What the thread found

• The SPX-68S and SPX-68G transmitters showed equivalent signal strength and reception performance compared to a Modulus 3000 when tested side-by-side with professional diversity receivers and budget monitors across distance and obstacles.
• The SPX-68S costs under $700 USD with a $50 cable, making it significantly more affordable than competing options like the Modulus 3000.
• The SPX-68S provides nine channels in the 61-69 frequency range while the SPX-68G provides five channels that can be tuned via an internal potentiometer and covers both NTSC and PAL standards.
• RF-Links also manufactures the GX-68 and GX-68/H models offering 50 UHF channels at approximately the same price as a Modulus transmitter.
• High-channel Modulus transmitters can cause interference with focus assist devices when placed close to them because they transmit unintended signals on frequencies beyond their selected channel, while cleaner RF designs transmit only on the selected frequency.
• An RF-Links transmitter positioned away from a focus assist device and tested across various distances showed no observable interference problems in trial use.
• All wireless video transmitters produce some degree of spurious harmonic emissions, with signal cleanliness varying significantly based on circuit design and component selection.

Depends on

• The performance comparison was conducted outdoors at a tennis stadium and was described as non-scientific.
• Long-term durability and shielding performance of the RF-Links units remain untested in the discussion.
• The interference testing with focus assist devices was limited to anecdotal reports and informal trials rather than controlled measurements.
• Claims about signal cleanliness are opinions rather than measurements with test equipment.

Gear in this thread

Moduluscatalog, BFD

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