"A" / "2SA" series Japanese datasheets?

[LucifersTrip]

I really thought it'd be very easy to find info on the common 2SA / 2SB / 2SC Japanese transistors, but it can be confusing.

Many times the "2S" is left out on the numbering on the plastic case silicon ones.

Here's the confusion:


This is clearly labeled as "A124", and you will see it listed in an inventory somewhere as "2SA124".  But, a "2SA124" is a metal case germanium.   This is clearly a plastic case silicon.

So, what are these plain "A" series silicon with low 3-digit numbers like the germaniums? What's a guess at when this "A124" was made?
...and can anyone find an actual datasheet for this?

thanx much

[Mark Hammer]

Sometimes these are house numbers, unfortunately, meaning that they are a number used for someone else's internal inventory needs.

Occasionally - as in the case of the EH1048, which we all understand to be relabelled CA3094 chips - the numeric equivalence to another device is broadly shared information.  Other times, not so much.  There used to be a huge, and I mean immense, book printed in little tiny letters on onion-skin paper, which provided a cross-listing of all known semiconductors, including house numbers.  Not sure if a similar listing exists now, some 25 years after the last one I saw.

[LucifersTrip]

In this case, it is not a house number. The A124 was from a Japanese seller...and it was advertised as 2SA124

At the time, the same seller had a full line of 2SA, 2SB, 2SC, etc...

...but there were these, which have the same number as the ge's without the "2S"

Is there a datasheet anywhere?

[Mark Hammer]

Here's what my databook says about it.  I've chopped the page just below 2SA124.

[LucifersTrip]

Here's what my databook says about it.  I've chopped the page just below 2SA124.

Thanx...though, this is the EXACT confusion I mentioned in my first post. I believe this is for the germanium 2SA124
http://www.datasheetarchive.com/dl/Databooks-1/52-27.pdf
http://transistor-spravochnik.ru/description/2sa124/7468

not, the A124 silicon (which, confusingly, is also listed as 2SA124 in some sale lists today)

I forgot to mention that my Peak Atlas shows the A124 as "PNP Digital" and does not show an hfe. With a quick search of PNP digital, they are listed as having built-in resistors


edit:
I think I finally found it.

This was a tough one....the A124 is listed side by side with probably what is a newer version, DTA124ES

It is a digital transistor. As I noted, my Peak Atlas does also show it as "PNP Digital"

I found a datasheet here:
http://www.datasheetarchive.com/dl/Datasheets-27/DSA-524494.pdf