Transistors Difference

[oskar270]

The attached schematic indicates how to build an electromagnetic coil for a wooden clock I’m building. however my local store did not have the required 2N2222 transistor and they gave me a 2N222A.

Does it make a difference?

Thanks

 

[ljcox]

Did you mean 2N2222A? If so it is the same transistor. Virtually any NPN transistor should suffice provided it can handle the collector current.

 

[oskar270]

Thank you for your time Len

I was told at the store it is 2N222A but looking at it now with magnifying glass it says

KSP 2222A K3g

Should I test it and if yes how? I will be using 9VDC and my meter

 

[AnalogKid]

2N2222, 2N3904, 2N4401, etc. In your application, electrically identical. BUT - check the pinouts.

ak

 

[atferrari]

The schematic was listing also a 2N3???

 

[ljcox]

Does your meter have a transistor tester option?
Do you have a data sheet for the 2N2222? Also look search for the KSP 2222A . Compare their data sheets. I suspect it is identical to the 2N 2222A.
If not, you can download them from the internet.
Does your meter have a diode option?
If so, check the Base - Emitter junction & the Base Collector junction they should both measure the same as a diode. i.e about 0.6 Volt in the forward direction & open circuit in the reverse. (identify the C, B & E legs from the data sheet)
You could also rig up a simple test circuit using a 9 Volt battery & 2 resistors. Use what ever you have on hand for the collector resistor. A resistor between 1k & 10k would suffice. Connect the other end to the +9 Volt battery (& the emitter to the - terminal. Measure the voltage across the C & E. It should read about 9 Volt. Then connect another resistor (10 k ~ 33 k) between the B to the +9 V. The C voltage should drop to less than 1 Volt.
Do NOT connect the B directly to the +9V. Let me know how you go.

 

[oskar270]

Of course I’m aware with the pinouts, most important

Len my meter does not have a transistor or diode options. From the Internet I understand the 2222A is the newer version of the 2222 so I think I’m ok.

My collection of electronic supplies is very limited and unfortunately one of the 2 bridges (Ile Aux Tourtes Bridge) connecting my area to the Montreal island is closed indefinitely since yesterday afternoon. The traffic is diverted to a second smaller bridge and it took me today 4 hours to go and get the transistor. Since the electronics supply store is in Montreal I can’t go again to get the resistors required to complete the test you are suggesting. It’s much easier to complete the electromagnetic coil.

I ordered the 30g wire for the two coils thru Amazon and I should get it on Monday

My thanks to all

 

[crutschow]

The 2N2222a will be fine for you circuit.
You don't need to test it.

 

[unclejed613]

The schematic was listing also a 2N3???

the page is cut off... most likely a 2N3904