Motorola TIP31A NPN Silicon Power Transistor TO-220
$4.99
Motorola TIP31A NPN silicon BJT power transistor in TO-220 package for vintage electronics repair, CB radio repair, ham radio bench work, audio amplifier service, power supply circuits, regulator circuits, driver stages, switching circuits, and general electronics restoration where a TIP31A-style NPN transistor is required.
This device was bench identified as an NPN silicon BJT and showed good basic transistor behavior on the tester, including hFE reading, normal base-emitter voltage readings, very low saturation voltage at the tested current, and zero measured leakage on the tester.
Historical Note:
The TIP31A is part of the classic TIP-series silicon power transistor family widely used in service-era electronics, power supplies, audio circuits, motor/control circuits, radio equipment, and general bench repair. Motorola-marked TO-220 transistors are useful restoration parts because many older boards and repair manuals were designed around these common through-hole transistor packages.
Origin Tracker
Obsolete Stock
Legacy or discontinued stock no longer in normal production flow. Future supply may be limited.
Pipeline quantities are informational and may change after arrival, inspection, sorting, testing, or donor teardown.
Compatible Radios / Boards
Useful for vintage radios, CB radios, ham radio equipment, audio amplifiers, power supply boards, regulator circuits, driver stages, switching circuits, industrial electronics, experimenter projects, and general bench repair where a TIP31A NPN silicon TO-220 transistor or suitable researched substitute is required. Buyer should confirm pinout, voltage rating, current rating, gain needs, package style, heat sinking, and circuit compatibility before installation.
RF Boneyard Bench Notes
Bench Measurements:
Device type identified by tester: NPN Silicon BJT.
Pinout / lead color reference from tester: Red-E, Green-C, Blue-B.
hFE: 66 at Ic=5.01mA.
Vbe: 0.542V at Ib=1.00mA.
Vbe: 0.611V at Ib=5.00mA.
VceSat: 0.023V at Ic=5.0mA and Ib=1.00mA.
IcLeak: 0.000mA.
Marking observed: Motorola logo, TIP31A, 026M.
Bench Evaluation:
PASS - Tester identified device as NPN silicon BJT.
PASS - hFE measured 66 at Ic=5.01mA.
PASS - Vbe readings were present and consistent with silicon transistor behavior.
PASS - IcLeak measured 0.000mA on tester.
PASS - Suitable for vintage electronics repair, CB radio repair, ham radio repair, audio repair, power supply work, and general bench restoration use.
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