This video introduces and performs a detailed teardown of the new Rigol MHO900 series oscilloscope, focusing on the special limited-edition 1 GHz MHO918 model. The limited-edition unit is highlighted for its unique aesthetics, including a transparent rear panel, gold-plated connectors, and metal knobs. The MHO900 series sets a new benchmark for value, offering a 350 MHz, 4-channel, 12-bit oscilloscope for under $1,000, with a sample rate of 4 GSa/s and deep memory.
The teardown reveals Rigol's strategy for achieving this price point through extensive use of custom ASICs for the front-end and ADC, which have trickled down from their higher-end HDO4000 series. A key discovery is the use of a Chinese-made, Xilinx-compatible FPGA as the acquisition engine, replacing a more expensive Artix-7 chip. The video also praises the thoughtful mechanical design aimed at minimizing assembly costs, such as using a single screw type and a clever heatsink design that secures internal components without soldering. A brief troubleshooting segment occurs when the device fails to boot after reassembly, traced back to a misaligned internal connector. Finally, the video compares the MHO900's specifications and price against competitors like Siglent, UNI-T, and Owon, concluding that Rigol has created a product with an unmatched price-to-performance ratio that is likely to dominate the entry-level market.
Rigol MHO900 Oscilloscope: A Teardown and First Look
0:00:09 Introduction to the MHO900 Series: The video introduces the new Rigol MHO900 series with a special limited-edition 1 GHz MHO918 model, featuring a transparent back, gold-plated connectors, and metal knobs. Only 2,000 of these special editions will be made.
0:02:04 Unprecedented Price-to-Performance: The series starts at $999 for the 350 MHz, 4-channel model. Key specifications include 12-bit resolution, 4 GSa/s sample rate, up to 500 megapoints of memory, and optional dual 100 MHz arbitrary function generators.
0:03:26 Disruptive Market Position: The MHO900 significantly undercuts competitors. A comparable 350 MHz scope from Siglent costs over twice as much ($2,700) with only half the sample rate and 8-bit resolution.
0:08:30 Custom ASICs are the Key: The teardown reveals that Rigol's main cost advantage comes from using its own custom ASICs for the 1 GHz front-end and the 12-bit, 4 GSa/s ADC. This technology has flowed down from their more expensive HDO4000 series scopes.
0:10:35 Cost-Effective Acquisition Engine: Instead of a costly Xilinx Artix-7 FPGA, the scope uses a pin-compatible FPGA from Chinese manufacturer Fudan Microelectronics (part FM230T) as its acquisition engine, further reducing production costs.
0:13:12 Designed for Manufacturing Efficiency: The internal assembly is highly optimized to reduce cost and labor. It uses board-to-board connectors, alignment posts, a single screw type for the entire assembly, and a clever heatsink design that holds down shielding cans without needing to solder them.
0:18:25 Reassembly Failure and Fix: After the teardown, the oscilloscope fails to boot. The issue is traced to a misaligned board-to-board connector for the arbitrary waveform generator, which was shifted by one pin. This highlights the lack of an alignment post on that specific connector.
0:22:11 Slow Boot Time: Once fixed, the oscilloscope is shown to have a slow boot time, taking 1 minute and 12 seconds to become operational. It is USB-C powered and consumes up to ~57 watts.
0:35:30 Sample Rate Interleaving Explained: The 4 GSa/s sample rate is only available when a single channel is active. Using two channels drops the rate to 2 GSa/s, and using three or four channels drops it to 1 GSa/s per channel.
0:38:12 Bandwidth Test Confirms Performance: A quick test confirms the 1 GHz model meets its specification. The bandwidth is flat to 1 GHz and the -3dB point is measured to be around 1.15 GHz.