$6.55 – Waveforms: Square / Sine & Triangle, Impedance: 600 Ohm + 10%, Frequency: 1Hz – 1MHz, Voltage supply: 9-12V DC Input.
You can get Geekcreit XR2206 Signal Generator DIY Kit for $6.55 using coupon code (in Banggood). Basically copy coupon, view price history or create e-mail price alert. What is the best price?
Latest coupon code price check (UTC time):
Banggood ($6.55)
Banggood warehouse is located in China. Good or bad price? Well, this price is higher than average price ($6.22) I found coupon for you. Check this out.
Link: Banggood product page
Price without coupon: $6.89
1. ($6.55): BGCOMDIY5
just apply this code in your cart after clicking “Proceed to checkout”. Click to copy code and open shop.
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): Terence, Tabby20, 2203ActiesNL, BG1efeb0, MVC8SPRING, pROMo8cuPoN, BG00c906, BGJUNEGSG9, Cuponation9, BG589b2e
(probably won’t work, but you can try them out)
Other warehouses/versions
This item is available in 1 another warehouse/version!
1. Europe – Geekcreit XR2206 Signal Generator DIY Kit [EU] ($-3)
Aliexpress
There’re some similar (or not) items on Aliexpress
You can use link bot to get even lower price:
Click here to search by yourself. Here are coupons that you can use.
Price history and price alert
Here is price history (for all/most countries) for Geekcreit XR2206 Signal Generator DIY Kit. The lowest price was: $4.59.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).