transistor substitution

[keebler303]

If I want to replace a hard to find component with a more common one what specs do I need to consider?
I know I need voltage and current similar
rise and fall time similar (or faster?)
base voltage?
can the gain be higher than but not lower?

Thanks
Matt

[Al_The_Man]

NTE have a free cross ref to their products, down loadable program.
It all depends on what the application demands, and how the device is being used.
Al.

[keebler303]

Thanks Al
The transistors I am looking for are a special order from NTE at $12 each. They are 2N6547 from my bridgeport. I have found some replacements but they are hard to find. I was hoping for something close enough that is readily available. (digikey, local place, etc.)

Matt

[Al_The_Man]

Digi-key show them for $5.00 or cheaper for 10, next day delivery.
Al.

[pastera]

You'll be hard pressed to get a cheaper transistor with the same specs.

Mouser has them for $3.79 (2N6547) and $12.00 (NTE)
Allied and Newark are out of stock
Jameco - 500pcs min
Future - 25pcs min
Arrow - $3.12
www.electronix.com - $3.49 I don't know these guys but the take paypal and have a $10 minimum order

Aaron