[TowerTalk] Short-Snort

Joe Subich, W8IK w8ik@ibm.net
Sun, 18 Oct 1998 16:45:40 -0400



> 
> Not being a frequent amplifier user, I can't say I've experienced
> this problem.  But I _am_ a bit bewildered to hear that the amp
> and transciever makers have apparently not been in communication
> with one another.  And I must wonder why on earth anyone would
> design an ALC circuit that had less than 10 times the bandwidth
> required to follow the risetime of the envelope of the expected
> input signal.
> 

The problem isn't amplifier designers, it's the radio designers. 
Check almost any "modern" solid state rig and you will find an 
initial overshoot on the first CW character ... even without an 
amplifier connection.   The transceiver circuits have almost no 
"standby" ALC bias so at the first CW "dit" the transmit circuits 
are running wide open.  The ALC attack time seems to be deliberately 
"slow" ... probably to avoid acting like RF clipping for SSB.  



--
FAQ on WWW:               http://www.contesting.com/towertalkfaq.html
Submissions:              towertalk@contesting.com
Administrative requests:  towertalk-REQUEST@contesting.com
Problems:                 owner-towertalk@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm