"Gert Been" wrote in message
...

Hi,
Talking about "decent" multiplexers, all our NMEA multiplexers have
"automatic GPS back-up switching" (plus many other NMEA sentence
management
features). Read about it he
http://brookhouseonline.com/gps_backup_switching.htm . I have been
playing with the idea to add a buzzer to warn the user when it switches
to
the backup GPS. As the "no GPS data" detection is already present, this
is
very simple to do. If there is sufficient interest, we'll include it as
a
standard feature. If you want it NOW, we'll add a buzzer to the present
model for a small charge if you decide to buy one.
Wout

Ehh, talking about "Decent" multiplexers: decent multiplexers have
isolated
inputs, yours don't.

I just connected one of yours to a differential NMEA talker output. I can
now hear all NMEA data on my SSB!!

While trying to find out what's wrong, I found that all inputs on your
multiplexer have the B terminals connected to ground!!! NMEA inputs are
supposed to be isolated. Your grounded B terminals on the inputs
effectively
short-circuit any properly designed talker. Was it that hard to add 50
cents
worth of optocouplers?

Gert


Our new multiplexers have opto-isolated inputs and are compliant with CE
emission requirements. Strange that I first hear from you via this
newsgroup. Would you not have contacted us with your complaint if you had
not come across this newsgroup thread? You say you have just installed one
of our multiplexers. I have checked our records, but we don't have you
listed as a recent direct customer.
If you have any kind of problem with a multiplexer, we'll be happy to assist
if you contact us via the normal channel. Your problem can be easily
resolved. All you need to do is send us an email and let us know where and
when you bought your multiplexer.
Wout

"Meindert Sprang" wrote in
:

Mmmm, interesting option :-)
I know that the Seatalk-NMEA brigde from Raymarine has a dedicated
alarm output. But this one only works on Seatalk alarms.

A microcontroller-and-electronics hobbyist could make this for a few
bucks though...

Meindert




I feel a whole new product coming online......(c;

MAKE THE DAMNED ALARM LOUD ENOUGH TO WAKE EVERYONE ABOARD!!

Thanks....(c;

You can hardly hear a Raymarine RL70CRC alarm sitting right in front of it
in a 10 knot wind....stupid, stupid, STUPID!

"Gert Been" wrote in
:

Ehh, talking about "Decent" multiplexers: decent multiplexers have
isolated inputs, yours don't.

I just connected one of yours to a differential NMEA talker output. I
can
now hear all NMEA data on my SSB!!

While trying to find out what's wrong, I found that all inputs on your
multiplexer have the B terminals connected to ground!!! NMEA inputs
are supposed to be isolated. Your grounded B terminals on the inputs
effectively short-circuit any properly designed talker. Was it that
hard to add 50 cents worth of optocouplers?

Gert



This is one of my pet peeves with most manufacturers. STupid Icom's really
expensive M-802 uses a BNC RF connector that only has ONE WIRE and ground
to hook the NMEA data to the transceiver for DSC/GMDSS GPS input. They
should all be HUNG! If everything had a balanced line like NMEA was
designed for, I could probably transmit on HF without tearing up the whole
boat's NMEA network....(d^

"Wout B" wrote in
:

Our new multiplexers have opto-isolated inputs and are compliant with
CE emission requirements. Strange that I first hear from you via this
newsgroup. Would you not have contacted us with your complaint if you
had not come across this newsgroup thread? You say you have just
installed one of our multiplexers. I have checked our records, but we
don't have you listed as a recent direct customer.
If you have any kind of problem with a multiplexer, we'll be happy to
assist if you contact us via the normal channel. Your problem can be
easily resolved. All you need to do is send us an email and let us
know where and when you bought your multiplexer.
Wout



Translation - "Shhhh.....don't say bad things about boat products in public
forums like newsgroups".......

"Wout B" wrote in
:

Hi,
Talking about "decent" multiplexers, all our NMEA multiplexers have
"automatic GPS back-up switching" (plus many other NMEA sentence
management features). Read about it he
http://brookhouseonline.com/gps_backup_switching.htm . I have
been playing with the idea to add a buzzer to warn the user when it
switches to the backup GPS. As the "no GPS data" detection is already
present, this is very simple to do. If there is sufficient interest,
we'll include it as a standard feature. If you want it NOW, we'll add
a buzzer to the present model for a small charge if you decide to buy
one. Wout
Brookhouse

I'd rather see shielded connectors so I can run shielded pair cables and RF
bypassing of all inputs to keep the HF SSB from screwing all the NMEA crap
attached to it. Shielding everything would also make it so we could HEAR
the HF receiver and get our WEFAXes without the constant drone of NMEA
radiated interference from all the unshielded, unbalanced connections with
just open wires sticking out of things. NMEA needs to get its act together
and enforce some standards on its members....

Of course, we could dump all this proprietary crap and just wire the boat
for Ethernet, negating the need for multiplexers in 1970 serial
connections. Ahhhh....addressable Ethernet instruments all speaking the
SAME language through a good $49 wireless Netgear router to the wireless
laptop in my berth....(c;

Larry,
Do you have ferite beads at both ends of all your NMEA cables? If so, do
they help?
krj

Larry W4CSC wrote:
"Wout B" wrote in
:


Hi,
Talking about "decent" multiplexers, all our NMEA multiplexers have
"automatic GPS back-up switching" (plus many other NMEA sentence
management features). Read about it he
http://brookhouseonline.com/gps_backup_switching.htm . I have
been playing with the idea to add a buzzer to warn the user when it
switches to the backup GPS. As the "no GPS data" detection is already
present, this is very simple to do. If there is sufficient interest,
we'll include it as a standard feature. If you want it NOW, we'll add
a buzzer to the present model for a small charge if you decide to buy
one. Wout
Brookhouse


I'd rather see shielded connectors so I can run shielded pair cables and RF
bypassing of all inputs to keep the HF SSB from screwing all the NMEA crap
attached to it. Shielding everything would also make it so we could HEAR
the HF receiver and get our WEFAXes without the constant drone of NMEA
radiated interference from all the unshielded, unbalanced connections with
just open wires sticking out of things. NMEA needs to get its act together
and enforce some standards on its members....

Of course, we could dump all this proprietary crap and just wire the boat
for Ethernet, negating the need for multiplexers in 1970 serial
connections. Ahhhh....addressable Ethernet instruments all speaking the
SAME language through a good $49 wireless Netgear router to the wireless
laptop in my berth....(c;

"Gert Been" wrote in message
...

Ehh, talking about "Decent" multiplexers: decent multiplexers have
isolated
inputs, yours don't.

I just connected one of yours to a differential NMEA talker output. I can
now hear all NMEA data on my SSB!!

While trying to find out what's wrong, I found that all inputs on your
multiplexer have the B terminals connected to ground!!! NMEA inputs are
supposed to be isolated. Your grounded B terminals on the inputs
effectively
short-circuit any properly designed talker. Was it that hard to add 50
cents
worth of optocouplers?

Ouch!!!

Meindert

"Larry W4CSC" wrote in message
...

This is one of my pet peeves with most manufacturers. STupid Icom's
really
expensive M-802 uses a BNC RF connector that only has ONE WIRE and ground
to hook the NMEA data to the transceiver for DSC/GMDSS GPS input. They
should all be HUNG! If everything had a balanced line like NMEA was
designed for, I could probably transmit on HF without tearing up the whole
boat's NMEA network....(d^

I agree completely. NMEA should have simply revoked membership of anyone not
adhering to the standard. The NMEA-0183 spec is very clear on the naming of
the terminals, what signals they should carry and the required isolation on
every input. So if everyone adhered to the standard, connecting NMEA would
have been as easy as connecting a ligthbulb.....

Meindert

"Larry W4CSC" wrote in message
...
I'd rather see shielded connectors so I can run shielded pair cables and
RF
bypassing of all inputs to keep the HF SSB from screwing all the NMEA crap
attached to it. Shielding everything would also make it so we could HEAR
the HF receiver and get our WEFAXes without the constant drone of NMEA
radiated interference from all the unshielded, unbalanced connections with
just open wires sticking out of things. NMEA needs to get its act
together
and enforce some standards on its members....

Funny thing is: you don't need shielded connectors to be HF-quiet. The
physical size of two screw terminals and an inch of bare wire ends are
simply not enough to be able to radiate sufficient RF. What does radiate on
HF are long cable runs that are either unshielded or unbalanced. Raymarine
have put our multiplexers to the test to comply with IEC945 for instance,
which limits for susceptibility and emission are rougly ten times more
stringent than FCC Part 15 class B. And it passed that test while being in a
plastic box and having screw-terminals. The really important thing is to
have it wired correctly and, most important, not to connect a shield *at
both ends*.

Meindert

"krj" wrote in message
. ..
Larry,
Do you have ferite beads at both ends of all your NMEA cables? If so, do
they help?

Ferrite beads don't do much on HF, but all the more on VHF. But like I said
in me other replay, it's more important to terminate the wire correctly. If
you have a shield, do not use it as a signal return as with coaxial cable.
Only connect it on one side so no current can flow through the shield,
otherwise it will radiate being a perfect antenna.

Meindert