Dual Gate Mosfets (more)

Gerald Wolczanski jerrywlinux at comcast.net
Mon Nov 5 06:24:45 CST 2012

See (from the QRP-l forum GD3YEO):
I have been reading all the responses to my request for a 40673 and am 
overwhelmed. I had determined from all the responses including yours 
that the BF998 was what I wanted. I then looked at SMT to conventional 
leaded part solutions and came up with an adapter board of sorts from 
Capital Advanced Technologies which is handled by Digikey. This little 
adapter board adapts the SOT143 package to a SIP package and they only 
cost less than $1.50 ea in single quanity. The BF998 are 14 cents each 

Another ham just suggests flipping the BF998 upside down and bending the

Most posters suggests the BF998 is actually BETTER than the 40673.
W7ZOi suggests that when the MOSFET mixer is implemented properly, it
can offer very good performance.  It would certainly run rings around
the NE602 family of devices, which ought to be outlawed IMHO.


On Sun, 2012-11-04 at 20:35 -0700, Joseph Bento wrote:
> When did dual gate mosfets such as the 40673 or 3N211 enter the 
> unobtanium category?  I managed to find a source tonight for a few at 
> reasonable prices - $3.00ea, but these are parts that used to sell for 
> pennies.  Now it seems they are going the way of tunnel diodes, 
> germanium transistors, and other semiconductors of old.
> I always found a dual gate mosfet to be a simple way to cobble together 
> a quick mixer.  Guess I'm going to have to learn new methods.
> Joe, N6DGY
> _______________________________________________
> Tacos mailing list
> Tacos at amrad.org
> https://amrad.org/mailman/listinfo/tacos

More information about the Tacos mailing list