that you
can know or look up trace impedances, and their inductance or
capcaitance, at a glance, so too it works for cables.

Or put another way, it seems odd to me, or unfair even, that there's a
subsection on inductance, but not capacitance, or not both in general
(impedance).

May be worth noting that, even though multiconductor cable isn't
intended for transmission line purposes, it still has some impedance;
might be an opportunity to emphasize why it's generally undesirable to
do so (i.e., coupling).

Give or take whatever's referred to the transmission line section
proper, of course (appendix H?).

Footnote 16 -- to be even more precise, it's a boundary condition and
wave problem, like all EM problems, I suppose; in an infinite cylinder
the solutions are not actually exponential, but Bessel functions.  For
this reason, you can get current density going to zero at some depth,
then popping up below there /in the opposite direction/!  (delta is
still the figure of proportion that feeds the Bessel function, so it's
still close enough to exponential for the engineer's hand-wave.)  Not
very useful for cabling, but it's interesting for industrial induction
heating anyway.

Depends on the metal and on the frequency. You can get that sort of
behaviour in free-electron metals in the IR, but not in "normal
conductors" at RF. In the high-conductivity limit the fields inside the
conductor aren't oscillatory with depth but are modified Bessel
functions. If that weren't so, there would be certain wire radii where
the radial field went to zero at the surface, so you wouldn't be able to
satisfy the patching conditions at the boundary unless the field outside
were identically zero.

Likewise, for flat plates, you get interference from the waves
penetrating the front and back sides (if currents are arranged to flow
there; think coplanar waveguide but with copper thickness way higher
than width?), leading to nulls and opposite peaks towards the center.

The pure exponential case is only for a semi-infinite block, of course;
for d >> delta, the geometry doesn't really matter, and we can still use
this figure.  It's just that weird things happen for d ~ delta.

The tails of the fields interact in the middle, which makes the falloff
much slower--the physics is basically the same as frustrated total
internal reflection. I've used that in high-NA microscopy.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Phil Hobbs]

On 8/6/19 4:07 AM, David Nadlinger wrote:

On 05.08.19 1:32 PM, Winfield Hill wrote:
  Here's a DRAFT copy of x-Chapter 1x.1, which starts
  things off, by dealing with wire and connectors.
  Comments and corrections please.

https://www.dropbox.com/s/kz335xwvl5v8gie/1x.1_Wire-%26-Connectors_DRAFT.pdf?dl=1


Regarding that circled capital L in footnote 21: Litzendraht as a German
noun should indeed be uppercase, so the current footnote is correct
(potential disagreements about capitalisation of the loanword in the
body copy notwithstanding).

 — David

Only in German. In English we capitalize only proper nouns or those at
the beginning of sentences.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[John Larkin]

On Tue, 6 Aug 2019 00:32:26 -0500, "Tim Williams"
<tiwill@seventransistorlabs.com> wrote:

"John Larkin" <jjlarkin@highlandtechnology.com> wrote in message
news:cavhkeppudjiempknhs0jb84jpkau3sgo8@4ax.com...
Signal integrity is easy. PCB layer 2 is solid ground plane. Bolt it,
and grounded connector shells, to the metal box in as many places as
possible.

Cable shields to the box ditto.


Not really. Suppose there's a huge noisy inverter in the box. Ground loop
currents once again. Cables simply tied "shields to the box", and PCB
"bolt[ed] ... to the metal box", draws those currents into both. Now your
precision ADCs are all reading trash.

Here's a 12-bit, 250 MHz ADC a couple inches from a multi-output
switching power supply. The 6-diode CW multiplier string is about an
inch away.

https://www.dropbox.com/s/opa02hou39tduiq/ESM_rev_B.jpg?raw=1

Noise is below 1 lsb RMS.

One solid layer 2 plane. Everything is grounded.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[George Herold]

On Tuesday, August 6, 2019 at 3:55:13 AM UTC-4, piglet wrote:

On 06/08/2019 02:58, Phil Hobbs wrote:

I'll be 60 late next month, so a few strippers would be apropos--just
don't tell my wife. Maybe they could jump out of a cake.

I generally use Xcelite flush cutters, which are far better than the
usual axe-blade dikes.  I also have the usual spade lug crimper / bolt
cutter/ wire stripper tools.  I don't like the big clunky strippers that
mechanically sense the insulation and adjust their blades accordingly--I
just want insulation to do as it's damn well told, and Teflon doesn't,
in so many, many ways.


I'll be 60 a few months after you. I already have my strippers! They're
Teledyne thermal and cope fine with Teflon and dialled back with any
other insulation devised.

piglet

Hah! I turn 61 in October. Respect your elders.*

George H.
*In grad school there was this smart Korean student. He'd been in the lab for years
and I was the newcomer post doc, who barely knew anything of the field.
(FIR spectroscopy of semiconductors) But I knew a bunch of electronics and low
temperature techniques. He would dismiss all my suggestions, then he learned
one day that I was a few weeks older than him. Like day and night I was now
his elder to be respected.. it struck me as weird, but totally part of Korean
culture according to the other Korean students at the school.

 

[George Herold]

On Tuesday, August 6, 2019 at 10:16:04 AM UTC-4, John Larkin wrote:

On Tue, 6 Aug 2019 00:32:26 -0500, "Tim Williams"
tiwill@seventransistorlabs.com> wrote:

"John Larkin" <jjlarkin@highlandtechnology.com> wrote in message
news:cavhkeppudjiempknhs0jb84jpkau3sgo8@4ax.com...
Signal integrity is easy. PCB layer 2 is solid ground plane. Bolt it,
and grounded connector shells, to the metal box in as many places as
possible.

Cable shields to the box ditto.


Not really. Suppose there's a huge noisy inverter in the box. Ground loop
currents once again. Cables simply tied "shields to the box", and PCB
"bolt[ed] ... to the metal box", draws those currents into both. Now your
precision ADCs are all reading trash.

Here's a 12-bit, 250 MHz ADC a couple inches from a multi-output
switching power supply. The 6-diode CW multiplier string is about an
inch away.

https://www.dropbox.com/s/opa02hou39tduiq/ESM_rev_B.jpg?raw=1

Noise is below 1 lsb RMS.

One solid layer 2 plane. Everything is grounded.

Sure, but star grounding has a place at low frequency.
I cut my star grounding 'teeth' making a low freq. teaching lockin.
https://www.teachspin.com/signal-processor-lock-in

Where a uV of 'signal' getting into the wrong input would ruin my whole day.

George H.

--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[Don Kuenz]

John Robertson <spam@flippers.com> wrote:

On 2019/08/05 2:19 p.m., klaus.kragelund@gmail.com wrote:
On Monday, 5 August 2019 22:47:20 UTC+2, John Robertson wrote:
On 2019/08/05 5:32 a.m., Winfield Hill wrote:
Here's a DRAFT copy of x-Chapter 1x.1, which starts
things off, by dealing with wire and connectors.
Comments and corrections please.

https://www.dropbox.com/s/kz335xwvl5v8gie/1x.1_Wire-%26-Connectors_DRAFT.pdf?dl=1

On page 17 where you start talking about connectors you state:

“The most unreliable components in any electronic system will be the
following (worst first): 1. Connectors and cables. 2. Switches. 3.
Potentiometers and trimmers.”

My experience with arcade games and monitor (tube and LED/LCD) repairs
would fit electrolytic capacitors between #2 and #3. Or possibly even as
#2...

Is that not your experience too when repairing defective equipment?

Thanks for proving a draft to read, it is informative and I enjoy your
style of humour, which makes for a more readable manual.

Experience from pump industry, electrolytics are number 1 field failure failu
re item, when mechanics is omitted


I guess mechanics is the point here - his first three items are all
mechanical devices. I still find mechanical switches to be somewhat more
reliable than electrolytic caps.

It's my experience with motherboards that electrolytic capacitors rank
as the #1 cause of failure.
In regards to connectors, it recently took me /weeks/ to debug
hookup wire connectors on an audio mixer amplifier. The circuit itself
took less than a day to design and a prototype was up and running by the
end of the second day.
Then, back in late June, an article about the feasibility of using
28 AWG IDC as audio hookup was posted by me. Your follow up inspired me
to use hand twisted hookup wire instead. Easy peasy.
All hell (hum actually) broke loose after everything was initially
crammed into a 4" x 2.8" x 2" Bud box. It took a lot of time and effort
to make the hookup connectors mechanically reliable. The project details
will appear in the near future at my website.

73,

--
Don Kuenz, KB7RPU

 

[Don Kuenz]

boB <boB@k7iq.com> wrote:

On 5 Aug 2019 05:32:08 -0700, Winfield Hill <winfieldhill@yahoo.com
wrote:

Here's a DRAFT copy of x-Chapter 1x.1, which starts
things off, by dealing with wire and connectors.
Comments and corrections please.

https://www.dropbox.com/s/kz335xwvl5v8gie/1x.1_Wire-%26-Connectors_DRAFT.pdf?dl=1



Did you notice the one note in this version ?

"Paul, litzendraht, and litz, all need to be lower case."


Also, since you have some handy tools in the chapter, one useful tool
that we use often is the electric enamled wire stripping tool of which
there are a few out there... Might be worth a picture...

https://www.ebay.com/itm/Pro-DF-6-handheld-Magnet-wire-Stripping-Machine-stripper-Cutter-110v-US-STOCK-/333086834927


https://www.aliexpress.com/item/32749284319.html

https://sanshinetechnology.en.made-in-china.com/product/EKTnzLDCuQcp/China-Handset-Enamel-Wire-Stripping-Machine-SS-SM06-Repalce-ABISOFIX-Stripper-.html

A stripping machine sure seems better for my own health than dipping one
end into a solder pot (IIRC) or a jar of paint remover.

Thank you, 73,

--
Don Kuenz, KB7RPU

 

[John Larkin]

On Tue, 6 Aug 2019 07:46:11 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

On 8/6/19 12:11 AM, John Larkin wrote:
On Mon, 5 Aug 2019 22:02:38 -0500, "Tim Williams"
tiwill@seventransistorlabs.com> wrote:

"Phil Hobbs" <pcdhSpamMeSenseless@electrooptical.net> wrote in message
news:qian03$9nf$2@gioia.aioe.org...

Star grounds in fast mixed signal systems, now _that's_ a disaster.


The worst part about it is, star grounding _is_ excellent, but it has to be
the correct topology.

Sawing up grounds, ain't it. Routing signals between spokes, ain't it.

Placing signal grounds together, routing signals with ground, in a star
fashion, is the way to be.

Classic example, the ground loop currents in an SMPS section create a
voltage drop across the area; so, route the input and output terminals off
to a single side (as opposed to straight across), where they can exit over
the same common ground area. Place your filter here. CM noise is *gone*.

Tim

Signal integrity is easy. PCB layer 2 is solid ground plane. Bolt it,
and grounded connector shells, to the metal box in as many places as
possible.

Cable shields to the box ditto.

Agreed, provided one has good wisdom (and instincts) for component
placement.

Cheers

Phil Hobbs

Exactly. The noise is in the details.

"The first rule is that there are no rules."


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[George Herold]

On Monday, August 5, 2019 at 9:58:20 PM UTC-4, Phil Hobbs wrote:

On 8/5/19 8:50 PM, George Herold wrote:
On Monday, August 5, 2019 at 2:23:12 PM UTC-4, Phil Hobbs wrote:
On 8/5/19 8:32 AM, Winfield Hill wrote:
Here's a DRAFT copy of x-Chapter 1x.1, which starts things off, by
dealing with wire and connectors. Comments and corrections please.

https://www.dropbox.com/s/kz335xwvl5v8gie/1x.1_Wire-%26-Connectors_DRAFT.pdf?dl=1




Wow, an embarrassment of riches today.

One other thing about Teflon wire is that it's a royal pain to strip
using dikes.
Huh, Phil, I've been meaning to ask this for a while... but it
seems to me you need a good pair of dikes, with sharp holes for each
wire size. I've got these "paladin" strippers.. but I think someone
bought them out.
Can I send you some good strippers for your Birthday? :^)

I'll be 60 late next month, so a few strippers would be apropos--just
don't tell my wife. Maybe they could jump out of a cake.

I generally use Xcelite flush cutters, which are far better than the
usual axe-blade dikes. I also have the usual spade lug crimper / bolt
cutter/ wire stripper tools. I don't like the big clunky strippers that
mechanically sense the insulation and adjust their blades accordingly--I
just want insulation to do as it's damn well told, and Teflon doesn't,
in so many, many ways.

Well I've got a pair of these,
https://www.amazon.com/Greenlee-PA1118-GripP-Stripper-Cutter/dp/B0006BHHDQ
(I guess Grennlee bought Paladin tools) If you don't have something like that
then that's what's coming for your B-day. I see Amazon has a deal on two pairs,
(different wire sizes.) I don't think I can make 'em jump out of a cake. :^)

George h.

Cheers

Phil Hobbs



George H.
Irradiated PVC can be stripped in one motion with a pair
of sharp cutters.

Prepreg isn't copper coated--the plating is on the cores. The cores are
pre-cured, but the prepreg flows during lamination.

It's usually best to ask the board house what width to use for a 50-ohm
line. FR-4 varies fairly widely in dielectric constant, and they know
what brand they're using.

PCB propagation is faster on surface levels than inside, because the
effective refractive index is ~sqrt((1+epsilon)/2) = 1.68 vs
sqrt(epsilon) = 2.1.

I'd really like a couple more sentences on FFC/FPC cables. We use them
all over the place, and they're great. The 1-mm ones are much less
likely than the 0.5s to short out if you put them in a bit crooked. The
jumpers you can buy are all made by taking wire and rolling it out flat,
so they can carry lots of current, but if you get them made from plated
Kapton, they are the undisputed champs at getting wires on and off cold
plates.

Twisted pair helps crosstalk if you're really driving and receiving
differentially, i.e. the odd mode, using Ethernet transformers, for
instance. The even mode couples back and forth very easily.

I didn't know about the big-box effect. Cool!

Connector catalogues are full of things that they don't actually stock
but would be happy to make for you if you order 100k pieces. Always
check for ample distributor stock before designing in any part, but
connectors _especially_.


You're _way_ too kind to the Black Magic folks. HoJo is completely up a
pole on the subject of ground currents, among many other things. He had
a video (since pulled down) on an electrostatic demo purporting to show
ground currents following under the traces, but ten seconds calculation
showed that his impedance levels were, like, six orders of magnitude
away from where inductance would make any difference. The "ground
plane" was made up of metal squares affixed to one side of a piece of
glass, with the traces on the other side. The twists and turns of the
"ground current" were governed entirely by corona discharge from the
corners of the squares in the regions of highest E field. Yet he was
giving this cockamamie magnetic explanation. The SNR of the Black Magic
books is no more than 3 dB IMO.

JL and I had a fun go-round here on that some years back--we were
competing to see if we could sell our copies to _somebody_.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Don Kuenz]

Tim Williams <tiwill@seventransistorlabs.com> wrote:

"John Larkin" <jjlarkin@highlandtechnology.com> wrote in message
news:cavhkeppudjiempknhs0jb84jpkau3sgo8@4ax.com...
Signal integrity is easy. PCB layer 2 is solid ground plane. Bolt it,
and grounded connector shells, to the metal box in as many places as
possible.

Cable shields to the box ditto.


Not really. Suppose there's a huge noisy inverter in the box. Ground loop
currents once again. Cables simply tied "shields to the box", and PCB
"bolt[ed] ... to the metal box", draws those currents into both. Now your
precision ADCs are all reading trash.

But with visibility to where the currents are flowing, or with a
star-grounding scheme, those loop currents stay separate. Say the
connectors are clustered on a front panel, shields grounded to it. That
keeps outside noise out, good. Collect the interior cables (which are still
all grounded to the same point, preferably as coaxially as possible, no
weedy wire links), and bundle them into a single harness. Ferrite beads as
needed. They go over to the PCB, which no longer needs chassis ground at
all.

Or do the brute-force method and use welded chassis compartments to keep the
bignasty away from the quietstuff. Cost doesn't much matter in your test
equipment, but it's a very real tradeoff in production. Production even
likes to avoid metal if they can...

My recent audio mix-amp project motivated me to read, or at least skim,
dozens of articles about /audio/ ground loops. Either Bill Whitlock or
one of the other gurus said something along the lines of ground is a
equal potential myth used by engineers to make their jobs easier.
The exact wording and source of that aphorism are temporarily lost
to me. It's Whitlock who definitely dispels other myths about trying to
use thicker grounds or multiple grounds to fight loops.

To avoid a potential misunderstanding, gurus generally advocate star
grounds, as you did above.

Thank you, 73,

--
Don Kuenz KB7RPU
There was a young lady named Bright Whose speed was far faster than light;
She set out one day In a relative way And returned on the previous night.

 

[John Robertson]

On 2019/08/06 5:09 a.m., Phil Hobbs wrote:

On 8/6/19 4:07 AM, David Nadlinger wrote:
On 05.08.19 1:32 PM, Winfield Hill wrote:
  Here's a DRAFT copy of x-Chapter 1x.1, which starts
  things off, by dealing with wire and connectors.
  Comments and corrections please.

https://www.dropbox.com/s/kz335xwvl5v8gie/1x.1_Wire-%26-Connectors_DRAFT.pdf?dl=1


Regarding that circled capital L in footnote 21: Litzendraht as a
German noun should indeed be uppercase, so the current footnote is
correct (potential disagreements about capitalisation of the loanword
in the body copy notwithstanding).

  — David

Only in German.  In English we capitalize only proper nouns or those at
the beginning of sentences.

Cheers

Phil Hobbs

Well, maybe:

https://www.grammarbook.com/punctuation/capital.asp

Which opens with:

"Capitalization is the writing of a word with its first letter in
uppercase and the remaining letters in lowercase. Experienced writers
are stingy with capitals. It is best not to use them if there is any doubt."

However it depends on the usage... New York City vs the city of New
York, and so on.

John ;-#)#

 

[Phil Hobbs]

On 8/6/19 11:22 AM, John Robertson wrote:

On 2019/08/06 5:09 a.m., Phil Hobbs wrote:
On 8/6/19 4:07 AM, David Nadlinger wrote:
On 05.08.19 1:32 PM, Winfield Hill wrote:
  Here's a DRAFT copy of x-Chapter 1x.1, which starts
  things off, by dealing with wire and connectors.
  Comments and corrections please.

https://www.dropbox.com/s/kz335xwvl5v8gie/1x.1_Wire-%26-Connectors_DRAFT.pdf?dl=1


Regarding that circled capital L in footnote 21: Litzendraht as a
German noun should indeed be uppercase, so the current footnote is
correct (potential disagreements about capitalisation of the loanword
in the body copy notwithstanding).

  — David

Only in German.  In English we capitalize only proper nouns or those
at the beginning of sentences.

Cheers

Phil Hobbs


Well, maybe:

https://www.grammarbook.com/punctuation/capital.asp

Which opens with:

"Capitalization is the writing of a word with its first letter in
uppercase and the remaining letters in lowercase. Experienced writers
are stingy with capitals. It is best not to use them if there is any
doubt."

However it depends on the usage... New York City vs the city of New
York, and so on.

John ;-#)#

But we don't put die Capitals just so die dummkopfen Fremden can
recognize die Nouns.

Cheers

Phil Hobbs

 

[John Robertson]

On 2019/08/06 7:54 a.m., John Larkin wrote:

On Tue, 6 Aug 2019 09:40:40 +0100, Clive Arthur
cliveta@nowaytoday.co.uk> wrote:

On 06/08/2019 03:07, John Larkin wrote:
On Mon, 05 Aug 2019 21:02:26 -0400, Martin Riddle
martin_ridd@verizon.net> wrote:

On 5 Aug 2019 05:32:08 -0700, Winfield Hill <winfieldhill@yahoo.com
wrote:

Here's a DRAFT copy of x-Chapter 1x.1, which starts
things off, by dealing with wire and connectors.
Comments and corrections please.

https://www.dropbox.com/s/kz335xwvl5v8gie/1x.1_Wire-%26-Connectors_DRAFT.pdf?dl=1

No 50-50-50 rule in the connector section?
https://www.connector.com/gold-or-tin-versus-gold-and-tin/
https://www.ramoem.com/uploads/4/4/0/7/44075859/tin_commandments.pdf

Cheers

Tin whiskers.

https://www.dropbox.com/s/h1xfznelskqe3rr/DSC06635.JPG?raw=1


Tinned Whiskas...

https://imgur.com/oI3MVJT

Cheers

SED needs more cat pictures!

No, we don't. Otherwise it will become FB!

John ;-#)#

 

[John Robertson]

On 2019/08/06 7:44 a.m., Don Kuenz wrote:

boB <boB@k7iq.com> wrote:
On 5 Aug 2019 05:32:08 -0700, Winfield Hill <winfieldhill@yahoo.com
wrote:

Here's a DRAFT copy of x-Chapter 1x.1, which starts
things off, by dealing with wire and connectors.
Comments and corrections please.

https://www.dropbox.com/s/kz335xwvl5v8gie/1x.1_Wire-%26-Connectors_DRAFT.pdf?dl=1



Did you notice the one note in this version ?

"Paul, litzendraht, and litz, all need to be lower case."


Also, since you have some handy tools in the chapter, one useful tool
that we use often is the electric enamled wire stripping tool of which
there are a few out there... Might be worth a picture...

https://www.ebay.com/itm/Pro-DF-6-handheld-Magnet-wire-Stripping-Machine-stripper-Cutter-110v-US-STOCK-/333086834927


https://www.aliexpress.com/item/32749284319.html

https://sanshinetechnology.en.made-in-china.com/product/EKTnzLDCuQcp/China-Handset-Enamel-Wire-Stripping-Machine-SS-SM06-Repalce-ABISOFIX-Stripper-.html

A stripping machine sure seems better for my own health than dipping one
end into a solder pot (IIRC) or a jar of paint remover.

Thank you, 73,

A BIC lighter also works fine for removing enamel from 'Magnet Wire'.
The residue usually rubs off, or some 2000 grit wet/dry paper. Don't
want to scratch/nick the copper as it will break there sooner or later!

John :-#)#

 

[John Larkin]

On Mon, 5 Aug 2019 23:29:58 -0700, John Robertson <spam@flippers.com>
wrote:

On 2019/08/05 1:01 p.m., klaus.kragelund@gmail.com wrote:
On Monday, 5 August 2019 21:52:56 UTC+2, klaus.k...@gmail.com wrote:
On Monday, 5 August 2019 16:20:18 UTC+2, Winfield Hill wrote:
Here's a DRAFT copy of x-Chapter 1x.1, which starts
things off, by dealing with wire and connectors.
Comments and corrections please.

https://www.dropbox.com/s/kz335xwvl5v8gie/1x.1_Wire-%26-Connectors_DRAFT.pdf?dl=1


Some comments:

For leaded, you can also use Pin in Paste and laser soldering.

Also instead of wave, you can use selective soldering, which is more controlled than a broad wave

For connectors, fretting corrosion is the real killer.

Use decent amount of gold plating, and use the same plating for both plug and socket. Otherwise it makes no sense to add gold.

Also, too much gold is not better either. Just a waste of money

For fretting, to avoid it all together, use a bleading current so that the connection is always "current" driven at at least mA level. Reduces effects of fretting corrosion dramatically

For connectors, between 2 PCBs, use a floating connection. One PCB locked, the other able to float. That way mating is secure, and thermal expansion cycles does not wear out the connection

For the ac resistances, skin effect, maybe mention dowells equation, mostly used for transformers. Just a couple of layers in a winding can increase the DC resistance 100 fold

Cheers

Klaus

Avoid SMD connectors, they rip off the traces of the PCB

For high quality connections, use pressfit, which also removes the leaded wave solder process

For best possible connections use gat tight connections. Press fit, crimping, splicing, wire wrap


I can't recommend insulation displacement connections - after about ten
to twenty years they start to fail due to (assumption here on my part)
gradual displacement of the insulation leading to the wire strands
losing their stiffness and the connection becomes iffy as the strands
displace.

John :-#)#

These have been very reliable:

https://www.dropbox.com/s/lkn1gxtrmxcvnzc/3p_pair.jpg?raw=1

The red IDC part is

TYCO 640440-3

10 cents.




--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[John Larkin]

On Tue, 6 Aug 2019 09:40:40 +0100, Clive Arthur
<cliveta@nowaytoday.co.uk> wrote:

On 06/08/2019 03:07, John Larkin wrote:
On Mon, 05 Aug 2019 21:02:26 -0400, Martin Riddle
martin_ridd@verizon.net> wrote:

On 5 Aug 2019 05:32:08 -0700, Winfield Hill <winfieldhill@yahoo.com
wrote:

Here's a DRAFT copy of x-Chapter 1x.1, which starts
things off, by dealing with wire and connectors.
Comments and corrections please.

https://www.dropbox.com/s/kz335xwvl5v8gie/1x.1_Wire-%26-Connectors_DRAFT.pdf?dl=1

No 50-50-50 rule in the connector section?
https://www.connector.com/gold-or-tin-versus-gold-and-tin/
https://www.ramoem.com/uploads/4/4/0/7/44075859/tin_commandments.pdf

Cheers

Tin whiskers.

https://www.dropbox.com/s/h1xfznelskqe3rr/DSC06635.JPG?raw=1


Tinned Whiskas...

https://imgur.com/oI3MVJT

Cheers

SED needs more cat pictures!


--

John Larkin Highland Technology, Inc

lunatic fringe electronics