Repairing a USB keypad

[Daniel Prince]

I have a USB keypad with a broken cable. The cable is very thin (number 22 or smaller). I want to replace as much of the cable as possible with a USB device cable. My problem is that I do not know how to tell which of the wires in the device cable to connect to the two wires that go to the keypad.

I have not yet cut into a device cable but I think there would be four or five wires in the cable. How do I tell which of those wires I need to connect to the two wires that come from the keypad. I have some digital volt ohm amp meters and know how to use them.

The two wires in the keypad are the same color and connected together but they can be easily pulled apart. (I think this type of cable is called a zip cable. It is similar to a flat extension cord but MUCH smaller.) The keypad has a LED that lights up when it is in numeric mode.

The keypad is one of these:

|66%3A2|39%3A1|240%3A1318|301%3A0|293%3A1|294%3A50

Thank you in advance for all replies.

-- Whenever I hear or think of the song "Great green gobs of greasy grimey gopher guts" I imagine my cat saying; "That sounds REALLY, REALLY good. I'll have some of that!"

[Daniel Prince]

I have a USB keypad with a broken cable. The cable is very thin (number 22 or smaller). I want to replace as much of the cable as possible with a USB device cable. My problem is that I do not know how to tell which of the wires in the device cable to connect to the two wires that go to the keypad.

I have not yet cut into a device cable but I think there would be four or five wires in the cable. How do I tell which of those wires I need to connect to the two wires that come from the keypad. I have some digital volt ohm amp meters and know how to use them.

The two wires in the keypad are the same color and connected together but they can be easily pulled apart. (I think this type of cable is called a zip cable. It is similar to a flat extension cord but MUCH smaller.) The keypad has a LED that lights up when it is in numeric mode.

The keypad is one of these:

Thank you in advance for all replies.

-- Whenever I hear or think of the song "Great green gobs of greasy grimey gopher guts" I imagine my cat saying; "That sounds REALLY, REALLY good. I'll have some of that!"

[Oren]

Call the company that made the pad and ask for the USB pinouts.

Something like this:

[HeyBub]

|66%3A2|39%3A1|240%3A1318|301%3A0|293%3A1|294%3A50>

The one to which you point us is less than two dollars.

[Meat Plow]

Most usb are color coded red green white and black. Should be plenty of data if you go to google and enter 'usb wiring' as a search.

[Daniel Prince]

There are two wires coming out of the keypad. They are both black.

-- I don't understand why they make gourmet cat foods. I have known many cats in my life and none of them were gourmets. They were all gourmands!

[IanM]

The USB standard calls for four wires. It CANNOT work with only two. Take a really close look at the end of the broken cable. Each of what you think are the wires is just the outer insulating jacket over a pair of wires. You may need to trim back the jacket a bit to expose the wires enough to see them. When you have found the four wires, assuming they are colour coded, trim back the end of the half of the lead with the USB plug, and open the keypad and reconnect it, matching the colours. If they aren't colour coded, you are SOL so forget about it!

[Daniel Prince]

You are correct, after I trimmed back the insulation, I used my 30 power microscope. I could see two wires inside each tiny cable. There is no possibility whatsoever that I could solder those microscopic wires. I will just have to wait until the replacement keypads I ordered arrive from Hong Kong.

-- I don't understand why they make gourmet cat foods. I have known many cats in my life and none of them were gourmets. They were all gourmands!

[Stormin Mormon]

What the modern home needs, in the 1950s. Radar range, black and white television, and 30x binocular inspection microscope.

[Daniel Prince]

Actually it is a cheap monocular microscope. I bought it many years ago a Radio Shack. It is hard to use because it reverses the image.

-- I don't understand why they make gourmet cat foods. I have known many cats in my life and none of them were gourmets. They were all gourmands!

[Meat Plow]

USB has voltage and data connections + and - and cannot travel across two wires unless this is something new.