Power LED for original Inty?

[nightglider1]

I've got an original Intellivision console, and it's next to impossible (with my vision) to determine the position of the power switch past about 12 inches.

 

Does anyone have instructions on how I can wire a green LED (well, that seems to be an appropriate color to indicate "on") so I can tell at a glance if I left the power on?

[jaybird3rd]

It's pretty easy to do. The INTV System III had a red LED between the power and reset switches. It was just an ordinary-looking LED wired directly to the +5V and GND pins on the cartridge port (I don't happen to remember which pins). Since the operating voltage of most LEDs is 2.2V-2.4V, this must have been an LED with an integrated resistor; don't try to connect a regular LED directly to this pin or it will burn out! Here is a picture of the LED on my System III console:

 

 

Just drill a 1/4" hole in that spot, and use a Radio Shack LED holder (part number 276-079) with a T-1-3/4 (5mm) LED, and you'll have an exact replica. INTV used hot glue on the inside of the console to seal the LED and holder into place.

 

Be sure you know the specifications of the LED you plan to use. If you use a regular green LED (like this one), with a 2.2V operating voltage and a 10mA maximum current, you'll also need a 330-ohm resistor between the +5V power supply and the LED; some LEDs have a 20mA maximum current, in which case you'll only need a 150-ohm resistor. The resistor is necessary to bring the current down to a safe level. Here is the online calculator I'm using to compute the resistance values; they also show a wiring diagram and the resistor color codes.

[nightglider1]

Thanks, man -- I appreciate the help!

[nightglider1]

So, I've found the following pin details for Intellivision Cartridges:

 

 

 

 

If I'm reading these correctly, then if I look into the cartridge slot on my Intellivision the +5 volt pin is the lower right pin, and a ground pin is just above it.

 

Please let me know if I'm off base on this.

 

Thanks!

 

-- Pete

[GroovyBee]

This component overview shows where various voltages can be picked up :-

 

http://www.kohtz.com/andrew/intv_sm/page17.html

 

You need TP2 (+5v) and TP1 (GND). Depending on your soldering skill (ie lack of) you might also look at hooking TP4 instead. However that's 16v (unregulated) so you'll need to adjust your LED's resistor accordingly.

[nightglider1]

This component overview shows where various voltages can be picked up :-

 

http://www.kohtz.com/andrew/intv_sm/page17.html

 

You need TP2 (+5v) and TP1 (GND). Depending on your soldering skill (ie lack of) you might also look at hooking TP4 instead. However that's 16v (unregulated) so you'll need to adjust your LED's resistor accordingly.

 

Awesome -- tapping off of the PSU board will be much easier than tapping off of the cart slot. Thanks, GroovyBee!

 

My plan is to use some 18-20 gauge stranded wire with a connector from the PSU board, and have the matching connector attached to the LED/resistor combination with another length of wire. That way, if I need to disassemble the console again, the connector can be separated so as not to tie the console lid to the internals.

Edited September 15, 2010 by nightglider1

[GroovyBee]

My plan is to use some 18-20 gauge stranded wire with a connector from the PSU board

 

Single strand wire will be better then you don't have to worry about "whiskers" shorting things out.

[nightglider1]

My plan is to use some 18-20 gauge stranded wire with a connector from the PSU board

 

Single strand wire will be better then you don't have to worry about "whiskers" shorting things out.

Thanks for the advice. I think I even have some red and black "bell wire" hanging around in the basement. The less I have to buy, the better!

[nightglider1]

I've recently obtained a console which is working flawlessly, so I'm going to experiment with this on my flaky console first.

[GroovyBee]

Thanks for the advice. I think I even have some red and black "bell wire" hanging around in the basement. The less I have to buy, the better!

 

Yep! Bell wire should do nicely. If your soldering skills aren't too good then unsheath about an inch of wire from one end and form it into a hook shape at the bare wire's mid point. Hook it around the leg of the capacitor/regulator and then pull the exposed wire end tight with pliers and twist it together to form a "screw thread". That'll be easier to solder. Make sure its not touching anything else tho.

[nightglider1]

If your soldering skills aren't too good then unsheath about an inch of wire from one end and form it into a hook shape at the bare wire's mid point. Hook it around the leg of the capacitor/regulator and then pull the exposed wire end tight with pliers and twist it together to form a "screw thread". That'll be easier to solder.

I have moderately decent soldering skills, but I plan on doing it this way anyhow. Until I grow that third arm, I'll take every advantage I can get!