[Kenwood] 3SK22 FETS used on R-599A be replaced with 40673?

[Peter A Markavage]

I think we covered this back a month or two ago. The 40673 and the 3N200
can also be used in place of a 3SK22. I believe the lead configuration is
the same but it would be wise to check before you put it into the
circuit. If the 1N60's are still good, leave them in. Note, if one or
both of these diodes is shorted, you will have very low sensitivity. Also
check Q3, 2SK19. A bad or weakening Q3 will also result in low
sensitivity.

Pete, wa2cwa

On Mon, 1 Sep 2003 22:35:42 EDT Cqk1jeb@aol.com writes:
> Can one replace the 3SK22 FET with a 40673 FET? I have a few 40673 
> FETs. I do 
> not have any NTE222s.
> The front end of my R599A receiver has low gain. I think the RF amp 
> needs to 
> be replaced.
> 
> Also how do you test a dual gate MOS FET? A transistor is very easy 
> to test.
> 
> Since the 40673 are diode protected FETs do I still need the dual 
> 1N60 diodes 
> ahead of the RF amp?
> 
> I got the new function switch connected successfully! My T599A works 
> great!
> (The previous owner had removed the switch without keeping track of 
> the 
> wires.)
> Now, I just need to get the R599A working....
> 
> JohnB
> K1JEB