Direct Pronto/Marantz RF

While designed for use with RF extenders, the RF sent by Pronto and similar remotes can also be used for direct control of many other RF devices. There is one potential complication in that the RF sent by the Pronto is double modulated. The RF carrier is modulated by the data envelope and also by a fixed 36kHz signal. The intention is to prevent non-Pronto RF from controlling the RF extender. Most RF controlled equipment will not respond fast enough to see the 36kHz so their RF receivers will output the demodulated data envelope while those that can handle the 36kHz may not respond to RF signals from the Pronto. Range is also less than optimal as the transmitted power is proportional to the duty cycle of the 36kHz carrier.

Outside North America

The Philips RU950, RU970 & RU980, the Marantz RC 5200, RC5400 & RC9200 and Onkyo CHAD send 433.92MHz RF.

433.92MHz Devices
   Ansen Electronics    ATI Remote Wonder    Clipsal Ulti RF²
   Crestron CNRFGWA RF Gateway    Elro, Intertechno    Funkschalter SET RS-202
   Gamma klik aan klik uit    Jung Radio Management    Marelco Waveman
   OTIO    Philips SBC SK 305    Viper Ceiling Fan¹
    X-10    X-10 MouseRemote
¹ Any ceiling fan using 433.92MHz should be controllable.
² Ulti uses two-way RF when learning codes. This complicates code capture.

Any device that uses 433.92MHz ±0.5MHz and Amplitude Shift Keying or On/Off Keying is a potential candidate for direct control. Devices which use Frequency Shift Keying (FSK) cannot be controlled in this way.

X-10's Powermid uses 433.92MHz in Europe. Non-RF versions of the above remotes, as well as the iPronto, can send IR to the IR2RF half of the Powermid which will repeat it as 433.92MHz RF. This method also allows control of the above listed RF devices.

Bose Lifestyle uses 27.145MHz. It cannot be controlled by direct RF from any of the listed remotes.

In North America

The Pronto TSU3000, TSU6000 & TSU7000, Marantz RC9200, RC5200 & RC5400, Onkyo CHAD, and Crestron MT-500C send 418MHz RF. While there are fewer devices that use 418MHz, the number is steadily increasing.

418MHz Devices
   ATI Remote Wonder¹    Crestron CNRFGWA-418 RF Gateway    Some Emerson ceiling fans
   LG-Zenith LSS-3200 DSS Receiver    Lutron RadioRA²    RF Thermostat
   RF Thermostat    Most IR extenders (e.g. Powermid)
¹ The ATI Remote Wonder can be tuned to 418MHz (approximately 3.5T CCW of the tuning slug)
² The Lutron RF codes appear to be too complex for the Pronto firmware to handle. Other transmitters (e.g. USB-UIRT, GC-100) may work.

Any device that uses 418MHz ±0.5MHz and Amplitude Shift Keying or On/Off Keying is a potential candidate for direct control. Devices which use Frequency Shift Keying (FSK) cannot be controlled in this way.

RF transmitters sold in the USA are required to have an FCC ID number. This can be used to determine the RF frequency at the FCC Search web site.

Other programmable remotes (e.g. some from Home Theater Master) can also send RF. If they send 418MHz or 433.92MHz and can make use of CCF hex codes, they can be used in the same manner.

The CM15A, introduced by X-10 in late 2004, combines a two-way PLC interface with a 310MHz RF receiver and a 310MHz RF transmitter. The RF components are third party daughter boards. The RF receiver is a single chip type (HiMark RX3310A). The datasheet gives the L1 and C1 values for 418MHz. Converting the CM15A to respond to 418MHz is just a matter of replacing L1 and C1 (or perhaps of just tuning L1). However, it will then no longer respond to standard X-10 RF devices like Palmpads or motion sensors.

Non-RF models of the above programmable remotes can be modified to also send RF. The RF-modified remotes do not use a preamble. It may also be possible to build a converter/repeater (IR2RF) to communicate with a specific RF device. It depends on whether there are off-the-shelf RF transmitter modules for the RF frequency used by the device.

One potential glitch is that the Pronto/Marantz RF signal has a preamble which encodes the RF extender channel, ID and IR carrier frequency. This is a short series of short pulses/spaces with a 5mS gap before the real code. The oscilloscope screenshot below shows the digital output line of an RF receiver. Three copies of the preamble can be seen emerging out of the noise before the actual code starts. In most cases it will be ignored but the 33mS + 5mS gap preamble may confuse receivers that use a similar protocol. (The Pronto & Marantz RF Extenders strip the preamble and only repeat the code itself as IR.)


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