17 Jun
2013
17 Jun
'13
11:55 a.m.
On Sun, Jun 16, 2013 at 09:49:53PM +0100, Tony Duell wrote:
It does mean 2.2uF. A common convention is to put the miltiplier letter
in place of the decimal point, so 4.7kOhms -> 4k7, etc. The idea is that
the deciaml point cna be easily missed, the letter can't.
So 2.2$\mu$F would become 2$\mu$2. But since $\mu$, and neither is
$\Omega$, the convention for resisotrs was to turn 2.2Ohms into 2R2. Adnd
for some unknown reson, this was also used for _microfarads)_ on
capacitors, so 2R2 means 2.2uF. No, I don't mich like it either.
Soecondly, IIRC the disptribution panel is
essentially just connectors.
It's certainly *mostly* just connectors, but the H317F panel also seems to
have four resistors (47 ohms) and a cap (not sure what 2R2uF means -- if they
meant 2.2uF they'd say that), and a 0-ohm jumper to disconnect the cap (for higher bit rates IIRC). Last time I went digging for
schematics I couldn't
find them, either online or in any of the mounds I keep tripping over.
I'd love to find prints -- I've got a dinky little multiport RS232-to-20mA
design I'd like to finish up, and having the H317F-style Berg connector on
I probalby have the DJ11 Prints, I wonder if the distribution panel has
the same pinout.
In any case, the distribution panel is simple, and presumalby has the same
circuitry repeasted 16 times. To trace out the schematic shouldn't take long.
it would make it very easy to wire to existing DZ11C
installations (vs.
transferring all the screw terminals). But I also would get a kick out of
doing a PCB layout for a clone, if that would help (I have only the one
H317F so, sorry I can't spare the real thing).
Now, high speed is multi-megabits per second or more.
-tony
Given that the current loop signals are pretty low
speed, you would
almost certainly get away with taking a length of ribbon cable, putting a
BERG socket on one end, splitting the other end into individual wires and
puttign them on screw terminals.
I don't know if 9600 baud counts as high speed but I was *very* happy with