Resistors: Color code training for electronics technicians and repairers

[Andreas Thaler]

Anyone who deals with older electronic devices and cameras (e.g. Canon AE-1) will find wired resistors with colored rings. These rings give the resistance value, the tolerance and, if necessary, the temperature coefficient.

Those who are experienced can read the codes directly, everyone else uses tables or apps.

The TU Berlin offers a nice online training tool free of charge for reading the color codes:

Projektlabor-Onlinekurs – Widerstandsringspiel zur E12-Reihe – Leicht

The language is German but I think dealing with it comes naturally. Simply select the level of difficulty, enter the value read of the shown resistor and you will receive feedback whether it is correct or incorrect.

Ideal for the time between projects to stay fit

The color codes should be internationally valid.

Electronic color code - Wikipedia

en.wikipedia.org

 

[Chan Tran]

Anyone who deals with older electronic devices and cameras (e.g. Canon AE-1) will find wired resistors with colored rings. These rings give the resistance value, the tolerance and, if necessary, the temperature coefficient.

Those who are experienced can read the codes directly, everyone else uses tables or apps.

The TU Berlin offers a nice online training tool free of charge for reading the color codes:

Projektlabor-Onlinekurs – Widerstandsringspiel zur E12-Reihe – Leicht

The language is German but I think dealing with it comes naturally. Simply select the level of difficulty, enter the value read of the shown resistor and you will receive feedback whether it is correct or incorrect.

Ideal for the time between projects to stay fit

The color codes should be internationally valid.

Electronic color code - Wikipedia

en.wikipedia.org

If a resistor is in good condition simply measure it would be easy. If the resistor is damaged mostly due to overheating the color may be very difficult to make out.

 

[bernard_L]

If a resistor is in good condition simply measure it would be easy.

If in situ (soldered in a circuit) a real measurement is not possible.

 

[Alan Edward Klein]

Anyone who deals with older electronic devices and cameras (e.g. Canon AE-1) will find wired resistors with colored rings. These rings give the resistance value, the tolerance and, if necessary, the temperature coefficient.

Those who are experienced can read the codes directly, everyone else uses tables or apps.

The TU Berlin offers a nice online training tool free of charge for reading the color codes:

Projektlabor-Onlinekurs – Widerstandsringspiel zur E12-Reihe – Leicht

The language is German but I think dealing with it comes naturally. Simply select the level of difficulty, enter the value read of the shown resistor and you will receive feedback whether it is correct or incorrect.

Ideal for the time between projects to stay fit

The color codes should be internationally valid.

Electronic color code - Wikipedia

en.wikipedia.org

When I was in the USAF in the 1960 learning electronics, we learned this to remember the color code number equivalents.

Bad Beer Rots Our Young Guts But Vodka Goes Well
There was a dirty one as well, but I don't think it's appropriate to post here

Numerically the value (0-9) of a resistor via the color-coded bands:
Black (0), Brown (1), Red (2), Orange (3), Yellow (4), Green (5), Blue (6), Violet (purple, 7), Gray (8), and White (9)

 

[Alan Edward Klein]

Interestingly, the USAF tested you for color blindness before entering and wouldn't allow you to be in electronics if you were.

 

[Andreas Thaler]

When I was in the USAF in the 1960 learning electronics, we learned this to remember the color code number equivalents.

You've seen all those sleek silver jets and their test pilots?

 

[Alan Edward Klein]

I just remembered tolerances. gold= 5%; silver=10%; and nothing I think was 20%

 

[Alan Edward Klein]

You've seen all those sleek silver jets and their test pilots?

Nah. I was never on a USAF plane except on Armed Forces Day like the rest of the tourists.

 

[Andreas Thaler]

Nah. I was never on a USAF plane except on Armed Forces Day like the rest of the tourists.

But as an electronics engineer, you maybe had cockpits as a topic, with their analogue displays and electromechanical controls?

The cockpit of the McDonnell Douglas F-4 Phantom II, flown by Lt. Col. Ron "Elvis" King of the 82nd Aerial Target Squadron Detachment 1, when he led the final military flight of the storied aircraft at Holloman AFB, N.M., Dec. 21, 2016. The F-4 Phant

Download this stock image: The cockpit of the McDonnell Douglas F-4 Phantom II, flown by Lt. Col. Ron Elvis King of the 82nd Aerial Target Squadron Detachment 1, when he led the final military flight of the storied aircraft at Holloman AFB, N.M., Dec. 21, 2016. The F-4 Phantom II entered the...

www.alamy.com

 

[koraks]

If in situ (soldered in a circuit) a real measurement is not possible.

Yeah, although it depends on the circuit. Without knowledge of the particular circuit, a measurement can indeed not be trusted to determine the value. It'll still say something, but that's another story.

 

[Sirius Glass]

I just remembered tolerances. gold= 5%; silver=10%; and nothing I think was 20%

Gold 1%
Silver 5%
Nothing 10% or as we said a Hughes Aircraft, "Good enough for Government work."

 

[Sirius Glass]

If in situ (soldered in a circuit) a real measurement is not possible.

Correct, to understand the measured value in situ one would need to derive the Thévenin equivalent circuit.

Thévenin's theorem - Wikipedia

en.wikipedia.org

 

[Anon Ymous]

Gold 1%
Silver 5%
Nothing 10% or as we said a Hughes Aircraft, "Good enough for Government work."

Alan is correct, 1% would be a brown band. No band would be 20%.

 

[Sirius Glass]

Alan is correct, 1% would be a brown band. No band would be 20%.

I will go sit in the corner now.

 

[mshchem]

I haven't used this since a junior high electronics class.

 

[Dan Daniel]

Interestingly, the USAF tested you for color blindness before entering and wouldn't allow you to be in electronics if you were.

I used to assemble video systems for editing, broadcast, etc. A new guy started and I was checking his work and found everything miswired. Which was strange because he was in school as an engineer and was a smart guy. Turns out he was colorblind! We made him a board with samples of every cable, splayed out with text labels for each color wire. With this, everything went smooth. I think that there are different types of colorblindness but his at least meant that if you told him a particular color was, say, red, everything got wired up fine.

 

[Andreas Thaler]

I used to assemble video systems for editing, broadcast, etc. A new guy started and I was checking his work and found everything miswired. Which was strange because he was in school as an engineer and was a smart guy. Turns out he was colorblind! We made him a board with samples of every cable, splayed out with text labels for each color wire. With this, everything went smooth. I think that there are different types of colorblindness but his at least meant that if you told him a particular color was, say, red, everything got wired up fine.

Touching

 

[Truzi]

When I was in the USAF in the 1960 learning electronics, we learned this to remember the color code number equivalents.

Bad Beer Rots Our Young Guts But Vodka Goes Well
There was a dirty one as well, but I don't think it's appropriate to post here

Numerically the value (0-9) of a resistor via the color-coded bands:
Black (0), Brown (1), Red (2), Orange (3), Yellow (4), Green (5), Blue (6), Violet (purple, 7), Gray (8), and White (9)

I learned the "dirty" one in a high school electronics class

..., "Good enough for Government work."

A coworker told me that phrase was once considered high praise, as Government specs were precise.

 

[chuckroast]

I learned the "dirty" one in a high school electronics class

I learned the inappropriate one first as well There are many other, more
sanitized ones here - we can't have people getting triggered and sobbing in the corner:

List of electronic color code mnemonics - Wikipedia

en.wikipedia.org

A coworker told me that phrase was once considered high praise, as Government specs were precise.

Yabut govt spec also was way OVER specified. I heard this story years ago ...

In the early days of integrated circuits, the govt specified that certain chips should be ceramic encapsulated so that they could be sent to space and be more protected against cosmic radiation (in theory, anyway).

The chips exhibited an unusually high failure rate. When disassembled, it was discovered that the little gold wires between the actual chip and the external pins of the package were breaking. Why? Because the thermal coefficient of expansion/contraction for the external packaging was significantly different than the wires which broke when the chip exterior expanded sufficiently.

 

[Andreas Thaler]

The cockpit of the McDonnell Douglas F-4 Phantom II, flown by Lt. Col. Ron "Elvis" King of the 82nd Aerial Target Squadron Detachment 1, when he led the final military flight of the storied aircraft at Holloman AFB, N.M., Dec. 21, 2016. The F-4 Phant

Download this stock image: The cockpit of the McDonnell Douglas F-4 Phantom II, flown by Lt. Col. Ron Elvis King of the 82nd Aerial Target Squadron Detachment 1, when he led the final military flight of the storied aircraft at Holloman AFB, N.M., Dec. 21, 2016. The F-4 Phantom II entered the...

www.alamy.com

Has anyone an idea where to find information regarding cockpit electronics of those days?

Countless discrete electronic components and cables must be installed behind the instruments.

Fascinating!

Were there computers in fighter planes in the 1960s?

 

[chuckroast]

Has anyone an idea where to find information regarding cockpit electronics of those days?

Countless discrete electronic components and cables must be installed behind the instruments.

Fascinating!

Were there computers in fighter planes in the 1960s?

There were certainly some version of computers on aircraft carriers and early versions of fighter target acquisition systems of the day. They may have be analog or hybrid, I don't know. The big contractors of the era were companies like Ratheon, Hughes Aerospace, Fairchild, Boeing, McDonald Douglas and the like. Certainly, by 1968, computers built out of discrete chips were in use. See:

Computing

 

[Alan Edward Klein]

But as an electronics engineer, you maybe had cockpits as a topic, with their analogue displays and electromechanical controls?

The cockpit of the McDonnell Douglas F-4 Phantom II, flown by Lt. Col. Ron "Elvis" King of the 82nd Aerial Target Squadron Detachment 1, when he led the final military flight of the storied aircraft at Holloman AFB, N.M., Dec. 21, 2016. The F-4 Phant

Download this stock image: The cockpit of the McDonnell Douglas F-4 Phantom II, flown by Lt. Col. Ron Elvis King of the 82nd Aerial Target Squadron Detachment 1, when he led the final military flight of the storied aircraft at Holloman AFB, N.M., Dec. 21, 2016. The F-4 Phantom II entered the...

www.alamy.com

I was a cryptographic technician. Never got out of the communications center.

 

[Alan Edward Klein]

Yeah, although it depends on the circuit. Without knowledge of the particular circuit, a measurement can indeed not be trusted to determine the value. It'll still say something, but that's another story.

We used to unsolder one lead and then take a measurement.

 

[Alan Edward Klein]

Gold 1%
Silver 5%
Nothing 10% or as we said a Hughes Aircraft, "Good enough for Government work."

I may be wrong, but back when I was doing these, it was 20%. This chart infirns the 5% and 10% for gold and silver but it seems to depend on the resistor type.

Decoding the Color Bands on Resistors: A Comprehensive Guide

Anyone working with circuit boards needs to know how to read resistors’ resistance values to prevent errors such as burned-out LEDs or microprocessor overheating. Today, color codes on resistors follow the international standard in IEC 60062, but that wasn’t always the case. In the 1920s and...

partstack.com

 

[koraks]

We used to unsolder one lead and then take a measurement.

That's a perfectly fine method if its mechanically feasible.