Need help finding a replacement transistor?

[Seth Nitz]

I have an old remote controlled boat that used to be my grandfathers back in the 80s that I am trying to restore. Everything works great except that the boat will not go in reverse. I opened up the speed controller and found what I believe to be a blown transistor or voltage regulator. Sadly I do not have much knowledge on this subject and need some help. The part in question is towards the bottom of the picture attached. I think it says B828 (maybe B826?) R0E4. Any help would be greatly appreciated!

 

[Minder]

There is a 2SB828 that may be the equivalent?
http://rtellason.com/transdata/2sb828.pdf
M.

 

[HellasTechn]

I could check my old parts if you can wait a couple of days.

i may actually have a 2sb828 or you can just order from ebay

 

[hevans1944]

And if that IS a 2SB826, the 2SD1062 next to it is the other half of an PNP/NPN complementary pair. Google 2SD1062 for a datasheet describing both parts.

 

[Seth Nitz]

Minder, I do believe that it is some sort of a switch since the part right next to it looks fine and the foward function works. Does it matter that the 2sb828 is rated for 50v when the battery pack is only a 7.5v?

Hellastechn, yeah no problem. There is no rush!

 

[HellasTechn]

Yes i think it says B826

 

[Seth Nitz]

Hevans, that would make since. I believe the two parts control the foward and reverse function.

 

[hevans1944]

Minder, I do believe that it is some sort of a switch since the part right next to it looks fine and the foward function works. Does it matter that the 2sb828 is rated for 50v when the battery pack is only a 7.5v?

Hellastechn, yeah no problem. There is no rush!

As long as the transistor is rated for a higher voltage than what you are applying to it (7.5 V in this case), you are good to go.

 

[HellasTechn]

As long as the transistor is rated for a higher voltage than what you are applying to it (7.5 V in this case), you are good to go.

Unless you go too low to bias. right ?

 

[Seth Nitz]

Will any PNP transistor work? Does it have to be a 2SB826 transistor?

 

[dorke]

The part to the right of that 2SB826 looks like a relay.
In this case you should check the diode seen behind the 2SB826.
Driving relays and motors (inductive loads) makes life "miserable" for transistors and they need help/protection.

In general you can replace a part with a different one with equivalent or "better" parameters.
If you can get the same part it is the way to go.