MOTOROLA MRF857 NPN 800-960 MHz 2.1W 24V UHF RF POWER TRANSISTOR BENCH TESTED PULL
$25.00
Genuine Motorola MRF857 NPN silicon RF power transistor removed from equipment and individually bench tested prior to listing.
The MRF857 was designed for 24V UHF large-signal common-emitter Class A linear amplifier applications operating primarily across the 800-960 MHz frequency range. Motorola specified the device for approximately 2.1 watts CW RF output with a minimum power gain of 12.5 dB under the manufacturer's specified operating conditions.
This is an original vintage Motorola RF power device rather than a modern reproduction. The transistor shown is the actual component being offered.
KEY CHARACTERISTICS:
NPN silicon RF power transistor
800-960 MHz intended operating range
2.1W CW specified RF output
24V Class A RF amplifier operation
30V maximum collector-emitter voltage
55V maximum collector-base voltage
4V maximum emitter-base voltage
Approximately 17W maximum device dissipation at specified case temperature
Typical output capacitance approximately 3.3 pF
Motorola RF Line device
Four-lead RF power package
Gold-metallized RF transistor construction
Designed for industrial and commercial UHF linear amplifier service
LIFECYCLE STATUS: OBSOLETE
HISTORICAL BACKGROUND:
The MRF857 was part of Motorola's well-known RF Line of discrete silicon RF power transistors developed for commercial and industrial UHF equipment.
Motorola designed the MRF857 family during the era when discrete bipolar RF power transistors were widely used in analog communications equipment, telemetry systems, commercial radio hardware, UHF amplifier stages, and other RF systems operating around the 800-960 MHz region.
The device was designed for linear Class A operation rather than high-power switching service. Motorola documentation specified operation at 24V with approximately 300mA collector current and 2.1W CW RF output.
The MRF857 family is now discontinued and considered obsolete, making surviving genuine Motorola examples useful for restoration, legacy-equipment repair, RF experimentation, and maintaining older commercial electronics.
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
Suitable for repair or restoration of equipment originally designed around the Motorola MRF857 or electrically compatible RF power transistor circuitry.
Potential applications include:
800-960 MHz UHF amplifier stages
Commercial RF equipment
Legacy communications equipment
Telemetry equipment
Industrial RF systems
Vintage RF amplifier assemblies
Bench RF experimentation
Legacy Motorola RF circuit restoration
Replacement suitability must be confirmed against the original equipment schematic, bias conditions, operating frequency, package configuration, impedance-matching network, and RF power requirements.
RF Boneyard Bench Notes
Bench tested as an NPN silicon BJT.
Lead identification during test:
Red - Collector
Green - Emitter
Blue - Base
hFE = 65 at Ic = 5.00mA
Vbe = 0.711V at Ib = 1.00mA
Vbe = 0.799V at Ib = 5.00mA
VceSat = 0.080V at Ic = 5.0mA and Ib = 1.00mA
IcLeak = 0.000mA
Rshunt = 11000
Device demonstrated normal NPN transistor junction behavior with measurable current gain, low saturation voltage, and no measurable collector leakage during the recorded bench test.
This bench test confirms basic semiconductor functionality at the stated DC test conditions. RF output power, gain at 800-960 MHz, and full rated-power operation were not tested.
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