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equivalent transistors? Answered

i need equivalent transistors for ac188 and ac187
and is bc548 equivalent to bc148
i couldent find equivalents on google


AC188 is a germanium device, so in certain applications, you can only replace it with a germanium device. Odds on though, it won't matter. Post the circuit if you can, and I can tell you what will work.

"equivalence" means "near enough not to matter" in these cases.


the circuit i am making is a multitone bell
the transistors act like a amplifier

sir gud am..am making a project,rain alarm system w/c requires 2 transistors bc 548 and tl 188..sad to know dt tl 188 s not available in our region..wt cud b d posible alternativ for it? pls help me sir..tnx..ds s my email,louie.sputnik@gmail.com

what i can use instead of transistor fqp27po6


4 years ago

what can I use instead of AC188 and AC 187?

When looking for things on the web, I find that Yahoo search does a better job than Google, presumably because Google is more money hungry than Yahoo and will give top ranking to the highest bidder... Anyway, I did a search and the top link gives you equivalents: Search Here. Yes, BC548 will work.

Next, look up AC187/AC188. They are complementary NPN/PNP Germanium transistors. Look at the specs and then go to MCM Electronics and look for the Germanium transistors they have in stock (yes, they have Germaniums, I bought 2N404's a couple of months ago) and see what they have that is close. IF you cannot find them, you will have to use something close in the Silicon type and change the circuit to get it to work similarly (yes it can be done).


I usually use:
for looking up unknown part numbers.

The data sheet I found
says these are germanium small signal transistors.  The AC187 is NPN, and the AC188 is PNP.

Note that germanium BJT transistors are kinda rare compared to the more common silicon variety.   I'm not sure why this is the case, but maybe Wikipedia could help answer that one:

Do you know what these components are?
e,g, "general purpose NPN transistor", ought to find several. "high speed switching" etc.