NTE Electronics, the well-known provider of the NTE123, NTE123A, and NTE123AP NPN transistor, has closed its doors. DigiKey no longer carries these components. Fortunately, many substitutions are available, allowing you to restore your vintage equipment.
Who was NTE?
NTE Electronics was a key provider of semiconductors for repair technicians. The company (Sylvania ECG at the time) was very important to my electronics journey. At the time, almost every small town had one or more TV repairmen. Each of them stocked NTE parts. This was an efficient system as a small number of NTE parts could replace semiconductors found in TVs and radios ranging from the 1950s to present. The NTE123X is a perfect example as this small-signal general-purpose transistor was the recommended substitute for thousands of devices.
The secret to NTE/ECG’s success was the printed catalog (later internet). I can still remember the smell and faded yellow tissue-thin pages of my first catalog. It was the mid-1980 when the local TV repairman handed me the 1-inch-thick catalog. It contained hundreds of small-print pages the cross-referenced parts back to the ECG substitutions. With that catalog in hand, I came to appreciate the nature of semiconductors and logic circuits.
Figure 1: Opening data from the NTE123AP datasheet.
Tech Tip: Japanese transistors that start with letters such as B772 or D882, are typically part of the 2S series. The full part numbers are 2SB772 and 2SD882, respectively. Note that B typically signifies PNP, while D signifies NPN. The NPN 2SBXXX was occasionally encased in green epoxy. There are similar conventions for the 2SAXXX (PNP) and the 2SCXXX (NPN).
Where can I find a NTE123, NTE123A, or NTE123AP?
Finding DigiKey substitutions for the NTE substitutions is an interesting question. After all, the NTE123X was a substitution of thousands of parts. We are asking what DigiKey parts are adjacent to the NTE123X.
Always remember that NTE’s secret sauce was its cross-reference catalog. They were not a parts manufacturer. Consequently, we should be able to work backwards from the NTE parts description to locate a suitable replacement.
Tech Tip: Rebranding is a common practice in the semiconductor industry. This can be done for beneficial reasons, as NTE rebrand parts from reputable manufacturers. It can be done for nefarious reasons resulting in counterfeit semiconductors with questionable reliability.
It turns out that the NTE123X family is a proud member of the Jellybean component club. Specifically, the NTE123X are rebranded 2N2222 NPN transistors. Likewise, the complementary NTE159 is a rebranded 2N2907 PNP transistor. Close inspection of the datasheets reveals nearly identical device characteristics with the same package type and pinout. The datasheets are like looking into a mirror—provided we choose the correct packaging.
We need to be careful as the NTE123 to NTE123AP appear to follow the same progression as the 2N2222 to a modern 2N2222A such as this Diotec Semiconductor example. The original 2N2222 and NTE123 featured a metal can TO-18 package as shown in Figure 2. The NTE123AP features the familiar JEDEC compliant TO-92 packaging.
Location within DigiKey
To locate replacements within the DigiKey system, we can perform one of two searches:
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NTE123 search “2222 BJT TO-18”
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NTE123AP search “2222 BJT TO-92”
Figure 2: Image of the Microchip (Microsemi) JAN2N2222A NPN transistor.
Period-appropriate replacements for vintage equipment
People who restore electronic equipment take pride in their work. Some will go the extra mile to perform the restoration with period-appropriate devices. Use of TO-18 packaged components such as shown in Figure 2 is an important consideration. Modern TO-92 components would look out of place.
Parting Thoughts
One final recommendation:
Trust But Verify!
Ultimately, you are responsible for the semiconductor substitutions. While I believe the NTE123X to 2N2222 recommendation is sound, we must recognize that there are millions of unique circuits, each with unique needs. The long chain of substitutions implied in the article may not work in all situations.
As a former DigiKey partner, NTE will be sorely missed.
Here’s to the legacy of the NTE123.
Best wishes,
APDahlen
Related Information
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About This Author
Aaron Dahlen, LCDR USCG (Ret.), serves as an application engineer at DigiKey. He has a unique electronics and automation foundation built over a 27-year military career as a technician and engineer which was further enhanced by 12 years of teaching (interwoven). With an MSEE degree from Minnesota State University, Mankato, Dahlen has taught in an ABET-accredited EE program, served as the program coordinator for an EET program, and taught component-level repair to military electronics technicians. Dahlen has returned to his Northern Minnesota home and thoroughly enjoys researching and writing articles such as this.