On 17/09/14 01:14, Lostgallifreyan wrote:
"gareth" wrote in news:lv91j4$gv9$1@dont-
email.me:

how difficult
it is to manufacture our own plugs and sockets, despite that BNC and N have
been around for 70 years, with SMC some time later!

Why do you want to do that? Some wheels are definitely best not reinvented.
BNC's can be had on eBay as easily as used matchsticks used to be seen on a
street, it's not like we have to make do without. N connectors are expensive,
but there are likely good reasons for that, partly bulk size, precision
requirements, and a lower size of market (by far) than for BNC.

Unless you wanted a bespoke connector at great expense to either do something
really new, or to freeze out an easy chance of anyone connecting to your
stuff, there is no point, the costs are extreme.

I've thought about doing similar from time to time. Not for RF mind
you, BNC serves me well here. My needs are more for audio/control
connectors.

My connection system has varied a bit over the years. In the beginning
I used 8-pin DIN connectors, which worked okay, but didn't quite have
enough contacts to handle all the controls I wanted.

I was looking for a connector that would handle:
- stereo audio (so 3 or 4 lines, depending if they were to share a
return line)
- microphone audio (2 lines)
- PTT
- 4 direction buttons

8 pins wasn't going to suffice for this. So I moved to DB15HD
connectors. Some might recognise these on VGA video cards. I used an
opposite polarity so as to prevent confusing them with a video card.
(one of my adaptor leads allowed me to use headsets with a computer)

These were convenient being all on one connector, and small, but they do
*not* like being exposed to weather much. I was replacing them on a
regular basis. The regular DB15 might be better, I haven't tried.

My next stop has been to split it into two connectors: a DIN5 carries
headset audio (microphone and two speakers), and the PTT and buttons are
on a separate DIN6.

This is more reliable, although I note the connectors have a tendency to
come apart from time to time. I put up with it though, because the same
connectors have lasted much better than the DB15HDs did.

If I did "my own", I'd probably use 6.5mm phono plugs taped together.
Crude, but effective. Kenwood still use a similar arrangement for their
handhelds and it works well enough there.

Stuart Longland wrote in news:ljdoeb-
:

8 pins wasn't going to suffice for this. So I moved to DB15HD
connectors. Some might recognise these on VGA video cards. I used an
opposite polarity so as to prevent confusing them with a video card.
(one of my adaptor leads allowed me to use headsets with a computer)

These were convenient being all on one connector, and small, but they do
*not* like being exposed to weather much. I was replacing them on a
regular basis. The regular DB15 might be better, I haven't tried.


I remember someone posting about a motorbike and weathering of various
plugs (maybe you?). I tried to find any stored posts but failed, having
restored a broken X-news dir from a much earlier saved copy, losing a year's
archiving in the process apparently. I can't remember the details, but I
think he found a part-answer in using lots of PFPE grease to exclude water.
The stuff is often used on vehicles because it tends to stay put and not form
a grinding paste with all the grit that lands on it.

XLR's some in multi-pin forms, mayeb more reliable than multiple 6.5mm jacks,
but I suspect too expensive and bulky if you need a lot at once. I'd probably
use DB25 with adapter as first choice. Bit of heatshrink sleeving such as
used for DIY battery packs, to seal the adapter onto the plug. When the
adapter started to fail, rework the new adapter and new sleeving, rather than
have to do any resoldering. A kind of built-in disposability to save greater
work...

I've looked at DB15HD too, but they're so fiddly to solder I decided not to
do it again.

On 18/09/14 04:52, Lostgallifreyan wrote:
These were convenient being all on one connector, and small, but they do
*not* like being exposed to weather much. I was replacing them on a
regular basis. The regular DB15 might be better, I haven't tried.

I remember someone posting about a motorbike and weathering of various
plugs (maybe you?).

Probably not me. I've been on the back of a motorcycle exactly once and
ridden a quad-bike once. My bikes are very much motor-less.

http://stuartl.longlandclan.yi.org/b.../09/vk4msl-bm/

I can't remember the details, but I
think he found a part-answer in using lots of PFPE grease to exclude water.
The stuff is often used on vehicles because it tends to stay put and not form
a grinding paste with all the grit that lands on it.

Interesting concept, I wonder how that affects conductivity…

Stuart Longland wrote in
:

I can't remember the details, but I
think he found a part-answer in using lots of PFPE grease to exclude
water. The stuff is often used on vehicles because it tends to stay put
and not form a grinding paste with all the grit that lands on it.

Interesting concept, I wonder how that affects conductivity…



Not a lot, I think. I just did a test, I smeared a bit of Krytox on the
tip of my index finger, trying to get it even and about 0.25mm thick, then
zapped it with a peizo gas ignitor. It took several shots to get a spark to
find a weak spot through it, or any sensation of electric shock, so I'd say
it's pretty good, and likely to protect against ESD too if you fill a Dsub
pin shroud with it.

Stuart Longland wrote in
:

I can't remember the details, but I
think he found a part-answer in using lots of PFPE grease to exclude
water. The stuff is often used on vehicles because it tends to stay put
and not form a grinding paste with all the grit that lands on it.

Interesting concept, I wonder how that affects conductivity…


My last post didn't interpret you correctly, I think. Krytox is a light
grease, it's firm but has a low vicosity. When two moving parts meet it tends
to part between them rather than goop between them, hence beign best to use a
good chunk of it. It's easily displaced under the pressure of metal contacs
so I doubt it would harm the electrical contact. It's also white, making it
very easy to examine for gubbins and grit, etc.