Home » Component data » Transistor data » this page

MRF8004 Transistor Data

Key transistor data for the MRF8004 RF power transistor including key electrical parameters, pinout, package type and many other key transistor datasheet details.

The MRF8004 is described as being designed use in large signal output amplifier stages.

It is intended for use in Citizens Band communications equipment operating at frequencies up to 30 MHz.

Its high breakdown voltages allow a high percentage of 'Up-Modulation' in Am transmitters.

Key details and performance parameters for the 2N4427 transistor.

Transistor Datasheet Parameters & Data
Parameters	Details
Transistor type	NPN silicon RF power transistor
Package type	TO39
V_CBO max (V)	60
V_CEO max (V)	30
V_EBOmax (V)	3.0
I_C max (A)	1 continuous
T_J Max °C	200
P_TOT W	5
f_T min (MHz)
C_OB	35pF typical 70pF max
h_FE	10 min
I_C for h_fe	250 mA
Similar / equivalents

Outline:

Pinout:

Explanation of transistor parameters

Parameter	Explanation
V_CBO Max	Maximum collector-base voltage with emitter open circuit .
V_CEO Max	Maximum collector-emitter voltage with base open circuit.
V_EBO Max	Maximum emitter-base voltage with collector open circuit.
V_CEsat (included where applicable)	The voltage drop across the collector-emitter when the transistor is fully saturated (acting as a closed switch).
I_C Max	Maximum collector current.

Parameter	Explanation
T_J	Maximum junction temperature.
P_TOT Max	Maximum device dissipation normally in free air at 25°C unless other conditions indicated.
f_T Min	Minimum cutoff frequency at which the current gain in a common emitter circuit falls to unity.
C_OB Max	Maximum collector capacitane, normally measured with emitter open circuit.
h_FE	DC current gain for H_FE at I_C. [Note hfe is the small signal gain and although this may be slightly different, the transistor current gain will vary considerably from ne transistor to the next of the same type.]
P_TOT Max	Maximum device dissipation normally in free air at 25°C unless other conditions indicated.

These are the main transistor parameters that have been included in our list. There are others, but these help quantify the main elements of the performance of the transistor.

Read more about . . . . Transistor Data-sheet Specifications & Parameters.

Please note, that the data given is the best estimate we can give within a tabulated summary of this nature. Parameters also vary between manufacturers. Electronics Notes cannot accept any responsibility for errors, inaccuracies, etc, although we do endevaour to ensure the data is as accurate as possible.

Notes and supplementary information

• Availability & sources

The device is available from a very limited number of stockists and electronic component distributors. Old stock may be required to obtain these, or a more modern equivalent could be used.

• Additional details

The MRF237 was used in many HF communications radios and in particular Citizens; Band radios where it was a low cost and easily available part.

The transistor was specified as being able to provide 3.5W power output with a power gain of 10dB and a typical efficiency of 70% at 27 MHz when using a 12.5 VDC supply.

it is worth noting that the emitter connection is on the wire closest to the tab on the package in line with normal convention - a few Motorola RF power transistors do not follow this standard.

• RF amplifier circuit

A basic RF amplifier circuit that could be used for the MRF8004 is given below.

The circuit was intended as a test circuit for the MRF8004 but can be used as the basis of an RF power output or driver circuit.

The values for 27 MHz test circuit can be:
C1, C2 9.0 - 180pF VHF types
C3, C4 5.0 - 80pF VHF types
C5 0.02µF disc ceramic
C6, 0.1µF disc ceramic
L1 = 0.22µH moulded choke
L2 = 0.68µH moulded choke
RFC1 = 4 turns #30 enamelled wire wound on Ferrocube bead types 56-990-65/3B
RFC2 = 26 turns #22 enamelled wire wound as two layers 13 turns each with 1/4 inch inner diameter