[Amps] LDMOS availability

[Ron Youvan]

   On 06/10/2017 01:48 AM, Jim Thomson wrote:

  /* snip */
> ##  I looked into the  two-tiered bias scheme back in the 70s. When it 1st came out
> in QST, its function was to cut off idle current  between dots and dashes  for qsk cw.
  /* snip */

   I did this in 1973, I had to because of the electron noise from the
two 6146s in my Heath DX-100, as I started as a novice with an FET "TR"
switch.  All I did was turn the "clamp" tube adjustment until all 
current quit flowing.  Worked great!

BTW:  The "TR" switch was fed by a one turn shielded loop of tiny coax
(Teflon coated) around the cold end of the low frequency tank coil.
The result was the receiver could only hear the frequency that the PA
tank was tuned to.
   (lightning and that blasted "woodpecker" marched right through)

   My first contact was QSK, I find it annoying now because of all of the
noise on the bands, including local noise. (I turn the volume down when
I transmit now.)
-- 
   Ron  KA4INM - Youvan's corollary:
                 Every action results in unwanted side effects.