Module is available as a DIY project only.
This Module is currently available.
Passive ring mod
This is a very simple ring modulator circuit which will allow you to make interesting analogue sound effects using two audio sources and some kind of amplifier or recording device. Almost everyone has access to a couple of mp3 players and some powered computer speakers nowadays, so this is quite an easy way to go about it. One very familiar use for this old style of ring mod is that which produces the "Dalek" voice.
Double balanced modulators like this were traditionally used in older radio circuits using radio frequency transformers to produce suppressed carrier AM signals. If you look up circuits like that and compare it to this application, it can appear a bit confusing as the RF 'carrier' input would be connected our 'voice' input and the 'voice' input would be going into our 'tone' input.
http://www.usefulcomponents.com/main_contents/projects/simple_ring_mod/simple_ring_mod.html