# Sub for 2SC732



## K Pedals (Jul 15, 2019)

Does anybody know a substitute for the 2SC732s??? I’m trying to build an uberdrive...


----------



## the_grumpy_gnome (Jul 15, 2019)

Use this (or another similar page) to find subs.  Not a fun task in general





						2SC732  Datasheet, Equivalent, Cross Reference Search. Transistor Catalog
					






					alltransistors.com


----------



## K Pedals (Jul 15, 2019)

the_grumpy_gnome said:


> Use this (or another similar page) to find subs.  Not a fun task in general
> 
> 
> 
> ...


Thanks


----------



## Grubb (Jul 13, 2021)

On this specific question, I'm troubleshooting a friend's first build which is an Uberdrive. He's subbed 2N3904s in for the transistors mentioned above. So far I've deduced that the pinout is mirrored, are they otherwise an ok substitute?


----------



## Mcknib (Jul 13, 2021)

Any general purpose NPN transistor will work, may not sound exact with differences in hFE etc but it'll work



Grubb said:


> On this specific question, I'm troubleshooting a friend's first build which is an Uberdrive. He's subbed 2N3904s in for the transistors mentioned above. So far I've deduced that the pinout is mirrored, are they otherwise an ok substitute?


As @temol pointed out in your post they are not a mirror image the base is an outer pin on the 2SC732 middle pin on the 3904 so you'd need to bend the B and C pins so the collector's in the middle and base outer if you haven't already

The 2SC732 is one of those weird pinout jobs


----------



## Grubb (Jul 13, 2021)

What has me confused is that I found conflicting data sheets when searching. Is the TM a variant? I tried a few configurations with bent pins and twisting the orientation of the transistors so as not to short the pins but haven't hit the winning formula yet. I might sub in some 2N5089s I have to see if I can get it working.


----------



## Mcknib (Jul 13, 2021)

Yep can defo get confusing

The actual silkscreen on the PCB would be left to right E,C,B if you compare it to the schematic


----------



## Feral Feline (Jul 18, 2021)

Grubb said:


> What has me confused is that I found conflicting data sheets when searching. Is the TM a variant? I tried a few configurations with bent pins and twisting the orientation of the transistors so as not to short the pins but haven't hit the winning formula yet. I might sub in some 2N5089s I have to see if I can get it working. View attachment 13624
> View attachment 13625


Have you got an example of a conflicting 2SC732 you can post?

The two depicted in the quoted post #6 are the same; and Mcnib's post #5, the diagram on the left, is the same ECB pinout as well.

To reiterate what Mcnib said: The 2N3904 is NOT a mirror of the 2SC732.

To clarify: If you look at the bottom of a transistor with the pins pointing at your eye and the flat side facing the sky, THAT is how the pinout is shown in the "TM" diagram and Mcnib's post.

If you take a 3904 with pins to your eye, flat to the sky you get L-R: E B C.
A 3904 *mirrored* to the 2SC732 (pins to eye flat to sky) L-R it'd be: B C E.
Mirrored, the two transistors would still share the same middle pin.

Take the "TM" and the "ST" versions of the 2SC732, pins to eye flat to sky... same.


Check the datasheets for your particular 2N5089 you want to try, but so far all the 2N5089 I've come across are EBC like the 2N3904. Different manufacturers may have different pinouts for the same part #, so it's good to collect different datasheets for the same part.

Hope this helps and sorry if I'm overstating the obvious. When I started out I automatically thought the view on the datasheets was from the top, expecting the view to match how you'd view the installed-component.


----------



## Grubb (Jul 18, 2021)

Thanks for the reply, we got the Uberdrive working with 2N3904s but it took me a while to get the orientation correct. On top of that it had a dead op amp. I learned a lot from fixing it and my mate will be pleased to get a working pedal back in the mail.

In the end I turned the 2N3904s backwards, placed the two pins that matched in their sockets and tack-soldered a lead from the empty socket pin around to the free-standing transistor leg. It works 😁

I interpreted that diagram as top down, hence my confusion. It makes sense now that they both say the same thing, thanks for clearing that up.


----------



## Feral Feline (Jul 18, 2021)

I found your other thread, late to the party as usual, but now understand Mcnib's reference to Temol's post in this thread was referring to the other thread. Congrats on getting it all sorted.


----------



## ANGRY_SWEDE (Sep 4, 2021)

K Pedals said:


> Does anybody know a substitute for the 2SC732s??? I’m trying to build an uberdrive...


2SC1815 works as a substitute. Appropriate ECB pinout. I used them on a fully refurbished Boss HM-2.


----------



## Mike52 (Dec 6, 2021)

ANGRY_SWEDE said:


> 2SC1815 works as a substitute. Appropriate ECB pinout. I used them on a fully refurbished Boss HM-2.


I just dropped these into an Uber Drive that calls for 2SC732s and it fired right up. Confirmed.


----------

