mình biết là có vấn đề ở chổ đó nhưng chưa tìm ra giải pháp, cảm ơn bạn nhiều. do mình dùng pin 9v nên định chia như vậy hihi. mà không biết 4,5v có chạy nổi không nhỉ, mạch datasheet thì 12 và 9v, giờ mình chuyển xuống 9v và 4,5v không biết sao. Testimonial # 8914 of 12864 (View all the 12864 testimonials) "Order was placed on a saturday evening, two hours later I could download the manuals. Very good service.

\$\begingroup\$ Not all chips have an English datasheet, particularly for cut-rate products like an RC car. However, a Google search will at least turn up pinouts and block diagram for a TC117HS. However, a Google search will at least turn up pinouts and block diagram for a TC117HS. For the TX2B-RX2B combo, have you tried using some high power drivers like 2N2222 to drive the relays, with reverse biased diodes to stop back e.m.f. Also, the TX2B provide unmodulated output at I guess pin 8, this can be fed to a decent RC circuit for increasing the range.