Need help with a rare MOTOROLA transistor 'TE 184' - Page 1
Forum section: electronics / repair

author: LvdK
author_rank: Newbie
timestamp: December 02, 2020, 09:35:35 pm
content: Hello, I need some help with an old Motorola TO3 power transistor.It has TE 184 and 423 written on the top and also you can see the Motorola logo on it.At the bottom side you can see a B and E inscription near the pins.I searched all over the web but I cannot find anything about this device...I desoldered it from an old transistor car ignition unit built around the year 1975 because I have to repair it.I analyzed the pcb and together with the B and E inscription I assume that it is a NPN type transistor. B-E shows no connection in both ways, so it is broken.Who can make me happy with some data of this transistorand perhaps also knows a good substitution type ? Thanks !

author: Leadfootin
author_rank: Contributor
timestamp: December 24, 2020, 02:10:23 pm
content: I would think this is used for an ignition system where the transistor replaces the points and if so the open E-B connection may point to further problems. As for the power transistor I would first try a 2N3055 but a recent production as this part has evolved quite a bit since the '70's. If a PNP try a 2N5884.One caveat is that this might be a darlington pair so check base emitter connection with at least 2 volts. If so the above recommendations won't work.Did you determine the cause of failure as the coil is most likely going bad unless the engine sat with the ignition on for a significant period without running.Additionally what make is the box, what engine is it on and is the distributor mag pick up or points or opto?

author: DC1MC
author_rank: Super Contributor
timestamp: December 24, 2020, 02:38:30 pm
content: I think 185 should replace it:https://www.ebay.com/c/697589595Cheers,DC1MC

author: grumpydoc
author_rank: Super Contributor
timestamp: December 24, 2020, 03:47:08 pm
content: Might this be the more modern equivalent?https://pdf1.alldatasheet.com/datasheet-pdf/view/9774/NTE/NTE184.html

author: CaptDon
author_rank: Super Contributor
timestamp: December 24, 2020, 06:02:07 pm
content: Was that from one of the old 'Mark' aftermarket ignition systems??A gold and silver box with one or two TO-3 devices on the top?That system had a power oscillator to build about 400vdc and an SCRto fire that voltage through the original equipment ignition coil. Minehad a switch on the side that would revert to conventional arrangementif the solid state ignition failed. I think you had to remove the condensorfrom the distributor? The NTE/ECG 184 is NPN and the 185 is the matchingPNP. Not sure which you may have. I had my unit on a '70 RoadRunner.That thing would throw over 2" sparks and you better have a good rotoror the excess high voltage would punch through it and short out to theshaft!!! The unit should make a whining sound as it charges the capacitorand a tick sound when it fires.

author: fzabkar
author_rank: Super Contributor
timestamp: December 24, 2020, 06:50:22 pm
content: Quote from: grumpydoc on December 24, 2020, 03:47:08 pmThat's a plastic package. The rating is only 80V.http://www.nteinc.com/specs/100to199/pdf/nte184.pdf

author: fzabkar
author_rank: Super Contributor
timestamp: December 24, 2020, 06:55:20 pm
content: Check the databooks for likely candidates:https://mirrorservice.org/sites/www.bitsavers.org/components/motorola/_dataBooks/Judging by the date code, I would start with 1974.https://mirrorservice.org/sites/www.bitsavers.org/components/motorola/_dataBooks/1974_Motorola_Discrete_Semiconductor_Series_A_Vol1_to_1N5000_2N5000.pdfhttps://mirrorservice.org/sites/www.bitsavers.org/components/motorola/_dataBooks/1974_Motorola_Discrete_Semiconductor_Series_A_Vol2_1N5000_2N5000_and_up.pdfhttps://mirrorservice.org/sites/www.bitsavers.org/components/motorola/_dataBooks/1974_Motorola_Discrete_Semiconductor_Series_A_Vol3_Non-Registered_Type_Numbers.pdf

author: LvdK
author_rank: Newbie
timestamp: December 31, 2020, 01:32:00 pm
content: Thanks for all your help guys !!Specially the Motorala databooks links mentioned by fzabkar are worth to consult !And also thanks to Leadfootin who made me realize that also a Darlington could have been be used.But still I cannot find this Motorola device...Is'nt it strange that a transistor of a well known brand as Motorola can't be found on the web ?For now I am going to try several NPN high voltage transistors with TO3 case.Thanks !

author: fzabkar
author_rank: Super Contributor
timestamp: December 31, 2020, 05:33:36 pm
content: It could be a custom device for a particular customer, or it may be just a relabelled version of a standard part.Edit:See page 84 for a circuit diagram of a transistor assisted ignition kit (from 1977):https://worldradiohistory.com/Archive-Electronics-Today/Australia/70s/ETI-1977-05-May.pdfNote that CDI (capacitor discharge ignition) is a different technology that was also available at that time.

author: ralf
author_rank: Newbie
timestamp: February 13, 2021, 09:00:47 pm
content: Busch Jaeger CDI? Had success replacing this transistor by a BUX98A type and adding a protection diode...

author: rfclown
author_rank: Frequent Contributor
timestamp: February 13, 2021, 09:30:20 pm
content: Quote from: fzabkar on December 31, 2020, 05:33:36 pmI worked at Moto in 1986. We had custom part numbers for Motorola transistors for our land mobile radio products. Sometimes these were common parts, but that was not published information (not even internally). I remember when I found someone who had a cross reference for several internal vs standard part numbers (hand written on a piece of paper). It was golden information. The person that originated it may have just guessed from specs. I was in development engineering, and we weren't supposed to know these things.

author: LvdK
author_rank: Newbie
timestamp: February 16, 2021, 04:20:55 pm
content: Quote from: ralf on February 13, 2021, 09:00:47 pmYes it is a Busch Jaeger CDI. So thanks for the information !

author: CaptDon
author_rank: Super Contributor
timestamp: February 18, 2021, 02:55:09 pm
content: Motorola was always a BIG player in the 'house-numbering' of parts for its customers advising them to do this in an effort to protect intellectual property. I have run across so many house numbered motorola parts that it made me turn away from motorola products completely!!! No motorola pagers, two-ways, etc. etc. At least with Tektronix and others like Peavey you can guess what the 'real' number should be, a TEK741 is a hand selected LM741 a Peavey T2222 is a 2N2222A. Motorola made the JEDEC parts since that was a military requirement of second sourcing. But, they also house numbered the exact same parts for consumer manufacturing with no cross reference available back to the JEDEC part. Why, because they charged about 10 times as much for the JEDEC 'militarized' parts which were simply run-of-the-mill parts tested and proven to meet worse case specifications!