Hi, I have good experience with the Fly Sky FS-TH9X, 9 channels, which is a low priced radio. It's supplied with the XL4200 excavator as standard. A small drawback is that servo movement can not be put higher than 120%, but that's no real issue in most cases. It seams surprisingly good compared to its price at around 100USD. A bit tricky menus and not 100% clear instruction manual compared to more expensive radios/brands, but with some search on the net one will find an answerer to most issues.. I've also got the Airtronics / Sanwa SD-10G which is 3-4 times more expensive, midrange. 10 channels. It got 150% servo travel as max. It's got a bit better menu and instructions book, but it's less value for money compared to the Flysky. I used it for my truck. Just bought another Flysky to use for my excavator. It's possible to use one radio for several models, but I just bought a separate radio for the excavator, since it was that low priced, and seams to work OK. (For a 10K airplane I would possible go for a more expencive radio than the Flysky, but for construction equipment not too much can go wrong it radio should break down during operation..
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