Students must always practice with the Sruthi. Here are some options to purchase a good digital tambura from Amazon, India. You can also find them in musical instruments stores in the major cities of South India (Chennai, Bangalore, Hyderabad).
You can purchase the following power cable for the Sruthi box
https://www.amazon.com/gp/product/B0025ZPX6O/ref=ppx_yo_dt_b_asin_title_o09_s00?ie=UTF8&psc=1
For iOS devices please download one of the following apps
iSruthi - Tampura Sruthi Box by Mindlab Systems
https://apps.apple.com/ca/app/isruthi-tampura-sruthi-box/id669394303
iTanpura by Prasad Upasani
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