Archive for the ‘TCF 2011’ Category

LAMP Servers for the big boys…

Saturday, April 9th, 2011

For those of you with a P4 class machine the best solution is a real OS like CentOS. It has a longer life cycle than Fedora and is so easy to add packages to. My favorite P4 is the ShuttlePC These are available in many different configurations and as 1 AGP and 1 PCI slot on the back. I also have a Revo. It does have HDMI out for video but works well with a DVI to HDMI adapter cable and an old Dell monitor. You could call it a netbook with no screen. I haven’t really found a good use for this yet other than BOXEE


One Linux package I would highly recommend is Midnight Commander. Its a clone of the old Norton Commander with some really neat new tricks.

Just type “yum install mc” at a command prompt and it will do the rest  Type “mc” to get started. If your functions keys wont work you can always user “esc” number instead. Hit “Esc” then “2” for the F2 menu or “esc” then “0” for f10 or exit. It works really well on a SSH session from a remote location and can even bring   up other machines in the view panes using SSH or FTP

Good Embedded Servers

Saturday, April 9th, 2011

I got asked a few questions about LAMP servers. Here are some of my favorite machines to use if you dont have a lot of space or power. Most of these are Pentium I Class machines unless noted otherwise.

The IBM Netvista 2200 I have a bunch of these used as Digital Signage and Media Players. They are very hard to make an OS for but if you Google Netvista 2200 Linux you will find one site with all you need. They dont have a real bios as a pc would have and only like to boot a specifically formatted kernel. These aren’t really suitable for running a backend database.They do need an external 12V power brick.


Then there is their bigger brother the IBM Netvista 2800. These are great for almost anything. They have a real bios and can run Dos apps pretty well.  They will also run mos flavors of Linux and I even had on loaded with Windows 98se on a 4GB microdrive. To make that microdrive fit in the CF slot required removing the top side of the CF connector. All I did was clip the top corners with a pair of cutters and fold the side over. It snapped off cleanly. I’ve done this to to a half dozen or so and never broke and thing. YMMV. I like the fact that the power supply is built in and it has pc standard serial and parallel ports and 2 PCI slots. These make great firewalls or VOIP PBX machines.


When you really want horsepower there are plenty of small form factor (SFF) pc’s out there with P4 or better processors. In the top of this pic is a 2.4Ghz P4 Netvista box and the bottom is a 2.8Ghz P4 SFF machine many of these lack space for  PCI cards even thought he motherboard will have the slots. The big Netvista has a few half height PCI slots. The middle machine is a Wyse thin client. That’s a whole different story, or at least paragraph.


I have tried many different thin clients and the HP are the best so far for my needs. The Wyse shown above is an oddity. It has a single PCI slot, a DVD and HD but is a Fat Thin Client. I like it but its external power brick gets in the way at times. The HP’s have no expansion and limited resources but can boot from a USB key so its easy to boot Linux and backup your work. I have many of these with FreeDos, DSL Linux and even one with Askozia PBX. They do run MySql pretty well but I use Monkey Web Server instead of Apache.


If you get the newer version it has a removable cover on the case that hides 2 USB slots. These can be used to hide Pen Drives and will be locked in by a standard PC cable restraint lock.

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Midi Sniffer

Tuesday, April 5th, 2011

This is the Midi Sniffer. It’s a little bigger than an old fashioned pager

 a5.JPG         a4.JPG

It has  a  Midi In, Power and Clear switch. Really didn’t need anything else.

a1.jpg  Power up notice

a2.jpg  Data from moving a CC Slider

a3.jpg  Hitting the Play button

Pretty Cheap and simple with just over a dozen parts.

  1. 16X2 LCD Display
  2. Pic 16F73
  3. 4mhz Crystal
  4. 2 – 22pf Capacitors
  5. 220 ohm resisitor
  6. 3 – 1K resistors
  7. 5K Trimmer
  8. OPTO Coupler
  9. DIN Jack
  10. Power Jack
  11. Clear Switch
  12. Pactec Case

I didn’t bother to make a PCB for this since its a one off project for a specific need I had at that time. Ill draw up a schematic and I already posted the Source and Hex files on my main site. I ended up removing the LCD routines and reused the code for the Midi Controller. That one will get a real PCB since I have plenty of uses for it.

P&T Surplus

Tuesday, April 5th, 2011


In case you looked at that P&T Surplus link and think thats all there is, well, no.

They have everything from key chains to a Jet Engine. They have a great robotic Arm Labeled “Igor”. I really want it but it must weigh about 2500 pounds. They had a nice servo motor driven XY table and even some Dragon Sculptures.

I’ve picked up circuit board cases, delrin scraps, rubber feet, suction cups, relays, magnehelics, vacuum gauges, electrical meters and all with single digit price tags.

Someone called it Canal Street from the 70’s but in Kingston NY

They were so right and I am grateful to them for turning me on to this place.

Light Dimmer Control using a Triac

Tuesday, April 5th, 2011

I mentioned using the PWM output to control a LARGE load with a Triac and someone asked what other parts you need so here is the circuit needed.


I have an electrical box with 3 of these circuits inside. That way I can keep it separated from the low voltage PIC. With proper heat-sinking and part selection 1200W Halogen lights are not a problem. It is optically isolated from the PIC but remember if your using PWM you may generate a lot of noise with a long cable run to the control head.


I got a nice heat sink electrical box combo from P&T Surplus for $10. If you’re ever in Kingston NY its a must see shop. Old dead PC power supply cases also make nice enclosures and can usually be had for free from your neighborhood trash bins or techie.

Trenton Computer Festival (TCF) 2011

Tuesday, April 5th, 2011

This year was a little different for TCF. The last couple of years I spoke about the EV project at school. Since that project has been mostly about getting a motor mount created  and not really computer related I decided to still speak this year but this time share the different uses for PIC micro-controllers I came up with over the last few decades….

I had so many topics I really had to cut it down to a few. I had some people really interested in using these things and I hope to hear from them. I have some videos from the actual talk and a couple of things I didn’t get to show.

I really wanted to do some Android apps but I didn’t have a chance. I did get to show 3 Iphone / Ipad apps. I have some stuff made with Titanium Developer but I was about to give up on Apple because of the store policies.

A new project idea was hatched at work last week that will make me revisit Apple again but I’m not as enthusiastic about them now that I have an Android tablet.

I think I’ll start with the one I didn’t get too. The Midi Sniffer…..

There are plenty of resources on my main site: