It is a bit sad…

… when you eagerly wait for a mail from a cron job to tell you that a machine you could usually reach at least once a week but that now, given the situation, is away from your reach, is still alive and doing its job.

Anyway, given a properly configured MTA like postfix, it is as easy as adding a line like

MAILTO=some.address@provider.com

to your cron configuration.

A.C.

Posted in Small Talk | Leave a comment

Waterblock sanding

Materials:

  • grit 800 wet sanding paper
  • water
  • elbow grease
  • time

Before

After

A.C.

Posted in Hardware | Leave a comment

AD584JH chinese voltage reference board

I bought some time ago a cheap AD584JH voltage reference board from the usual online auction site.

It is a couple of weeks that the board is powered on and measured by my HP3456A while the temperature of the room is measured by a DS18B20.

Moreover the Solartron 7159 is measuring the output voltage of the power supply that powers the voltage reference board.

I am just saving the data once a minute but it is a nice exercise with GPIB. I hope to write soon an R script to get some nice graph of the data.

A.C.

Posted in Analogic, Electronics, Equipment | Leave a comment

Re-streaming an ONVIF IP camera stream with ffmpeg and VLC

I had to test work done on an ONVIF IP camera and so I needed a way to see whatever the camera was streaming.

The first catch was that I couldn’t use any software that worked with the camera mainly because there were very few that worked or seemed to work.

The second catch was that I couldn’t be bothered to prepare an appropriate software infrastructure for just a test.

Third catch, the network was a bit complex so I couldn’t just use directly VLC.

I wanted a one line solution. I knew that ffmpeg could save the IP camera stream to a file and I knew that VLC could stream a file wherever I wanted.

One line solution that mostly worked for me:

ffmpeg -hide_banner -loglevel panic -i rtsp://192.168.0.2/onvif2 -codec copy -f matroska - | vlc - --intf=dummy --sout '#rtp{sdp=rtsp://192.168.2.1:5050/test.sdp}'

Your mileage may vary, but I think it is a good starting point. It worked on a CentOS 7, ffmpeg 3.4.7, VLC 3.0.8

A.C.

Posted in Software | 1 Comment

Happy 2020!

Happy New Year to everybody.

The last nice round year is another year nearer. There is hope I’ll see it, a real privilege as the last one was a long bit ago while the one after the next one is really a long way into the future.

So, if everything goes according to the plan, I will get to see it together with you, dear readers, something that I think the majority of mankind didn’t see and will not see.

By the way, I am actually also headed to my probably last, nice, round birthday which is happily nearer than 2048.

A.C.

Posted in Uncategorized | Leave a comment

Solartron 7150 added to the stack

Solartron 7150

Solatrton 7150

Now the trio of my 5.5 digits or better DMMs is working and logging which means I am out of IEEE 488 cables which means I ordered two more as there is a lot of my equipment that is really asking to be connected to a NI GPIB card.

Just a little something about the Solartron 7150: the front inputs and the back inputs are in parallel so you have to be somewhat careful of what are you doing. It is my understanding that the Solartron 7150W adds a pushbutton so you can switch between front and back inputs. There is also a Solartron 7150plus with better input impedance.

A.C.

Posted in Analogic, Digital, Electronics, Equipment, Hardware | Leave a comment

HP 3456A & HP 3457A

HP3456A HP3457A

Top HP 3457A
Bottom HP 3456A

I am not dead yet, just very tired. This photo is just to show that something is happening on the DMM side of things.

As soon as possible, I want to write about linux-gpib, DMM and logging.

A.C.

Posted in Analogic, Digital, Electronics, Equipment, Hardware, Photography | Leave a comment

HP 5300A/5302A

This basic counter came with a lot of equipment I purchased some time ago. I didn’t need another counter but I wasn’t going to complain of getting another piece of test equipment.

Anyway, when I turned it on it didn’t count anything.

The real counter is the upper unit (5300A) while the lower unit is the signal conditioning unit. The two units easily snap together (like the Model 3470 Measurement System) and so it is really easy to disassemble.

I took a look at the pcbs but there was nothing that seemed to be broken/burnt/missing.

I expected that it would have been fun to poke around the counter but it wasn’t meant to be as inside there is a slider switch with two positions: INT and EXT. On the EXT position, the counter expects a timebase on its read BNC connector while on the INT position we get the internal timebase on the BNC connector.

As you can guess, it was on the EXT position while it should have been on the INT position.

That’s it.

A.Cicuta

 

Posted in Electronics, Equipment, Hardware | Leave a comment

HP/Compaq 2510p: changed DC power connector

I rather like my HP/Compaq 2510p so I have been really displeased when the laptop suddendly powered off even if it was attached to its power supply. The fact that I recently bought a new battery for it only added to my displeasure.

The first thing I checked was the power supply… which was dead. This sent me to a wild goose chase as I bought a new power supply which didn’t work, returned it, bought another one which worked but the laptop stubbornly refused to turn on.

Therefore I decided to dissect. On the HP site you can find the user and service manual so disassembling the laptop is not really easy but feasible (my keyboard was stuck in place and I had to apply more force that I would have liked to free it).

In the end, the DC power connector had a broken pin. I decided to buy a new one instead of just touching up the old power connector with a bit of solder.

As motherboards are cramped and the ground place is usually really good soldering on it is not the easiest thing to do but the old connector went out and the new connector took its place.

Now the 2510p works as it should.

A.C.

 

Posted in Electronics, Equipment, Hardware, Repair | Leave a comment

Merry Christmas 2018

Like I wrote in the title, Merry Chirstmas 2018.

A.Cicuta

Posted in Uncategorized | Leave a comment