The Acer Aspire One netbook is known to work well for mobile monitoring with external USB sound cards, of 3 radios.
Most folks start thinking about doing some decoding on their own after familiarizing themselves with the application by connecting to internet ATCS servers. Now that you're ready to take that step, here's how to get going.
You've already got a radio with a discriminator tap, so you need to plug that line into a sound card for decoding. Use the Line-In jack (not the Microphone-In) on the sound card.
Within ATCS Monitor, go to Configure->Options->Data Source and select Sound Card. If you have more than one sound card, select the appropriate one and OK your changes. Press the Start Monitoring toolbar button and you may start to see data decoding. To adjust for best decodes, use the Analyze Signal toolbar button to adjust your volume right from the application. The waveform at the top should occupy roughly half the total height and peaks should not get clipped off. A middle setting on the recording volume slider is usually adequate for most radios.
If you are using a laptop and are using the Mic-In instead of a Line-In, you should strongly consider spending the $25 for an iMic (see below), you can probably get some decodes from the built-in Mic port, but be prepared for poor performance. In windows, you'll want to disable the Mic Boost option through the sound recording controls. The easiest way I know to access this is by going to Start->Run, then sndvol32 /r. Click the Advanced button if there is one, then uncheck the Mic Boost option and close out. When adjusting recording volume, start with a very low setting.
Before stating anything else, this is the most important thing. The Griffin iMic or iMic2 is the most cost-effective sound "card" you can get. It's an outboard USB device that funtions like an internal sound card.
- Inexpensive - ranges from $22 to $40 each
- Proven - with ATCS Monitor, it just works, period
- Performs - there has not been a report of a sound card that provides more reliable decodes, but plenty that perform much worse
- Versatile - Connect it to whatever computer you happen to be at. If you need to listen to multiple radios simultaneously then connect two, no problem...
Attention laptop users: The iMic is a must-have. Most laptops only have Mic inputs, not line inputs. Mic inputs have too much gain, due to too much amplification, so they don't decode well. Fortunately, all modern laptops have USB ports.
iMic can be purchased directly from Griffin Technology or often cheaper at common online outlets such as amazon.com or buy.com. At least get one to use as a benchmark when testing other sound cards. Nope, I don't own stock, but I'm thinking about it!