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16  Using Arduino / LEDs and Multiplexing / Re: 10 Watt high power LEDs. on: November 05, 2013, 06:04:03 pm
May I join too.

If Leds are on the collector and resistors are on the base, there is nothing to limit current to 400mA. Current is Base current * current gain. You need a resistor in series with the Leds.
Quote
and not use any current limiting (Except on base),

There's nothing to limit the current?

The resistor on the base does! (Ugh)

Perhaps. If you would show a schematic diagram of your circuit here. If not, that is all right too.
17  Using Arduino / LEDs and Multiplexing / Re: 10 Watt high power LEDs. on: November 05, 2013, 04:07:09 pm
May I join too.

If Leds are on the collector and resistors are on the base, there is nothing to limit current to 400mA. Current is Base current * current gain. You need a resistor in series with the Leds.
Quote
and not use any current limiting (Except on base),
18  Using Arduino / Project Guidance / Re: Standalone arduino power generator on: November 05, 2013, 03:54:19 pm
Can you connect your sensors so that they connect power with a relay to your alarm system. Your relay needs extra pair of contacts. The extra pair keeps the relay coil powered. A kind of latching or holding system. Then when processor has done its job, it turns the power off.

19  Using Arduino / Networking, Protocols, and Devices / Re: FM modulation device on: November 05, 2013, 02:43:46 pm
I think there are some approved/legal modules for long distance data transfer. They work around 2,4GHz I think. But 1.5km is a long distance.

By the way, this is an Arduino forum. This has had very little to do with Arduinos so far. You could check other Arduino forums too, like Project Guidance and so on. And try Googling with some magic words like "long distance radio module" or something similar.

Edit: And how about starting a new thread with subject "long distance communication? Your current subject has nothing to do with what you actually wish to do.
20  Using Arduino / Networking, Protocols, and Devices / Re: FM modulation device on: November 04, 2013, 02:35:01 pm
Last time I checked, it was illegal to transmit voice on ISM band. Radio amateurs have a permission to do it on their bands or frequencies. You should check your local authorities what is possible and what not. Or became a radio amateur, a Ham.
21  Using Arduino / Networking, Protocols, and Devices / Re: Radio communication on: November 04, 2013, 11:23:29 am
Try Googling modulation, demodulation, also some studies about RF electronics would help.
22  Using Arduino / Networking, Protocols, and Devices / Re: FM modulation device on: November 04, 2013, 11:20:57 am
I am not sure what it is you want to do. 434MHz is part of the ISM band (and HAM band too). ISM transceivers let you choose either 433-434MHz band or 968 band. And maybe some other bands too.
But what about the FM modulator? This large change of frequency is not usually called modulation. With ISM transceivers you don't have care about modulation, and you really should not, because you may cause interference to others.

This is best I can do without a crystal ball and some magic.
23  Products / Arduino GSM Shield / Re: Can I leave the GSM shield powered ON continously? on: October 27, 2013, 03:22:07 am
It does not help with the current a few years old shield. Everything seems to work, but the shield does not send or receive SMSs.
24  Products / Arduino GSM Shield / Can I leave the GSM shield powered ON continously? on: October 21, 2013, 02:09:48 am
I ask because old GSM modems and shields stop working after day or two. They start working when power goes off and then on again. Worst part is that it is difficult=impossible to see from sketch, is the modem working or not.
25  Using Arduino / Networking, Protocols, and Devices / Re: Netserver example is not working here with the Duemilanove on: October 15, 2013, 02:25:48 pm
Which way it is. At first glance I thought it was Ethernet.begin(mac, ip, gateway, subnet); Is it really necessary to have the subnet field twice?
26  Using Arduino / Networking, Protocols, and Devices / Is it necessary to cycle power of a GSM shield regularly on: October 15, 2013, 01:44:01 pm
A friend of mine has an old GSM shield always powered on. It sends and receives SMSs nothing else. It stops working after day or two and needs power to cycled off and on. I wonder are the newer models any better
27  Using Arduino / Networking, Protocols, and Devices / Re: Only short Ethernet.begin(mac); works on: October 15, 2013, 12:16:05 pm
I wish I could but my ISP has their own Firmware in the box, and it seems I can't access those settings.
28  Using Arduino / Networking, Protocols, and Devices / Re: Only short Ethernet.begin(mac); works on: October 15, 2013, 06:07:13 am
My modem is Bewan ibox IAD ARV4510NPW. If you havn't noticed, you have also written to the "Re: Netserver example is not working here with the Duemilanove" thread. It is also mine. About the same problem but different angle.

The problem with my modem is that there is no setting for DHCP/NAT range, at least not locally. I will check via ISP netsite sometime, because there are some settings there too..
29  Using Arduino / Networking, Protocols, and Devices / Re: Only short Ethernet.begin(mac); works on: October 15, 2013, 02:40:14 am
The example from IDE works with the settings I got. Today DHCP seems to like different address than yesterday.
The result from serial monitor.
IP address: 192.168.100.20
gateway address: 192.168.100.1
subnet: 255.255.255.0
dns address: 192.168.100.1

Does this mean that you should not mix fixed IPs and DHCP.
30  Using Arduino / Networking, Protocols, and Devices / Re: Netserver example is not working here with the Duemilanove on: October 15, 2013, 02:27:28 am
That is a nice little program and it works. Great. Funny thing is, buttons work with IE but not in Firefox.

What is different here. Was it just the IP?
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