Friday, January 30, 2009

iPhone VPN connection to Vista is now working

Something strange happened the other day. I haven't used the iPhone VPN connection since the post was written because I had no use for it. Now I wanted to try it again. This time I got access to all the other ip adresses that were previously hidden for me. I tested this from work so I know I wasn't locally connected. Three things were changed since the last time I tried: The iPhone got new firmware (2.2.1), the wireless network administration was changed from RALink to Windows and Windows Vista probably got some new updates. That's really strange, but oh so cool!

Tuesday, January 20, 2009

Nondestructive cooling for Dreambox DM800 HD


I got sick and tired of the Dreambox DM800 HD locking up all the time and read several places that this was due to heating problems. This happens especially when you run HD channels.

The Dreambox DM800 HD does not contain a fan, so I decided to include one myself. I did not want to destroy anything or cut any wires so I started looking at different pins/connectors that I could connect a fan to. Two options were candidates: the header next to the Broadcom cpu (JTAG header?) and the power supply to the internal SATA harddrive that I have got. Neither were easy to find any good information as to what voltage they had or if they could source sufficient current. I decided to use the same trick that everyone else are using: Connect to the USB port.

I found an old 12V cpu fan that I salvaged from an old computer and stripped the wires. I had a spare USB male to USB female cable that I removed the shielding from, cut the red and black wires, stripped them and connected them to the wires for the fan. Now the fan was running ok. The wires for the fan now goes nicely through the hole where the eSATA connector earlier was connected.

The USB 2.0 standard gives a maximum current of 100mA. At 5V this would be 0.5W. My fan was supposed to draw 1.5W at 12V, but the DM800 has no problem running it. It even seemed to have no problem booting up the first time I connected the power plug.
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Wednesday, January 07, 2009

VPN connection from iPhone to Windows

After some fumbling around I finally figured out how to make a VPN connection from my iPhone to my Windows Vista PC.

To start out I used the guide "Setting up the Vista Point-to-Point Tunneling Protocol (PPTP) Virtual Private Network (VPN) Server". It is a great guide on how to set up a Windows to Windows PPTP VPN connection. The client side is not very well covered, but could easily be found elsewhere on the internet.

I had to set up port forwarding on both the ADSL modem as well as on my wireless router for port 1723. No other changes of settings were necessary on the routers.

After finishing the guide I could not get a VPN connection from either a windows client or from my iPhone. Some web guides have the advise to set the "account" on the iPhone with the syntax "Hostname\Username". This does not change anything. The trick to get a connection is to connect through a different subnet than the VPN server is connected to. This means connecting the iPhone via 3G or a different WiFi Network than the server is physically connected to. This makes sense since you do not need to go to the internet to make a VPN connection if you are allready connected locally.

Now I have a VPN connection from my iPhone to my Vista PC, but I still haven't figured out what I can use the connection to. The iPhone does not have any browser software to browse through local folders on the VPN server and when pinging the subnet I only get reply from the two local adresses for the VPN gateway and the incoming VPN client. I have tried making a port forward to a vnc server, but that didn't work out. I have thus so far not been able to do anything useful with the connection. If anyone have suggestions on how to make it useful, please publish a comment.

Friday, January 02, 2009

PIC desulfator

Look what I got in the mail today: A PIC based desulfator from
courtiestown marine. It took a few hours to solder it, but now it is
ready. Now let's ressurrect some old batteries!