Welcome to AudioKarma!
The G-5700,6700&7700 are very similar, all using the same F-2980 main board. The higher numbers have more WPC and improved tuners.
The first thing I would do is to ensure that it powers up and the Safely Operate LED goes green after 5-10 seconds.
Then select FM with the Mode switch and verify that the digital display operates correctly.
Turn the tuning knob and see if the dial pointer and the digital display agree.
Dial through enough frequencies to check the operation of every segment (7) of each digit displays correctly.
Does the tuning indicator change as you dial through/past stations?
(You may have to touch the external FM antenna terminal to get a signal.)
If you have some small 8Ω speakers or headphones with a ¼" plug, you can listen to the output if you have an FM station.
An adapter cable with a 1/8" jack and L/R RCA connectors will let you play your phone or .MP3 player through the AUX input.
Assuming that you decide to buy the G-5700, You should strongly consider these suggestions before settling in to enjoy your Sansui:
Register (free) at
www.HiFiEngine.com and download the SM that covers all three of these receivers.
Replace the four 100Ω trimmer pots (VR01-04) on the F-2980 bd. Search for more info on this.
Following procedures you can find here on AK, adjust the pots at their initial position before applying power.
Adjust the DC Offset, then the Bias. It may be helpful to read some of the 200+ pages in EchoWars stickey:
http://www.audiokarma.org/forums/index.php?threads/amplifier-distortion-dc-offset-and-you.5634/
I would let it play at low levels for a couple of hours before trying to share it with your neighbors.
Enjoy - - -