Archives 2014

Sunday, 30th November 2014 - 19:25:22

Modular PSU Test

Testing this Chinese eBay power supply unit under load with halogens before I fit it. It's going in a TV at work that we are resurrecting. The TV has some stupid external power supply with an even stupider 4 pin security connector on it. I am fitting this inside the TV chassis and fitting an IEC connector on the bottom of the screen so it takes mains directly.

Wednesday, 26th November 2014 - 19:51:51

Rubbed Through EGR Loom

Looks like the engine won't start because the ECU is unhappy that this sensor line is shorted to ground. The loom appears to have rubbed though. A bit of heat shrink and some solder and it's all good.

Wednesday, 26th November 2014 - 08:07:59

Puppet Labs Logo

Mail flows again from my LAN. I managed to totally destroy the config on the exim smarthost... Puppet giveth, puppet can taketh away lol. It was in the wrong host group. #puppetize :D

Friday, 7th November 2014 - 20:49:50


Playing around with a top view magic eye tube: The 6E5. Also a demo of the GR-211 Tubes and some detail on the sockets that I made for them.

Saturday, 18th October 2014 - 20:44:25


Kids are lucky these days.  Hardware is cheap and heavily abstracted in software. USB to TTL serial about $2 AUD. A knock-off Arduino Nano for $4 AUD both with shipping included. Took about 5 mins to get a push button flashing LEDs and sending a message on serial. You can count the lines of code on two hands. Beats the hell out of writing 300 lines of assembler. (but it isn't as fun)

Tuesday, 14th October 2014 - 21:44:29


Tonight I fired up the high voltage power supply and had a go at getting this EM84 display tube going.

+250VDC on the anode, The grid is being operated between -20VDC and 0VDC. The heater on this tube is 6.3V.

Positive terminal on an isolated bench supply is connected to the ground of the +250V supply to give negative voltage required to drive the grid. The negative is fed into pin 1 via a 1meg resistor to ground.

As the grid voltage aproaches 0V, the shadow widens. I put up this video demonstrating adjustment of the grid.

Tuesday, 14th October 2014 - 00:18:21

Logitec LS11

Had a small win with some Logitec speakers today. They were exhibiting poor volume and distortion. My first guess was caps, they looked sound, but were cheap crappy caps. I re-capped it anyway, with no result. There was also a suspect SOT-23 transistor which drives the power LED, when touched, the distortion changed. I deleted the LED circuit and connected the LED with a resistor direct to the power rail. No love. Then I noticed that touching part of the board near the power switch caused the volume to increase and the distortion improve. I shorted across the power switch and the unit came to life. I didn't even suspect the power switch, it is a sealed self-contained unit which is built into the back of the volume control. So I shorted the switch with a blob of solder (no chance getting a replacement dual gang + switch unit). Now the unit works great. Just with no off =)

Saturday, 4th October 2014 - 18:05:45

Tim The Tool Man

Fixed up a bunch of little annoying non-technical things around the house today. Tap handles, leaking toilet cistern, broken light socket and other random stuff.

Wednesday, 1st October 2014 - 18:37:11

PostgreSQL Logo

I headed out to the Postgres high availabililty meetup. The meetup was really good. They went though in a lot of detail the native replication now built in (as of like 9.1 or something) to Postgres. I will be switching my postgres replication from Slonyl to native for sure.

Sunday, 10th August 2014 - 17:02:22

SAN Tool

Somebody managed to snap off the FC to SAS adapter in the back of a set of disk drawers on the SAN. So I cam up with this special tool. =P

Sunday, 27th July 2014 - 20:51:43


I scored this cool little compressor - something I've been missing in the shed for a while now.

Should make a bunch of jobs much easier.

Wednesday, 16th July 2014 - 14:31:49

Power - Turning on two fully stocked SuperMicro MicroCloud Chasssis

Here is what the power does when you turn on two chassis worth of MicoCloud servers. Click the photo to see other power graphs (turning off an IBM chassis full of HS21s.)

Wednesday, 08th July 2014 - 11:11:47


Looks like a trip down to the DC soon to rack up these new drawers. Netapp DS2248. 24x 900G x 4. 86.4TB raw. Drooooool... 

Saturday, 21st June 2014 - 11:32:07


Looool $34.98. Tell 'im he's dreamin...

Friday, 13th June 2014 - 16:54:07


The kids begged Mummy last week to drag this car off the council strip from up the road. The battery is stuffed and it only goes in reverse (switch stuffed). I've replaced the reversing switch with a relay - all it needs now is a battery and it's good to go.

Friday, 13th June 2014 - 13:47:13


Random Elasticsearch fact: When running Elasticsearch from within openvz containers - make sure that you give them veth devices rather than just IP addresses. Otherwise zen discovery will not work.

Proxmox is working out great as a home server. I have many small containers performing various tasks - all with puppet managed config.

This makes it much easier to manage and buildup/teardown when experimenting with different things. Much easier than the previous setup which was one monolithic server which had all the services on it.

Friday, 06th June 2014 - 15:26:06


When working in IT, you often accumulate a lot of hard drives. Here is a box of drives which are going to my mate for scrap. He collects the aluminium and magnets from them.

Friday, 9th May 2014 - 15:50:46


4 Digit Nixie Display prototype is running with the basics without the BCD-10 (4028) and Shift Register (4094) fitted for multiplexing. Running all anodes on for testing.

Unfortunately the previous NPN transistors which I grabbed to drive the bases of the PNP transistors which control the tube anodes were too small. The leakage from emitter to base on the pnp transistors was more than they could handle. Consequently the 4000 series CMOS chips got nuked too =/ I had no throughhole replacements, so I settled on some SMD transistors which I had stashed rated at 400V. No chance of them breaking down. I will also be addding some opto-isolators too...

Tuesday, 22nd April 2014 - 16:38:45


I was given an old tube based high voltage power supply. It looks a bit dodgey - so I'm going to scrap it for parts. There were two nice 150V argon voltage regulation tubes in it though (OD3). There is a potted high voltage transformer module which gives a nice range of taps 425V at 100mA and also a 5V 2A tap for heaters. I will probably end up using this potted module as the basis for a bench supply (A much less scary, much more insulated one).

Saturday, 29th March 2014 - 15:07:15


Today I built a chisel sharpening jig loosly based on John Heisz' design, without the trimmings. It turned out pretty well. Fixed 30 degree bevel, not adjustable. Two of the chisels were pretty far gone, so I ran them on the belt sander first to get the bulk of the material removed. This also fixed the leading edge and made it square again.

Wednesday, 26th March 2014 - 18:24:36

Logstash Logo

I've been implementing logstash at work. Interesting stuff. The elasticsearch cluster is up and running and working great. There isn't really anything to give it a really solid workout with just yet. I have been feeding it about 3000 lines a day worth of power data which I am graphing with Kibana, but that's about it. For starters I've got 180-odd machine cluster which I am going to be reading logs from with the logstash agent and sending them over to elasticsearch. There will be a redis cluster sitting between elasticsearch and the logstash agents. I decided to implement two haproxy/keepalived setups with floating IPs for the Elasticsearch and for the redis cluster. I went with this because although Elasticsearch takes care of this by it's self normally, some code does not handle being given more than one IP or hostname to contact Elasticsearch with, the same goes for the redis. So floating IPs will solve this, it will also mean that I can add more nodes and not touch the config on either the logstash agent or on the logstash redis/elasticsearch boxes. I can't wait to try it out, the individual bits are all happy and some of the parts which can communicate are tested. Currently I'm waiting on changes and approvals and stuff to go through so I can open up the required ports and install the logstash agents.

Thursday, 20th March 2014 - 14:35:43


A roof space adventure! I had to get into the ceiling to investigate a noise we were hearing, which sounded like it was coming from in the ceiling. Of course this noise is intermittant and did not occur after all the effort of getting into the roof. I had to cut a piece of pine to fit across the bath tub to hold the ladder up under the manhole. It's in a really stupid spot (see photos). During the investigation I also discovered another reason why the airconditioning performs so poorly in this house. It appears that rather than getting a new AC plant when the house was extended, the owners simply bodged on another duct. I mean bodged, The main outlet to the airco is a trapezium shape with two ducts coming out like normal. They have just cut a hole in the top face and bodged another outlet on - the cutout is still sitting on top of the unit. I may modify this later, it's crap, you have to run every outlet all the time, there is no day/night modes to switch between bedrooms and living areas. I also discovered that there is a massive water heater in the ceiling too.

Thursday, 13th March 2014 - 13:32:54

Puppet Labs Logo

Finishing up the last day of Puppet training today in the city. It's been good to get a better understanding of how to start out from scratch and fill in a lot of gaps in fundamental knowledge which I missed being self taught. At work I help maintain existing modules, but rarely write new modules - so this is great. Another cool tool for the toolbox.

Sunday, 9th March 2014 - 13:27:23


Racked up an interesting bit of kit today. Very nice in deed. Supermicro Microcloud 5037MR-H8TRF. This beastie fits eight E5-2600 v2 based systems into just 3U height. The units that we have currently are fitted with 32GB of RAM, but can take up to 128GB. The additional dual gigabit ethernet modules were removed and dual 10G SFP+ adapters were fitted. Each blade also has IPMI and the ability to directly plug in KVM (via dongle). They look awesome. The front of the chassis contains 16 3.5" drives. Two disks per blade. Click the thumbnail for more images.

Friday, 07th March 2014 - 13:36:02


Today I made a compact "gaming station" to get the kids off the main TV. They can play the Wii and the Playstation on this unit. It also contains all the games and crap that go along with the consoles. It is made from an old baby change table which I basically cut in half on the table saw. It uses a TV screen with AV in which a mate gave me. A quick win for not much work.

Wednesday, 06th March 2014 - 00:04:19

Triple Screen ASCIIquarium

Triple Screen ASCIIquarium =)

Saturday, 1st March 2014 - 10:51:15

HP 2848 Switch eBay

Swich from eBay arrived today. Pretty good score - less than $100. 48 Port gigabit managed switch. HP 2848. Judging by the box it came it, it was ex-auction (grays online or something) and had never been used. The "refer to guide" sticker was still over the power inlet. W00t.


Friday, 28th February 2014 - 18:33:47

PostgreSQL Logo

Just finished implementing a postgres backed powerdns system for internal dns including slony replication to a remote node which also has powerdns on it. I wrote some python which I hooked into the dhcpd commit, release and expire events that creates forward and reverse DNS entries for specific ranges of DHCP when leases are given and removes them when they expire or when they are released. The records are created with 60 second TTLs, so it seems to work pretty well. I got tired of editing bind files, now I can make DNS changes programatically or in a web GUI like poweradmin or something. There are also a bunch of new sub domains for lab, esx, vpn and proxmox hosts which are easier to manage now.

Thursday, 27th February 2014 - 20:21:51


Setting up current version of yum Postgres on CentOS machines...

rpm -Uvh</p>
<p>yum install postgresql93-server --enablerepo=pgdg93

Tuesday, 18th February 2014 - 14:48:34


These boxes now have Debian installed and are ready to go to the Datacentre. They are going to be part of my logging project and will be hosting an Elasticsearch cluster. These are nice machines, they should do well. Massive IO with all these disks, heaps of RAM and 16 cores to index all the things =)

Sunday, 9th February 2014 - 20:40:04

Memtest Bad Mobo

Looks like maybe heat was not the issue. Perhaps the mainboard is toast. During RAM testing with single sticks in combination with differing single slots I discovered that my RAM appears to be good, but for some unknown reason the board is trying to run DDR3 on the second slot at just 200MHz. The machine passes both sticks in the first slot and also does not exhibit any issues with just one stick of RAM in the first slot. Fun times =(

I was able to bandaid it while I wait to get a new board by underclocking the RAM substantially.

Sunday, 9th February 2014 - 14:19:01


Today my random eBay shunt box arrived. I spotted this one on eBay and bought it straight away. $15. I stripped it during lunch at work and kept only the voltage and current meters and some switches. Pretty good salvage for $15, considering a 300V volt meter and 30A current meter with it's shunt is probavly worth over $50.

Thursday, 6th February 2014 - 19:38:00


House server "brick" from atom with 1G to Xeon x3220 with 8G and a mobo that has SATA2. It now doesn't fall to it's knees when indexing things in elasticsearch or when you glance at it. I'm over my super low power phase, It needs to be able to get shit done...

Desktop to 8G RAM, it now plays BF4 much more reasonably.

Thursday, 6th February 2014 - 15:11:40


Today I spent a bit of time stripping down the TV boards that I salaved. I was looking for the flybacks (mainly), but also saved some high voltage transistors and diodes from the TV boards.

Tuesday, 4th February 2014 - 19:31:02


Terrible problems with the PC at the moment, it looks like heat is the issue. I tore everything down and cleaned it.

Monday, 27th January 2014 - 17:29:46


Today I managed to get my Mazilli ZVS Oscillator running with a flyback out of a PC monitor which I scrapped. There are more photos in the gallery.

Saturday, 25th January 2014 - 15:13:45

Shelves All Finished

The new lab shelves are finished and the gear is all set up. They look great.

Friday, 24th January 2014 - 16:36:47

Sash Clamps

The sash clamps have arrived and work great. eBay specials of course. They were fun to walk home with - 12kgs. The picture shows one of the shelves with edge banding being glued up.

Thursday, 23th January 2014 - 23:30:18

Cisco 1231AP

My Cisco 1231 access point arrived. This is going outside. Not bad for $30.

Runs off POE, does 802.11B and G, handles multiple SSIDs and VLANS. Fun =)

It will take a tiny bit of messing around because it doesn't have an autonomous IOS on it, the LWAP image will have to go.

Friday, 17th January 2014 - 17:35:17

Edge Banding Trimmer

Today I used a jig that I made aaages ago for trimming edge banding. The jig worked great, but the result wasn't that great. The banding was not being adequately clamped to the shelving - so there were gaps. I broke the edge banding off, sanded the glue off the shelf and the banding and I'm going to wait until I get some sash clamps.

Monday, 13th January 2014 - 19:47:56

Supports Bolted on 1

The glue is now dry on the shelving supports and they are now bolted onto the desk. They look good so far.

Sunday, 12th January 2014 - 17:28:39

NetApp Box

Just finished installing two NetApp filers and 7 24 disk shelves at the data center. Approximately 300kg of gear. 150TB raw storage. It took us 3 car trips. Unfortunately I can't take photos at the DC. So here is a photo of the box =)

Friday, 10th January 2014 - 12:27:56

Shelf Supports 2

I started work today on a new set of shelves which will bolt to the back of my lab desk. I am using standard 70x35mm cheap construction pine with 18x90 finished pine for horizontals. The shelves themselves will be made from a big sheet of black melamine MDF that I salvaged from the store I used to work in.

Sunday, 5th January 2014 - 17:59:30

Debian Logo

Hot plugging RAM into a Debian VM (for shits and giggles). It actually works.

for a in `ls /sys/devices/system/memory/memory*/state`;
echo "online" > $a;
done 2>/dev/null;
grep offline /sys/devices/system/memory/memory*/state

Saturday, 4th January 2014 - 12:40:41

Baby Drills and Taps

Baby drills and taps have arrived (terrible photo). M3 and M4 drills. 2.5mm and 3.5mm drills. I can now drill and tap CPU heatsinks for MOSFET cooling.

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