Powering Mio In The Cockpit

Hi,

I stand corrected.

Paul Remde

"ZL" wrote in message
m...
The 302 manual (pg 25) says pin 4 of the RJ11 is
"+5V = Device power – fuse-limited to 0.9 Amp"

pin 6 and 8 of the DB-9 connector are
"+5 volt power from 302 to connected device; fuse-limited to 0.9 Amp"

I've used the DB-9 connector on my 302 to provide +5V power to an iPAQ for
7 years now. Cambridge and others have sold connectors for that purpose
for a long time. I also have a 303 hooked up to the RJ11 plug.

Manual is available at the Cambridge website.

-Dave

On 11/1/2011 6:33 PM, Paul Remde wrote:
Hi Dan,

That is a very bad idea! The RJ connector on the back of the 302 is for
connection to the 303 LCD display. The 303 is a low voltage device. Your
Mio is not. I'm not certain, but I fear you will fry something in the
302.

Best Regards,

Paul Remde

"Dan Marotta" wrote in message
...
While I had my panel apart the other day, I noticed the RJ jack in the
back of the 302. Since I had half a Cambridge cable, I plugged it in,
powered up, and measured voltage across the red and black leads - 5v!

I took a standard USB cable that fits the Mio, cut it, and measured
the red and black leads - again, 5v! Tomorrow, I'll connect the two
cables together and run the Mio of the ship's batteries.

Dan

Why are my posts red (color, at least on my laptop)?

Thanks, Paul - I did not consider looking up the specs, which I will do.

Dave, I read in the 302 manual about the 0.9A internal fusing in the 302.

The cigarette lighter power cord that comes with the Mio is terminated with
a mini USB connector so there should be no power/data issues. The data
lines are not connected in this case.

I will try to find the power requirements of the Mio online. I opened it up
and it has a small (physically) battery so I suspect its power needs aren't
too big.

I could wire a 12v power cord into the main bus of the glider, but that's
large and there's not a lot of room inside the LAK's panel. Besides, simply
plugging in is so much easier!

I'll report back what (if anything) I find.


"Paul Remde" wrote in message
...
Hi,

I stand corrected.

Paul Remde

"ZL" wrote in message
m...
The 302 manual (pg 25) says pin 4 of the RJ11 is
"+5V = Device power – fuse-limited to 0.9 Amp"

pin 6 and 8 of the DB-9 connector are
"+5 volt power from 302 to connected device; fuse-limited to 0.9 Amp"

I've used the DB-9 connector on my 302 to provide +5V power to an iPAQ
for 7 years now. Cambridge and others have sold connectors for that
purpose for a long time. I also have a 303 hooked up to the RJ11 plug.

Manual is available at the Cambridge website.

-Dave

On 11/1/2011 6:33 PM, Paul Remde wrote:
Hi Dan,

That is a very bad idea! The RJ connector on the back of the 302 is for
connection to the 303 LCD display. The 303 is a low voltage device. Your
Mio is not. I'm not certain, but I fear you will fry something in the
302.

Best Regards,

Paul Remde

"Dan Marotta" wrote in message
...
While I had my panel apart the other day, I noticed the RJ jack in the
back of the 302. Since I had half a Cambridge cable, I plugged it in,
powered up, and measured voltage across the red and black leads - 5v!

I took a standard USB cable that fits the Mio, cut it, and measured
the red and black leads - again, 5v! Tomorrow, I'll connect the two
cables together and run the Mio of the ship's batteries.

Dan

Well... All the Mio specs I could find are that it has a 750 mAH battery
which should last for 2.5 hours (and I know from experience that that is
about right). At 5 volts that would indicate a current draw of 288 mA.

I called Mio tech support and they confirmed that number so running the Mio
from a 900 mA port on the 302 should be no problem at all.

Thanks to Paul, for raising a red flag, and to Dave for describing his
setup.


"Dan Marotta" wrote in message
...
Why are my posts red (color, at least on my laptop)?

Thanks, Paul - I did not consider looking up the specs, which I will do.

Dave, I read in the 302 manual about the 0.9A internal fusing in the 302.

The cigarette lighter power cord that comes with the Mio is terminated
with a mini USB connector so there should be no power/data issues. The
data lines are not connected in this case.

I will try to find the power requirements of the Mio online. I opened it
up and it has a small (physically) battery so I suspect its power needs
aren't too big.

I could wire a 12v power cord into the main bus of the glider, but that's
large and there's not a lot of room inside the LAK's panel. Besides,
simply plugging in is so much easier!

I'll report back what (if anything) I find.


"Paul Remde" wrote in message
...
Hi,

I stand corrected.

Paul Remde

"ZL" wrote in message
m...
The 302 manual (pg 25) says pin 4 of the RJ11 is
"+5V = Device power – fuse-limited to 0.9 Amp"

pin 6 and 8 of the DB-9 connector are
"+5 volt power from 302 to connected device; fuse-limited to 0.9 Amp"

I've used the DB-9 connector on my 302 to provide +5V power to an iPAQ
for 7 years now. Cambridge and others have sold connectors for that
purpose for a long time. I also have a 303 hooked up to the RJ11 plug.

Manual is available at the Cambridge website.

-Dave

On 11/1/2011 6:33 PM, Paul Remde wrote:
Hi Dan,

That is a very bad idea! The RJ connector on the back of the 302 is for
connection to the 303 LCD display. The 303 is a low voltage device.
Your
Mio is not. I'm not certain, but I fear you will fry something in the
302.

Best Regards,

Paul Remde

"Dan Marotta" wrote in message
...
While I had my panel apart the other day, I noticed the RJ jack in the
back of the 302. Since I had half a Cambridge cable, I plugged it in,
powered up, and measured voltage across the red and black leads - 5v!

I took a standard USB cable that fits the Mio, cut it, and measured
the red and black leads - again, 5v! Tomorrow, I'll connect the two
cables together and run the Mio of the ship's batteries.

Dan

I called Mio tech support and they confirmed that number so running the Mio
from a 900 mA port on the 302 should be no problem at all.

- Not sure if the internal fuse of .9A is internally wired to this
particular 5V output. When I tried using my HX4700 with the C302 via
the serial cable, that was wired to provide the 5V out of the 302, the
302 would not function properly. The vario would black out and it
seemed that the ipaq is drawing all the power out if, even though the
input to the C302 had plenty of power. In a nutshell, I did not damage
the C302, but I don’t believe there is a fuse inside - I measured
later that the half charged HX4700 was drawing about 1.5 Amps and C302
would only work with fully charged HX4700 because the lower amp
consumption. Considering MIO tech support is probably located where it
is I would not put too much faith in them especially since you can
damage the C302.

Safe soaring,

GK

Hi GK,

I suspect that the iPAQ's battery was low. The hx4700 draws only about 300
to 400 mA when the battery is fully charged. But it can draw well over 1 A
when the battery is low. The 302 would probably work fine if you connected
the hx4700 to it when the battery was fully or nearly fully charged.

I've used hx4700 units with 302s many times with no problems.

Best Regards,

Paul Remde
Cumulus Soaring, Inc.

"GK" wrote in message
...

I called Mio tech support and they confirmed that number so running the
Mio
from a 900 mA port on the 302 should be no problem at all.

- Not sure if the internal fuse of .9A is internally wired to this
particular 5V output. When I tried using my HX4700 with the C302 via
the serial cable, that was wired to provide the 5V out of the 302, the
302 would not function properly. The vario would black out and it
seemed that the ipaq is drawing all the power out if, even though the
input to the C302 had plenty of power. In a nutshell, I did not damage
the C302, but I don’t believe there is a fuse inside - I measured
later that the half charged HX4700 was drawing about 1.5 Amps and C302
would only work with fully charged HX4700 because the lower amp
consumption. Considering MIO tech support is probably located where it
is I would not put too much faith in them especially since you can
damage the C302.

Safe soaring,

GK

On Wed, 02 Nov 2011 13:18:20 -0500, Paul Remde wrote:

I suspect that the iPAQ's battery was low. The hx4700 draws only about
300 to 400 mA when the battery is fully charged. But it can draw well
over 1 A when the battery is low. The 302 would probably work fine if
you connected the hx4700 to it when the battery was fully or nearly
fully charged.

I'd agree. I have an ancient iPAQ 3630 which specifies that its 5v
connection can draw up to 1.4 amps from a charger or whatever. As it is
supposed to run for 3 hours from a full charge and has an 800 mAh
battery, that implies that it uses around 270 mA during normal operation.

Its also worth remembering that the USB 2.0 spec says a connection should
be rated for 800 mA - and there are some devices that will try to draw
more than that. However, it would be wise to size the Mio power supply
for at least 1.5 amps[1] rather than 0.4 amps because at some point
Murphy guarantees you *will* connect the Mio with with an almost fully
discharged battery.

For what its worth, I bought a cheap 12v charging cable off eBay for my
iPAQ and took it apart. The cigar-lighter end contains a very small
12v - 5v converter rated at 1.5 amps. I installed it in a small metal
box (these small switch-mode voltage converters may stick out a lot of RF
hash) and permanently wired its 12v side to the glider battery. I have
lots of bad experiences with those cigar lighter plugs leaping out of the
socket for no apparent reason, so wasn't going to risk using one: besides
they are very bulky. The iPAQ is long retired, but I'm still using the
voltage adapter, which has to date powered the iPAQ 3630, a Garmin GPSII+
and, currently, my Binatone B.350 PNA.

[1] or the Mio's rated max input current, whichever is largest.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

Disregarding Murphy, the Mio will always be connected to external power, so
no low battery.

I hooked it up yesterday and spent a half hour or so sitting in the cockpit
making glider noises. Everything looks good. I appreciate the advice about
the 302 acting up and, should I see that sort of behavior, will simply
switch batteries or shut off the Mio and see if there's any change.

It's hard to imagine the Mio using much more than 300 mA.


"Martin Gregorie" wrote in message
...
On Wed, 02 Nov 2011 13:18:20 -0500, Paul Remde wrote:

I suspect that the iPAQ's battery was low. The hx4700 draws only about
300 to 400 mA when the battery is fully charged. But it can draw well
over 1 A when the battery is low. The 302 would probably work fine if
you connected the hx4700 to it when the battery was fully or nearly
fully charged.

I'd agree. I have an ancient iPAQ 3630 which specifies that its 5v
connection can draw up to 1.4 amps from a charger or whatever. As it is
supposed to run for 3 hours from a full charge and has an 800 mAh
battery, that implies that it uses around 270 mA during normal operation.

Its also worth remembering that the USB 2.0 spec says a connection should
be rated for 800 mA - and there are some devices that will try to draw
more than that. However, it would be wise to size the Mio power supply
for at least 1.5 amps[1] rather than 0.4 amps because at some point
Murphy guarantees you *will* connect the Mio with with an almost fully
discharged battery.

For what its worth, I bought a cheap 12v charging cable off eBay for my
iPAQ and took it apart. The cigar-lighter end contains a very small
12v - 5v converter rated at 1.5 amps. I installed it in a small metal
box (these small switch-mode voltage converters may stick out a lot of RF
hash) and permanently wired its 12v side to the glider battery. I have
lots of bad experiences with those cigar lighter plugs leaping out of the
socket for no apparent reason, so wasn't going to risk using one: besides
they are very bulky. The iPAQ is long retired, but I'm still using the
voltage adapter, which has to date powered the iPAQ 3630, a Garmin GPSII+
and, currently, my Binatone B.350 PNA.

[1] or the Mio's rated max input current, whichever is largest.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |