RoMac Basic Equalizer FAQ
Download and install the program. After installation and the software starts up without an error, normally that means your system is compatible. After proper sound card setup, if you hear yourself through the speakers with a slight delay, your system is definitely compatible.
If you hear a trailing echo while listening to
yourself through your computer speakers or through the monitor on your
radio, you are probably hearing audio from the speaker going
back into the microphone. Many times an operator will then turn up the
volume on the speaker to listen to the echo closer, and will exacerbate the problem. When the software
is hooked up to your radio, this will not be an issue.
Without the license key the software operates for a cumulative running time of 20 hours.
First determine if the distortion is from
overdriving something, or is it RF getting into the audio system.
The peak indicator of the equalizer should be peaking up about 1/3 to 1/2 the way up. None of the indicators should ever be yellow or red. See the help file for the equalizer to understand setting up the audio levels in your system.
The use of an isolation transformer is a necessity when using the software for transmitting. The reason you need an isolation transformer is to ensure the sleeve connection from the sound card output is not grounded. Click here for sample interface circuits.
One might think the sleeve is ground, it isn't. It's common to the two stereo channels. If you try connecting the sound card to the transceiver without an isolation transformer, the sleeve will be grounded at the radio.
If everything looks good as far as the audio levels go, then it could be RF getting into the system. If you have built your own interface, enclose it in a metal box, not plastic. Make sure that neither side of the input (from sound card line out) to the isolation transformer is grounded.
Use quality shielded cable and shielded type connecters. Make sure all connections are tight and soldered well.
Make sure the computer case is well grounded to the stations ground. Do not use a small gauge wire, use a piece of coax braid, preferably 1/2" wide. Make it as short as practicable.
You may also try using some ferrite cores at the line out, line in on, and Mic in on the computer and/or on the interface unit. Wrap 8 to 10 turns using type 43 material.
For really stubborn cases of RF on the audio, you may
want to remove the sound card and bypass the tip and sleeve of the Mic In,
Line In, and Line Out with .01 uF capacitors. Even though today's sound
cards built using surface mount components, the area around the audio
jacks still should have some room to work. You will need to an
ohm meter to find which connections are the ground, sleeve and tip.
Read this excellent article on RFI problems and how to solve them (pdf format)
The RoMac Basic Equalizer has a very small delay in it. The delay is from the processing of the audio stream. The slower your computer the longer the delay will be.
Go to "Setup->Select Sound Card" and set the buffers to "Small" and the sample rate to 22050. This will help reduce the delay.
If you are keying your transmitter with a manual PTT arrangement, make sure to leave your PTT switch down just a bit longer than normal. If you are using the audio stream from the equalizer to drive the VOX in your transmitter, this will not be an issue.
Make sure you didn't start a second copy of the equalizer. If it is the only instance that is running, it is probably due to lack of system resources or a sound card incompatibility. It may also be your preferred playback and recording devices in the Windows Control Panel are set to something other than your sound card.
Ensure your sound card drivers are up to date and DirectX compatible. Install DirectX 8.0 or higher.
The smallest system that the equalizer has been tested on is a 400 MHz Celeron with 128 Mb. You will need to upgrade your memory capacity and/or processor.
||Check the preferred sound devices in the Windows Control Panel. They should be set to your sound card, not something else such as a modem device or mapping device.|
||Make sure you're not mixing zero's and the letter O. The "0" is a bit more elongated compared to the letter "O"|
||Most sound cards
have a positive DC voltage on the "ring" of the microphone connector, in
order to work with the typical electret computer microphone. Although
your microphone is monaural, use a stereo jack to connect the
microphone, and leave the ring floating (not connected).
If wiring a balanced microphone, + to tip, - and shield to sleeve.
||Check to see if the
software is set to run in a compatibility mode. Go to Windows help and
type in "make older program work" and select item #1. Make sure the
shortcut is set not to run in any compatibility mode for an earlier
version of windows.
Also ensure that any sound card drivers installed are 100% Vista or Windows 7 compatible.
||We are aware of the
problem and not sure if its our software, or Vista or the driver from
M-Audio. Usually if you go to the Select Sound Card dialog and click
"Okay" to reinitialize the sound card, the audio will be clean.
This does not appear to be an issue under Windows XP.
When we have more information, it will either be fixed, or the information will be posted here.