Preamp with remote using radio not ir

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I have a "B" pair of speakers in another room and would love to control the volume from there. My previous cable box was controlled by radio so I could mute and change music stations in either room--it was great!

So, know of any kits that use radio freq instead of ir?

Hoping to find something I can put my own motorized alps 10k into ...

Cheers,
Jeff
 
Practically speaking, there is little difference between transmitting over RF or IR. The control signal is a pulse train, and as long as you can get that signal to the other end, it doesn't matter how it gets there.

The actual RF modules to send and receive the signals are dirt cheap these days, try eBay, searching for "arduino (RF,radio)" (no quotes). The only reason to include arduino in the search is due to its popularity; these things are marketed to arduino users. You should find transmitter/receivers for $2 a pair, including shipping.

Those modules are easy to use, you put digital signal (pulses) in to the transmitter, and get the same(ish) digital signal out of the receiver, if all goes well. For IR, the signal is a series of pulses modulated at around 40 kHz, but you want an unmodulated signal. If you want to retrofit an existing IR remote to use RF transmission, you will need to find an un-modulated signal or demodulate that signal first, not a difficult task. On the receiving end, almost all IR receivers output an active low, demodulated signal, with an open collector output, so if the RF module also has an OC output, you can wire it output directly to the IR module's output (wired-OR). If the RF module is active high, then use it to drive a NPN transistor to create a open-collector active low.

The biggest caveat in adding RF to an IR product is noise. The RF modules tend to increase their sensitivity enough to demodulate RF noise, in the absense of your actual transmitted RF signal. As long as the receiving microcontroller firmware is robust enough to reject a fairly constant stream of garbage, then it should work. IR receivers tend to reject noise better, and don't output much of anything until a signal is received.

For AndrewT: You can probably add RF to an IR remote, but you need to find the frequency that the original device uses. Usually it will be one of: 315, 418, or 434 MHz. Usually the standby current of the transmitters is very low so you can leave it powered 'on' all the time (of course it only transmits when a signal is applied).
 
I have a "B" pair of speakers in another room and would love to control the volume from there. My previous cable box was controlled by radio so I could mute and change music stations in either room--it was great!

So, know of any kits that use radio freq instead of ir?

Hoping to find something I can put my own motorized alps 10k into ...

Cheers,
Jeff

I posted about my quick-n-dirty solution using one of the
ebay RF remote kits. You could go with one of the motorized
volume control kits, like this one.

Remote the power on and Remote control the volume board sz-2 | eBay

http://www.diyaudio.com/forums/anal...rf-controled-pga2320-minivol-ch-selector.html
 
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This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.