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Author Topic: new MJE 350 transistors in kits  (Read 6487 times)

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Offline Doc B.

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new MJE 350 transistors in kits
« on: June 28, 2010, 01:32:59 PM »
The great parts famine of 2010 has forced us to look for substitute parts for many of the kits we manufacture. These substitute parts are of equal or better quality, but some look rather different than the original parts we used in producing the assembly manual. The latest case is one that will cause some confusion -

For the past 14 or 15 years we have used MJE 350 transistors that have a "front" black plastic side with the MJE 350 designation printed on it. The other, "back" side of the transistor is metal.
The current batch of Fairchild transistors we purchased do not have a metal side. One side is printed with the MJE 350 designation, and this corresponds to the "front" side of older transistors. It can also be identified by the three small dots imprinted in the plastic around the center hole. The "back" side, that corresponds to the metal side on the old transistors, has a more matte finish with no printing except for one small dot impression.
Dan "Doc B." Schmalle
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Bottlehead Corp.

Offline Wanderer

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Re: new MJE 350 transistors in kits
« Reply #1 on: November 22, 2010, 09:43:44 AM »
Knowing that if I can get something wrong I will. I read the above instructions and used a silver metalic oil based Sharpie to mark the "back" of the transistor so it became the "metal" side. 
Kevin R-M

Offline bgf

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Re: new MJE 350 transistors in kits
« Reply #2 on: November 22, 2010, 12:56:02 PM »
thanks i was just getting ready put this question to the forum.
brent fauss

Offline keithpgdrb

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Re: new MJE 350 transistors in kits
« Reply #3 on: October 30, 2013, 10:24:43 AM »
You should really fix this in the manual.  its just a pdf.  easy to do.  At the very least, post a picture of the correct orientation.

Offline Doc B.

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Re: new MJE 350 transistors in kits
« Reply #4 on: October 30, 2013, 10:46:52 AM »
We go through thousands of MJE350s in a year. As soon as we "fix" it we will probably get a shipment of MJE350s that have metal backs as shown in the manual, or some other appearance. This forum allows us to stay up to the minute with these changes as they occur.
Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.

Offline Paul Birkeland

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Re: new MJE 350 transistors in kits
« Reply #5 on: October 30, 2013, 11:01:18 AM »
You should really fix this in the manual.  its just a pdf.  easy to do.  At the very least, post a picture of the correct orientation.

There is a picture of the correct orientation, just look for the text.
Paul "PB" Birkeland

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Offline NightFlight

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Re: new MJE 350 transistors in kits
« Reply #6 on: November 29, 2013, 07:13:30 AM »
Is it just me, or am I missing something here? These transistor packages are ECB or BCE etc. They should be marked on the transistor package pin 1 as emitter. The PC boards I noticed are also marked. Even knowing about datasheets I neglected to refer to them due to the ever so simple PDF. Now I'm wondering if I didn't screw up the pin orientation.