2N3866 Transistor Data

Key transistor data for the 2N3866 RF power transistor including key electrical parameters, pinout, package type and many other key transistor datasheet details.

This is an NPN silicon high frequency transistor designed for amplifier and oscillator applications in a variety of forms of equipment.

It is suitable for output or pre-driver circuits in VHF and UHF equipment.

It has been also used by many radio amateurs in HF, VHF and even UHF transmitters, often as the output device for VHF and UHF.

Key details and performance parameters for the 2N3866 transistor.

Transistor parameters & data
Parameters	Details
Transistor type	NPN silicon RF power transistor
Package type	TO39
V_CBO max (V)	55
V_CEO max (V)	30
V_EBOmax (V)	3.5
I_C max (mA)	400
T_J Max °C
P_TOT W	5 dissipation max
f_T min (MHz)	500
C_OB	3pF
h_fe	10 - 200
I_C for h_fe
Similar / equivalents	Comparable to 2N3553

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 parameers 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

There are few interesting pints and precautions to be noted for te 2N3866.

• Heatsink

A heatsink is often used with this transistor to enable it to provide its full output capability. This is normally in the form of a slip on extra onto the can, but remember the can is connected to the collector so care may be needed to ensure this does not physically touch other parts of the circuit and become shorted to ground,etc. Stray capacitance should also be remembered as well.

• Versatility

The 2N3866 has found applications in a wide range of electronic equipment, including:

Commercial Communication Equipment: Employed in various commercial communication systems, including land mobile radios and point-to-point communication links.
Industrial Equipment: Used in industrial electronics applications such as RF heating and industrial control systems.
Test Equipment: Utilised in various test and measurement equipment, including signal generators and spectrum analyzers.
Amateur Radio Transmitters: Used as output transistors in VHF and UHF amateur radio transmitters.

• Availability

While the 2N3866 may not be as widely manufactured today as it once was, it remains a significant component in the history of RF electronics.

Many modern RF power transistors have evolved from earlier designs like the 2N3866, incorporating improvements in performance and reliability.

While the 2N3866 was originally manufactured by RCA, and it was also widely manufactured by Motorola, and other manufacturers may have produced compatible devices with similar specifications.