D1303 transistor data needed

Mjolinor schrieb:

...

"Your" 2SD1303 seems to be a bipolar transistor. Have a look at

HTH

Reinhard

two

centre

find

please.

Thanks for that but (there is allways a but) while looking for this I found the page you posted and I found

which suggests it is also an FET.

Hence the post :)

I sort of sketched out the circuit, a task I truly despise because if I do it five times I get five different circuits, but I think I am concluding bipolar NPN. I would appreciate some conclusive evidence for sure.

found

Does the part have a manufacturers name or trade mark printed on it? Japanese transistors are usually marked with the "2S" missing. For example, a 2SA419 would usually be marked as "A419" on the component.

My old Towers transistor book does not list a 2SD1303, but my Towers FET book does list a D1303... N channel, depletion mode, Junction FET. VDS: 25v. Id: 15mA. Ptot: 0.4W Replacements: BFW13, 2N3686.

From the drawing, it looks like the D1303 FET uses a small round metal case. Japanese 2SD transistors more commonly use plastic or TO3 style packages.

example,

case.

There are no other markings at all other than D1303. It's a plastic trapesium shape. I concluded NPN because all the biasing / signal resistors are

OK, I finally got off my f***ss, searched out my old database and re-installed it on one of the other systems.

A search for "D1303" brings up a 2SD1303: Plastic package, TO92. Looking at the flat side... _________ | | | | | 2SD1303 | | | |_________| | | | | | | e c b

NPN, 60v, 2Amp, 1Watt. Suggested equiv. 2SD1207

That's all it says about it, does it sound like what you have there?

Maybe :)

I stuck two same number NPNs in and got the scope out.

What I have is a two transistor configuration. The device will run from either 2 X 1.5V batteries or a 4.5 V power brick. This goes through a small ferrite transformer to the centre leg of one transistor (emitter?), one outside leg is grounded (collector?) and the other outside leg (base?) is fed from a big, square, multi leg thing out of which comes a square wave when you press "on". This makes the transistor middle leg (emitter) have a bigger square wave. I think what should happen is that the other transistor being part of this "two transistor/ferrite transformer oscillator thing" should develop a voltage at the collector that is greater than the input voltage and this closes the loop so then when you take your finger off the "on" button the square wave feed into traansistor 1 base doesn't stop. What I have is a DC at about half supply from the second transistor so I am thinking higher frequency transistors because the square wave stops when you remove your finger from the button. This thing is probably worth about £10 if working, it's wierd what gets your attention and why. There is no possible sensible reason for not putting it in the bin other than "why doesn't it work".

With an NPN device, I would suspect that this would be the supply to the collector.

Are you sure you don't mean emitter? The collector of an NPN transistor would not be grounded.

I would agree that this could well be the base.

With an NPN transistor, and your reading being from a scope, this is most likely the collector. For the output to be from the emitter, you would have an emitter follower stage - giving a lower voltage output.

These connections would fit the transistor pin data above.

It's probably about the challenge and not letting something beat you. I have often done such things.

(emitter?),

OK so I'm a pillock :) no change there then.

Yes the above is probably correct, I can't think and write at the same time which probably says I shouldn't post in newsgroups but I am afraid your stuck with me.