Polarity of 2SC1970 and 2SC1971
 

Hi All,

Two RF transistors, 2SC1970 and 2SC1971 are supposed to have BEC
pinouts according to data sheets. However, it seems that such
transistors with BCE pinout also exist; resistors in one circuit caught
on-fire when I plugged a 2SC1971 into a BEC socket (based on data
sheets, I assumed the transistor had BEC pinout). After replacing the
resistors and bending the leads of the transistor, the circuit worked
properly. Yes, the socket was wired correctly for BEC pinout. Has
anyone ever come across the BCE pinout versions of 2SC1970 and/or
2SC1971?

C.W.

Two RF transistors, 2SC1970 and 2SC1971 are supposed to have BEC
pinouts according to data sheets. However, it seems that such
transistors with BCE pinout also exist; resistors in one circuit caught
on-fire when I plugged a 2SC1971 into a BEC socket (based on data
sheets, I assumed the transistor had BEC pinout). After replacing the
resistors and bending the leads of the transistor, the circuit worked
properly. Yes, the socket was wired correctly for BEC pinout. Has
anyone ever come across the BCE pinout versions of 2SC1970 and/or
2SC1971?
==================================
According to Tower's International Transistor Selector , both 2SC1970 (Ic
max=0.5A) and 2SC1971 (Ic max =1A) are NPN RF power transistors in a TO220
package
Pinout 2SC1970 is BCE
Pinout 2SC1971 is BEC

The above pinouts are confirmed by the (PDF format) datasheets which I found
by doing a Google.

Frank GM0CSZ / KN6WH

Scary!

I have noticed some with tabs isolated and some not. Gotta check the
spec sheets. NTE replacements worked fine in TS2000 and are probably
re-marked OEMs.

Analog VOM would help.

"Highland Ham" wrote in message
...
Two RF transistors, 2SC1970 and 2SC1971 are supposed to have BEC
pinouts according to data sheets. However, it seems that such
transistors with BCE pinout also exist; resistors in one circuit
caught
on-fire when I plugged a 2SC1971 into a BEC socket (based on data
sheets, I assumed the transistor had BEC pinout). After
replacing the
resistors and bending the leads of the transistor, the circuit
worked
properly. Yes, the socket was wired correctly for BEC pinout.
Has
anyone ever come across the BCE pinout versions of 2SC1970 and/or
2SC1971?
==================================
According to Tower's International Transistor Selector , both
2SC1970 (Ic
max=0.5A) and 2SC1971 (Ic max =1A) are NPN RF power transistors in
a TO220
package
Pinout 2SC1970 is BCE
Pinout 2SC1971 is BEC

The above pinouts are confirmed by the (PDF format) datasheets
which I found
by doing a Google.

Frank GM0CSZ / KN6WH