How to test the TDK TBD420NR CCFL inverter

TDK TBD420NR inverter with some signal paths highlighted.

The TDK TBD420NR CCFL inverter is found in many laptop screens. I've found it in an HP Pavillon DV9500.

LCD screens with CCFL backlight are prone to failures and  you are often in doubt if it is an inverter or CCFL lamps failure.
So it is very useful to have a way to live check the inverter before ordering a new one just to discover that the failure is elsewhere.
I've found a way to live check the TDK TBD420NR.

Installing an HP OEM Windows 2012 R2 Essential server as KVM Guest

I have an HP Proliant DL385p Gen8 box together with a HP/OEM installation disk of Windows Server 2012 R2 Essential.
On the iron I've installed Ubuntu Server 12.04.5 64bit plus xfce 4.1 (horrible: avoid it!) and KVM latest version available in ubuntu repository at the time of this writing (Dec2014).
The windows server is going to run as a guest over KVM. I have plenty of configurations like this perfectly working where, however, the Windows software is not OEM..
Here, a little while after the windows server installation CD boots up in the guest, it stops with the following message:"This system is not a supported platform": the hardware platform must be an HP and the actual one is not. No way.

ARDUINO UNO as a USB to GPIB controller - version 6.1

TEK2232 loves Arduino

Fluke PM2534 loves Arduino

Disclaimer:
This program is provided as is. It is a hobby work.
It doesn't work correctly. It has not been tested. It can damage your Arduino and the device you connect it to.
Can have unexpected behaviors, can get stuck at any moment, can read and write data to/from the device in ways you might not expect. It can send wrong or erratic commands to the device. Can display data that differ from the actual data the device sent out. Can address GPIB devices differently from what you might expect.
I have not conducted any speed test; the maximum speed supported is simply unknown.
Is does not follow any official standard. Only a minimum set of the functions included in IEEE-488 is barely emulated.
Hardware limitations: the lack of a GPIB line driver has two major implications: first: your Arduino is directly connected to the device GPIB port without any form of electrical protection of buffering - this can potentially damage your Arduino and/or your device; second: what can happen if you connect more than one GPIB device to the BUS is unpredictable both from an hardware and software point of view. I only experimented with a single GPIB device connected to the BUS.

Arduino USB to GPIB firmware by E. Girlando is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Permissions beyond the scope of this license may be available at mailto:emanuele_girlando@yahoo.com.

After nights spent coding, this post is about version 6.1 of my USB to GPIB controller software for ARDUINO UNO.
Version 6.1 ??!! Yes, that's it! This is actually version 2 of my software, but because some third party software - actually KE5FX GPIB toolkit -  relies on the content of the output string as issued by the "++ver" command to work properly, I had to force the string "version 6." as part of the" ++ ver" command output. So .. this version has become version 6.1. 

Version 1.0 has been presented in this related post.
Version 1.0 was very crude. Most a beta version to verify the feasibility of this project.
I want to thank you very much all of you that provided me feedbacks.

Arduino UNO as a USB to GPIB adapter / controller

NOTE:
This version is OBSOLETE!! Please go to this post for the 6.1 release software and documentation.
---

Version 1 of this project is aimed to provide a cheap and quick GPIB solution to those that need to gain control over a single instrument and interact with it (e.g. to calibrate instruments that can be calibrated by GPIB only -- 6632A Power Supply being a good example).

I supposed that cheap adapters were available on the market to interface GPIB instruments with a PC. I was wrong. The only feasible solution is to go with a Prologix USB to GPIB converter, still it would have cost me some tens of bucks.
Other solutions required buying or building hardware.

On the other end I had an Arduino UNO floating around on my bench waiting for a problem to solve other than blinking leds or writing "hello world" on an LCD..

So I decided to face the challenge of writing down a c++ program and have the Arduino play the adapter role I was looking for.
To make a long story short.. (I supposed that GPIB was simple at least as much RS-232 is, .. and it is not! I was wrong again!) after reading a lot of IEEE-488 documentation and giving a try to a similar program I found over the internet, I got a decent implementation of a GPIB controller out of my Arduino UNO. This post is dedicated to describe the project.

How to defeat the standby circuit in the Seleco BS700 tv chassis

Some time ago my 14" Seleco TV started to exhibit a problem:
exactly 5 minutes (and when I say exactly 5 minutes, I mean exactly 300 seconds) after startup, it turn back to standby (here is a post about that here).

I 've found this problems is related to the processor's NVRAM (C.I.1 - NVM3060) that lost its content.
I managed to reprogam it (using the ponyprog programmer I have written a post about), but the solution wasn't definitive. After a while the NVM3060 lost its content again and the problem raised as before...

So, to get around the problem,  I decided to try to defeat the standby circuitry. I've requested help on some repair forum with no success, so I dived a little in the bs700 diagram. I was not able to fully understand how that circuit works, however I was able to realize that grounding Pin 16 of the TV processor should have done the job. And it does! This is what T1 and T2 manage to do depending on the various ORed conditions required to exit the standby mode (press P+ OR press P- OR command from the remote OR ...) . T1 in particular keeps pin 16 down to ground through R14 while the TV set is running.
A side effect of this approach is that every 300 seconds the screen flashes black for less than a second. This is due to the processor still trying to turn the tv in standby as the default sleep time times out; it's a command internally executed by the processor I cannot do anything about.

So the modification more than trivial as ground jumper is very close to R14. Just have a look at the following pics to see how I've made the connection.

Good luck with your bs700!
Emanuele.

Before

After