VHF transistor

D

dudyyy

New Member

• Dec 18, 2006

• #1

hello guys i want a transistor that will work in the VHF range my signal frequency is 50MHz in my country VHF transistor are hard to find will the c640 transistor work and if it is please show its datasheet casue i couldnt found it

 

Hero999

Banned

• Dec 18, 2006

• #2

That's an incomplete part number, the nearest I can think of is the BC640.

https://www.electro-tech-online.com/custompdfs/2006/12/BC640.pdf

What gain do you require? The GBWP is 100MHz so I wouldn't expect much at 50MHz, 2 maybe, if it's just an oscillator then it'll probably work but I wouldn't recommend it for an amplifier.

 

JimB

Super Moderator

Most Helpful Member

• Dec 18, 2006

• #3

Transistors identified as "c640" are probably "2sc640".
There is a tendency to miss off the 2s part of the number for some reason.

As for the question whether it will work at 50 Mhz, I guess it all depends on what you want it to do at 50Mhz?

Low noise amplifier?
Power Amplifier?
or????

JimB

 

Nigel Goodwin

Super Moderator

Most Helpful Member

• Dec 18, 2006

• #4

A 2SC640 only has an ft Min of 50MHz, so it's useless for most RF use, and certainly for your purposes!.

 

Hero999

Banned

• Dec 18, 2006

• #5

It also depends on the gain group.

See datasheet.
https://www.electro-tech-online.com/custompdfs/2006/12/319132466074.pdf

EDIT:
Nigel got there first.
The datasheet I found doesn't state the minimum ft, it just says 300MHz typical.

 

Last edited: Dec 18, 2006

Nigel Goodwin

Super Moderator

Most Helpful Member

• Dec 18, 2006

• #6

I looked in "Towers International Transistor Selector, Update 5"