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Second pass after reading the MAX2871 datasheet in full and re-checking the market premise. - New 1.1: Foxeer and iFlight wideband VTX are not evidence of a new chip. OpenVTx already drives the RTC6705 from 5000 to 5999 MHz, so 4.9 to 6.0 GHz is 50 MHz beyond what it already claims. Divimath stays the only vendor claiming otherwise, and no teardown was found for any of them. - New 4.4: domestic Chinese synthesisers, off LCSC. X214 (SWIC) is the lead, same package class and same VCO-plus-multiplier topology as the RTC6705. Datasheet is behind a member login and the vendor is a CETC subsidiary. - Section 8 replaced with an actual design: 26 MHz TCXO, PFD 1 MHz, integer-N with N = freq_MHz, third-order loop filter at 505 Hz and 45.8 degrees, 39 pF capacitive injection into TUNE for +-3.8 MHz, gain and PA budget, supply pushing budget, firmware contract, prototype scope, cost. - 8.4: VAS cannot be used at this loop bandwidth. Its state machine clock is fixed at 50 kHz against a 320 us loop time constant, so band select must be manual via the on-chip Tune ADC. - Corrected: the loop does not need to be under 100 Hz, because the receiver clamps per line rather than per field; and a 12 dB gain block cannot reach 25 mW since APWR only trims downward. - Section 10 shrank to what is genuinely still unverified.