[WriteLog] arrl RU test

Alan Maenchen ad6e at arrl.net
Tue Jan 10 14:00:45 EST 2017

Thanks Joe,

I agree monitoring the PC sound isn't very reliable but at least I can hear
something so I know I have the correct input device. The very weak signal
sounds like a simple broken wire somewhere. Unfortunately I'll have to wait
a couple of weeks to dig into it again due to my upcoming trip to CA.
That's a great idea about tuning in WWV for a reasonable calibration of the
setup. Most of the time when I was futzing with this, there were no RTTY
signals available.

73, Alan  AD6E

> Date: Mon, 9 Jan 2017 16:03:56 -0500
> From: "Joe Subich, W4TV" <lists at subich.com>
> To: writelog at contesting.com
> Subject: Re: [WriteLog] arrl RU test
> Message-ID: <98d79c6d-f7de-8d07-e8bd-c5e22c290607 at subich.com>
> Content-Type: text/plain; charset=utf-8; format=flowed
>  > Here is the weird part: using same rig with DX4WIN/mmtty, no
>  > problem printing; mmtty stand alone, no problem printing, Gritty no
>  > problem printing. I ran gritty window along side writelog and gritty
>  > would print close to 100%; writelog much of nothing.
> DXWin/MMTTY uses a separate copy of MMTTY.  The first thing to do is
> open the MMTTY set-up in WriteLog (Option | Setup) and make sure
> MARK is the same as the MARK frequency in the rig (Demodulator tab),
> AFC is *OFF* and Shift is *Fixed* or *FSK* (AFC/ATC/PLL tab) and
> those values are saved as the "HAM Defaults".  You can compare the
> settings in WriteLog and DX4Win/MMTTY if needed.
> > If I set the mixer control to monitor the sound card input by
> > outputting it to the PC earphones, the K3 audio is there but very
> > weak.
> Monitoring through Windows is not very reliable.
> Tune a steady signal (e.g. the carrier from WWV) and set it to the
> RTTY Mark Frequency.  Set the RX Main or RX control on the microHAM
> interface to 12:00.  Open the Windows Sound Control Panel and double
> click on "Line (microHAM CODEC)" (for MK II, DK II) or "mic (USB Audio
> CODEC)" (for USB Interface III or DigiKeyer) and select the LEVELS tab.
> Adjust the slider and the RX Gain pot until you see the first green
> bar.  With an S9 signal on my K3, that happens with RX Gain at 12:00,
> the Windows input slider at 80% and the K3 Line Out at 10.
> A more sensitive way to adjust audio input is to use audio spectrum
> analyzer software (e.g. Spectran).  Set the Windows input gain to 60%
> and adjust the RX Gain pot on the microHAM interface so the background
> noise level raises 30 to 40 dB above the no input nose floor of the
> sound card.  With my K3 that occurs with RX Gain at 9:00, Windows input
> gain at 60% and the K3 Line Out at 10.  By setting the no signal noise
> 30 to 40 dB about the sound card noise floor, signals remain well above
> the noise floor even when the transceiver's AGC is activated and strong
> signals do not clip/saturate either the transceiver or the sound card.
> 73,
>     ... Joe, W4TV

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