SC=Special Circuit
Could be a marking only special in which case getting the pinout will allow you to try other parts. The only company that may have the records for what this part really was is ON Semiconductor. Since it is a linear part, they acquired the linear parts from Mot around 2000. They may know what the part might be. However, I doubt they will tell you.
Best bet is to try and get a schematic of the unit you trying to fix. With the inputs, outputs and power/ground identified, go from there trying similar parts with the same I/O configuration.
In the old days, when I was an App. Engr for Mot. Semi, there was no cross reference table for standard parts to SC numbers. Even back then we kept the part identification secret. Some parts were specially tested catalog parts. Some were full customs. You just never knew.
Good luck.
Could be a marking only special in which case getting the pinout will allow you to try other parts. The only company that may have the records for what this part really was is ON Semiconductor. Since it is a linear part, they acquired the linear parts from Mot around 2000. They may know what the part might be. However, I doubt they will tell you.
Best bet is to try and get a schematic of the unit you trying to fix. With the inputs, outputs and power/ground identified, go from there trying similar parts with the same I/O configuration.
In the old days, when I was an App. Engr for Mot. Semi, there was no cross reference table for standard parts to SC numbers. Even back then we kept the part identification secret. Some parts were specially tested catalog parts. Some were full customs. You just never knew.
Good luck.
Not sure what I didn't bite on. I did call On Semi - that produced no success. I know pin 14 is Vcc, and pin 7 is common. From there, all I have to do is determine +, -, and output for the other pins based on reverse engineering the pcb. PITA, but not impossible.
Schematics are not available that I have been able to find. This is a 30 year old Honeywell W936G HVAC controller. Transistors are unknown oddballs, but easy; they're all pnp, and a 2N2907A is an excellent drop in replacement. An unidentified IC is much more tricky.
Schematics are not available that I have been able to find. This is a 30 year old Honeywell W936G HVAC controller. Transistors are unknown oddballs, but easy; they're all pnp, and a 2N2907A is an excellent drop in replacement. An unidentified IC is much more tricky.
I didn;t mean to be mysterious. stoc005 suggested looking on the schematic for your unit, but you didn;t respond with what it was. That's all I meant. Now that you have specified, someone could conceivably have some old documentation. I wonder if there is a forum like this one for the HVAC crowd? There are forums for people who collect old kitchen appliances after all.
Just an off the wall hunch, contact Steve at www.blueguitar.org and tell him Enzo sent you. In his real life, he is an HVAC guy. COuld possibly be of some assitance beyond all us audio guys. At worst, you are out an email.
Just an off the wall hunch, contact Steve at www.blueguitar.org and tell him Enzo sent you. In his real life, he is an HVAC guy. COuld possibly be of some assitance beyond all us audio guys. At worst, you are out an email.
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