KR 4140 transistor pinout

[Boyum]

Kenwood guru's! Putting in new transistors. Does this interpretation of the E,C,B pinout look right? Top image is whats on the board.

 

[mbz]

Not a guru, so I would need to know what transistor TRxxx you are talking about. The board/stage that TR is on would be
helpful so as to avoid confusion...

 

[Boyum]

Thank you for your response. I am working on the main pre, tone, main board. Before I explain further I want you to know that I am a true knucklehead. Right Channel dead. Channel slowly faded away. I am just scatter shot replacing transistors and capacitors. Only working with a digital v meter.
What interest me is Q16 and Q14. The board seems to have a symbol under the trans. legs which I am trying to figure out. I know E,C,B making on the bottom of the board but I am blind in one eye and trying to make this struggle a little easier

 

[gort69]

I believe you have the the emitter and collector switched around IF Kenwood was consistent across various models. Way better to look at the schematic to see which component each lead connects to. Service manual can be found here. (scroll down)

 

[Boyum]

Thank you for your response. I am working on the main pre, tone, main board. Before I explain further I want you to know that I am a true knucklehead. Right Channel dead. Channel slowly faded away. I am just scatter shot replacing transistors and capacitors. Only working with a digital v meter.
What interest me is Q16 and Q14. The board seems to have a symbol under the trans. legs which I am trying to figure out. I know E,C,B making on the bottom of the board but I am blind in one eye and trying to make this struggle a little easier

 

[Boyum]

Thanks, do have a service manual from Hifi E. I guess I'm being a little lazy. Was hoping someone knows off the top of their head the interpation of the printed symbol on top of the board.

 

[hopjohn]

Q13, Q15 are the transistors of the corresponding channel and should help in determining pinout arrangement for Q14 and Q16 respectively. If you have the service manual it should also provide a photo of the original transistor pinout arrangement. Obviously you'll need to know the pinout of the replacements too for any of that to matter. @gort69 's advice on checking the schematic for arrangement is also an excellent suggestion.

Your top sketch is wrong. Assuming the silk-screening is correct (not all that uncommon to be wrong)
dot- collector
dash to edge of circle - emitter
dash through the circle - base

Read this:
https://audiokarma.org/forums/index.php?threads/silkscreen-symbol-question-on-kenwood.312245/

 

[Boyum]

I believe you have the the emitter and collector switched around IF Kenwood was consistent across various models. Way better to look at the schematic to see which component each lead connects to. Service manual can be found here. (scroll down)

Thanks, guess that's why I am burning up Re88'

Q13, Q15 are the transistors of the corresponding channel and should help in determining pinout arrangement for Q14 and Q16 respectively. If you have the service manual it should also provide a photo of the original transistor pinout arrangement. Obviously you'll need to know the pinout of the replacements too for any of that to matter. @gort69 's advice on checking the schematic for arrangement is also an excellent suggestion.

Your top sketch is wrong. Assuming the silk-screening is correct (not all that uncommon to be wrong)
dot- collector
dash to edge of circle - emitter
dash through the circle - base

Read this:
https://audiokarma.org/forums/index.php?threads/silkscreen-symbol-question-on-kenwood.312245/

Thank you, that is what I needed to hear. I knew this site had a guru!

 

[Boyum]

I believe you have the the emitter and collector switched around IF Kenwood was consistent across various models. Way better to look at the schematic to see which component each lead connects to. Service manual can be found here. (scroll down)

Thanks, guess that's why I am burning up Re88'

I believe you have the the emitter and collector switched around IF Kenwood was consistent across various models. Way better to look at the schematic to see which component each lead connects to. Service manual can be found here. (scroll down)

Thanks gort. Will fix

 

[Boyum]

I believe you have the the emitter and collector switched around IF Kenwood was consistent across various models. Way better to look at the schematic to see which component each lead connects to. Service manual can be found here. (scroll down)

Thanks, guess that's why I am burning up Re88'

Q13, Q15 are the transistors of the corresponding channel and should help in determining pinout arrangement for Q14 and Q16 respectively. If you have the service manual it should also provide a photo of the original transistor pinout arrangement. Obviously you'll need to know the pinout of the replacements too for any of that to matter. @gort69 's advice on checking the schematic for arrangement is also an excellent suggestion.

Your top sketch is wrong. Assuming the silk-screening is correct (not all that uncommon to be wrong)
dot- collector
dash to edge of circle - emitter
dash through the circle - base

Read this:
https://audiokarma.org/forums/index.php?threads/silkscreen-symbol-question-on-kenwood.312245/

Thank you

 

[Boyum]

Thanks for your help. Another 40 year stereo up and running!