[CQ-Contest] IC756PRO II RTTY Contesting Question

[Gordon LaPoint]

Lee, 
  	I don't know what was happening with your TX, I use FSK only for RTTY, but 
do use audio for psk31 and mfsk16, and other "sound-card" modes and have not 
seen the TX problem, the power always has come up to the requested level.  The 
reason for using USB-D, or LSB-D is to bypass the input audio conditioning, and 
disconnect the mic, so Compression should not be causing a problem, its turned 
off by the -D mode.  I suggest FSK mode for rtty, it allows the best RX filter 
choices, with the special TPF RTTY mode being the best for contest work.
Plus, it allows full TX with no problems with splatter or overdrive.
See Don - AA5AU's sites for info on the PRO series and RTTY suggestions.
http://www.rttycontesting.com/
http://www.aa5au.com/rtty.html
For a detailed look at the 756PRO3 and RTTY contesting see:
http://www.rttycontesting.com/icom756proiii/icom_ic756proiii_index.htm

Gordon - N1MGO

On 11 Feb 2008 at 6:56, Lee Buller wrote:

> 
> I noticed a peculiar event during the WPX RTTY Contest.  Here is what I am
> running...
> 
> N1MM Logger
> MMTTY
> SignalLink USB
> IC-756 PRO II
> 
> I am using AFSK on USB-D.  The audio is being fed in from the ACC jack
> 
> What I kept seeing is that the power output on TX would go up to about 40
> percent on the watt meter (both internal to the rig and the external watt
> meter) on the beginning of the transmission and then slow creep up to full
> power after about 2 or three seconds.
> 
> On the PRO II, it seemed the TX audio level control was clamping down on the
> audio and then letting it come up as the ALC went down.  On the ALC meter,
> there would be a spike of ALC and then it would decay to no ALC at all.  Only
> then was the power up to 100 watts.  I had compression turned off.  I think I
> am missing something here and was looking in the manual for a parameter that
> should be adjusted, but I could not find anything.
> 
> Anyone know what is going on or what I have missed?  Or, is this just the way
> it is?
> 
> Lee - K0WA