[time-nuts] Power connectors continued

[Bob kb8tq]

Hi

If you have a phase noise under vibration requirement, you do *not* want to use
the “D connector” setup. Go with an SMA ….

Bob

> On Jun 24, 2017, at 7:54 PM, Didier Juges <shalimr9 at gmail.com> wrote:
> 
> I have been forced to use micro-D by a customer on a military power supply,
> not even space rated, it was well over $100 each in 50 piece quantity (I
> think it was a 25 pin).
> 
> However, unless they are mistreated (which is easy for the reason you
> listed), they seem reliable. I do not believe we have replaced one in over
> 400 units shipped and a 15 year period (aside from a couple of prototypes
> that went through hell). That must be one of our better customers...
> 
> The design choice of protecting the pin instead of the socket is baffling.
> 
> 
> On Jun 23, 2017 7:03 PM, "jimlux" <jimlux at earthlink.net> wrote:
> 
> On 6/22/17 4:22 PM, William H. Fite wrote:
> 
>> A good friend of mine, sadly of blessed memory, was a lead engineer for
>> Grumman on the comm systems of the lunar lander. He spoke of small
>> space-rated multi-pin connectors that cost upward of $500 each.
>> 
>> 
>> The Micro-D is widely used in spaceflight, and is a pox on the connector
> world - not only are they expensive, the way the pins and jacks are made is
> almost asking for damage - the pin is shrouded in a hole, and the jack is
> exposed. $100 for a 9 pin wouldn't surprise me.
> 
> Lately, I've been encountering nano-D (Glenair, Omnetics) - they're not as
> delicate, they're smaller.
> 
> 
> 
> 
> 
> 
>> On Thursday, June 22, 2017, Arnold Tibus <arnold.tibus at gmx.de> wrote:
>> 
>> 
>>> Hello,
>>> 
>>> I can second Magnus and want to throw in some more details.
>>> Cannon, Deutsch, Bendix, Souriau, Matrix, Amphenol,  etc. etc. are (big)
>>> companies manufacturing all kind of connectors and are  n o t  connector
>>> type designations! Important are the type numbers of the manufacturer or
>>> higher level specification numbers.
>>> We used in the aircraft and spacecraft business naturally the military
>>> (MS-) numbers listed in the MIL-QPL (or eg. for Spacelab with GSFC spec.
>>> no). Most types of connectors are under these numbers available from
>>> different manufacturers, of course with different manufacturer in house
>>> part numbers. Attention: the 'same' connectors may be bought w/o the
>>> Mil.-spec. sheets with somewhat lesser quality. Important details are
>>> the max. mating number, the contact resistance (e.g. 20 mOhm) and the
>>> max. continuous current, max. Voltage, vibration resistance and
>>> reliability etc.  Of course, this makes good connectors somewhat
>>> 'expensive'. Hirel and non-magnetic gold plated D- subminiture type
>>> connectors do survive e.g. the rocket launch phase (high vibrations),
>>> vacuum and low temperatures and are still used for space projects.
>>> 
>> 
> 
> AMP (and others) sell a lower cost version called the "Circular Plastic
> Connector" or CPC. A coarser screw thread than the round metal MS
> connectors.
> 
> The round connectors (called Bendix connectors by some at JPL, because, of
> course, that was the mfr for some batch of them) have a nice mil-std to
> define them.  There's a Shell, an Insert, and pins/jacks.  You can get
> shells and inserts with different keys and "clocking" to prevent mismates.
> There are coax and triax inserts, high voltage inserts, etc.
> 
> While they're pricey brand new, there are numerous surplus suppliers (Apex
> Electronics in Sun Valley, CA used to have thousands of them).
> 
> You can get them hermetic, vacuum tight, waterproof, locking, non-locking,
> every kind dielectric imaginable, etc.
> 
> 
> 
> 
> 
> 
> 
>>> The D-sub series of connectors was introduced by Cannon in 1952. They
>>> are still available as standard, hirel, and non-magnetic versions. The
>>> contacts were machined contacts forcrimping or soldering connection and
>>> made of massive copper with gold finish. (more see e.g.
>>> https://en.wikipedia.org/wiki/D-subminiature). Example for the standard
>>> 9 pin connector designation (crimp): DEMAM-9S and DEMAM-9P. Today are a
>>> big number of companies producing equivalent types. Cheap ones are
>>> equipped with contacts made of sheetmetal. Nobody should expect then the
>>> same spec. values as reliability, mating numbers, contact power rating
>>> etc.
>>> It is up to the designer of a product to be informed and select the
>>> right quality device for his product ...
>>> 
>> 
> 
> My problem with D-sub is two fold:
> 1) making a chassis hole is a pain - although now, with places like Front
> Panel Express, it's less so.
> 2) the shroud around the plug/male gender is easy to bend if it gets
> stepped on.  Sure, for flight hardware, carefully handled under the
> watchful eye of QA, not an issue, but I have lots of these from my
> not-entirely-mis-spent youth that are bent.
> 
> They do come with removable pins/jacks, and you can get coax flavors too.
> They're fairly compact in a panel.
> 
> 
> Other connectors of interest are those made by Lemo and Hirose.  Lemo are
> locking, pretty rugged when mated, and small for the number of conductors.
> You see them on high end video and medical gear.
> 
> There's also something about double banana plugs and mating jacks. I go
> back and forth between PP and banana plugs for preference.
> 
> BTW, there are panel mounts for PP.
> 
> 
> 
> 
> 
> _______________________________________________
> time-nuts mailing list -- time-nuts at 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 at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.