[Amps] 3.5 kV 2A REGULATED Power Supply: Schematic ?

R.Measures r at somis.org
Wed Dec 31 06:31:59 EST 2003



>Without a stable, low impedance bias voltage, even assuming the amplifier is
>not designed to ever draw grid current, many of today's transceivers could
>not be used as drivers.
>
>The reason is that many have spikes when first transmitting.  That spike
>will produce severe splatter in those amplifiers that assume it will never
>happen.

**  This situation is virtually guaranteed to happen if an AB1 
amplifier's G1 DC bias is adjusted using AØ-mode.   However, if the DC 
grid bias is set so that no grid current flows on the first dit of a 
string of dits, the sky is absolutely, positively, 100% guaranteed not to 
fall.  
>
>So, your "perfect" amplifier will only be able to be connected to a
>"perfect" transceiver.

**  Only if a less than perfectly competent operator is in the driver's 
seat.  
>
>But, what happens when you step on the tail of Tiger the cat, who yowls into
>the mike.  Since you have no agc (distortion), the input level will exceed
>the drive level you have set and grid current will be drawn.  At that point,
>your neighbor minding his own business 60 kHz down frequency will hear
>the problem.
>
**  I have heard contest operators whose vocal powers easily surpass 
those of domestic cats.  

>I suppose one could operate a 10 kw final at 1.5 kw so that even the
>overdrive from normal would never happen - but the few hams I know who have
>big amplifiers seem to extend themselves once in awhile (whenever they need
>to).

**  That is the difference between a competent radio operator and a 
schmuck.  
>
cheers, Colin


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