Sputnik 1 was launched on the 4th of October, 1957.
Category Archives: Technology
iPhone and charging
I (deliberately) flattened my iPhone today so I could charge it with its own charger. I about 19:00 I plugged it in to my kill a watt meter to see how much power it uses. I’m assuming the meter isn’t all that accurate, and as it is designed to measure typical household loads its display is in kilowatt hours.
With it plugged in for 19 hours with no load, the kill a watt claims to have consumed 240 watt hours. Which means that it would consume approximately 31.5 watt hours for a 3 hour iPhone charge time.
After charging for 3 hours the iPhone apparently used 40 watt hours, subtracting the 31.5 above gives a results of approximately 8.5 watt hours.
Given the inaccuracy of the devices, that is close enough to the 10 in my previous post for me to say about 10 and roughly in the ballpark of the previous test. Time to go looking for more accurate measuring devices.
iPhone and PV charging
A few weeks ago I was looking around the lab at the remnants of old projects and realised that we probably had enough bits to put together a solar powered charging station for phones. I.e. a 30 Watt PV panel (don’t buy from Farnell), a 12Volt Battery, and a PV charge controller.
I got an old 3 way cigarette lighter socket in Halfords, chopped the cable, added powerpoles, a fused connection to the battery and I now can charge my iPhone at my desk in work.
So, at break yesterday I was asked how much I was saving by charging my iPhone via solar energy. I had no clue, so I let my iPhone die completely last night and re-charged it while checking the charge current on a Watt’s up meter. I got tired of looking at it after 3 hours, but you can see the results on the graph below.
For the first 2 minutes, it stayed steady at 360mA, then the phone switched on and it started charging normally. About 45 minutes at 340mA, before the current started to drop away. At 20ma charging current I stopped the experiment. If we allow a fudge factor for the accuracy of the Watt’s up meter, and the efficiency of the Apple charger (I was running the test off a DC supply) and say about 10watt/hours, that translates to 0.00129 cent per charge or thereabouts.
FASTRAC
Got up this morning, checked my mheard list and saw an entry I hadn’t seen before for FAST2. Checked my logfiles and I found this (output from listen -t -a):
1200mk: fm FAST2 to BEACON ctl UI pid=F0(Text) len 123 08:20:33
0000 F21001633 38263.461363903952.94 -3773326.54 +4430538.23 +0.00
0040 000 +0.00000 +0.00000+1332283286 016 013 004 006 031.
Wow, I wasn’t expecting a full beacon from one of the two FASTRAC satellites, sure, I recently started listening for them, but still, this was a bit unexpected given that I only have an omni-directional antenna, cool though. Now what does it actually mean?
Well, FAST2 is the Amateur Radio callsign for FASTRAC 2 or “Emma” as the satellite is nicknamed. For the rest, I decided to be lazy, Mike, DK3WN has quite a few telemetry decoder programs written, so I downloaded the one for FASTRAC, put it onto a VM, cleaned up my logfile entry a bit and we get.
More detail on what this means is available here. I was wondering about the date and saw this on their facebook page.
The GPS receiver on Emma has not failed, since separation we have had a harder time of commanding her (can do so at very high elevations for a short time) so at the moment one of the microcontrollers that generates part of the beacon… message needs to be reset, which is why the message shows old information. We are in the process of upgrading our groundstation so that we can more easily command Emma and make sure we can reset that microcontroller.
Thanks for your interest and collaboration,
The FASTRAC Team
By the looks of it, the Atmel AVR is still stuck. Hopefully the command team can get it sorted.
World IPv6 Day
In “Celebration” of World IPv6 Day, David suggested that we try a “Crazy Ping”, showing how easy it is to get IPv6 running, even on the most oddball networks. For the heck of it, I configured up this evening the following
A Netbook with an Icom ID-1 D-Star radio plugged into its ethernet port.
A Laptop with both an Icom ID-1 D-Star radio plugged into its ethernet port, and a Kenwood TH-D72 configured in Kiss Mode (9600baud AX.25) plugged into a USB port. The laptop was then configured with an IPv6 over IPv4 tunnel to…
A Desktop, with a Kenwood TM-D710 configured in Kiss mode plugged into an RS-232 port. The desktop also is my sixxs tunnel endpoint.
It isn’t often that you can ‘hear’ someone connect to your computer, but with every packet, the squelch on the TH-D72 opened. So I could hear every packet going to the notebook.
The “Testbed”:
The result:
j0n@scott:~$ ping6 -c 1 2001:770:132:deaf::2
PING 2001:770:132:deaf::2(2001:770:132:deaf::2) 56 data bytes
64 bytes from 2001:770:132:deaf::2: icmp_seq=1 ttl=60 time=3073 ms
--- 2001:770:132:deaf::2 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 3073.686/3073.686/3073.686/0.000 ms
Now why would anyone want to run IPv6 over IPv4 over AX.25? well that is a different question altogether, all I can say is that it works, but not very efficiently.
Micro PV, one year on.
So, after 12 months, what do the numbers say?
Well first a quick reminder of what I have running. A Steca Grid 300 from mysolarshop.co.uk, fed from two Evergreen ES-180RL 180 watt PV panels on the roof of the shed. They are fairly flat on the shed and not in an ideal location. There is about 5-10 degree of tilt on the panels. One of them is ‘facing’ South East, the other North West. So a very non-ideal situation, but useful nonetheless.
I’m using rrtdool to graph the output from an Envi CC128. The CC128 is measuring the output of the Steca grid-tie inverter.
So for the last 12 months rrdtool is saying an ‘average’ of 35 watts is produced every day. So from the back-of-an-envelope, we get 0.035*24*365 or approximately 306 kWh produced, with a value of approximately €55. Not a whole lot really.
Looking at the ‘average’ consumed by the house. It is now showing as 391 Watts (down from 455 the last time I looked). Giving 0.391 *24*365 or approximately 3425kWh (approx €620).
In short, its knocking about 10% off the electricty bill at present, not a lot, but given the panels don’t receive any direct sunlight in mid winter, it isn’t bad at all.
The experiment continues.
Do you remember…
… Mir space station. It de-orbited (crashed into the pacific) 10 years ago today. I remember seeing it on its last visible orbit over Ireland. I was talking to Peter O’Keeffe outside his front door when it streaked overhead on the evening of the 22nd. Quite a sight, and a piece of history.
ISS and Discovery
Monday evening was a rare oportunity with clear skies which allowed for a wonderful sighting of Discovery, OV-103. The ISS and Discovery were both visible, undocked and the ISS appeared to be chasing Discovery across the night sky. This was the last opportunity we had to see the pair and it is something I will never forget. Since then Discovery has successfuly landed and will be slowly making its way to the Smithsonian.
Shortly after undocking, the following picture was taken by an ISS crew member.
Absolutely stunning! Even more amazing is the following picture spotted by Bill Meara, N2CQR (on spaceweather.com) which he posts about here.
It is relatively easy to make out the Discovery and the ISS in the picture. I think you would agree, both are stunning.
Parting of ways
This evening, a long partnership ended. This partnership has existed for approximately 15 years, longer than I’ve owned my car, my (our) house, indeed longer than I’ve been married.
It was a long and amicable relationship, based on mutual dependency and trust. I supplied the power, and, in return, it provided me with light. I am talking of course, about a now defunct, Philips 18watt energy saving lightbulb. It has now joined it’s colleague in lightbulb heaven!
PV Installation, a different story.
From IEEE Spectrum,“My First Year With Solar”. Interesting how subsidies change the game entirely.