Connect the 78 RPM turntable to your RCA-enabled receiver if it is not already set up. Run a single ground wire around the turntable and receiver's ground connectors to reduce noise and feedback. Screw the ground connectors down so that they secure the ground. Insert one set of the RCA cable plugs into the 78 RPM turntable's color-coded RCA output ports. Insert the other set of plugs into the receiver's color-coded RCA "Phono" or available "Line In" ports.
Connect the receiver to your personal computer. Insert the RCA-to-TRS cable's RCA plugs into the receiver's "Phono Out," "Tape Out" or available "Line Out" ports. Insert the TRS end of the cable into your computer's "Line In" port. You may affix an RCA-to-TRS adapter to one end of an RCA cable if you do not have an RCA-to-TRS cable.
Set the turntable's needle to the point on the 78 RPM record from which you want to record.
Run your audio recorder software. Use Audacity if you do not have an audio recorder utility (see Resources). Push the audio recorder software's "Record" button. Push the "Play" or "Start" button on the 78 RPM turntable right away to minimize delay.
Push the "Stop" button on your audio recorder software when the desired music stops playing. Push the "Stop" button on the turntable at this point as well.
Save the digital recording as a new audio file. Click "Save As" from your audio recording software's "File" tab. Give the file a name and file format that is compatible with your CD writer program, such as MP3 or WAV. Click the "Save" button to render the recording. Repeat Steps 3 through 6 for the other side of your LP record if necessary.
Open the rendered recordings in your CD writer program. Create a new playlist or burn list that includes the rendered recordings.
Insert a blank writable CD into your computer's CD writer drive. Click "Burn CD" to complete the 78 RPM record's transfer to CD.