I am setting up my home theater with an Onkyo Receiver and an MX-850 remote. I noticed there is an IR in port on the back of the receiver. I assume it is 3.5mm. Can I construct a cable with 2.5mm on one end and 3.5 on the other and control the receiver directly with no flasher on the front?

Yes and No.

By itself, the MRF-250 will not work with the IR in on an Onkyo. If you want to control the Onkyo in this way, you will need to buy a xantech amplified connecting block, and put it between the MRF-250 and the Onkyo.

fish,

Why so?

The Xantech connecting block can mix emitters with the IR cable to IR in; why not the MRF-250? Just a buffered output either way, I'd assume.

I guess you have tried?

Yes, I'm an Integra dealer, and ran into this problem some time ago.

I talked to URC about it, and it has something to do with the MRF having a "common Ground", or "Floating Ground", or something like that. Bottom line, it won't work.

So what I do is come out of the MRF with an emitter cable with the emitter cut off (you will need to figure out which wire is signal, I think it's the gold one), and go into an AMPLIFIED Xantech connecting block . It has to be amplified because at this point you are dealing with emitter voltage,then into the serial IR.

This is really shortsided thinking on URC's part for us custom guys. IMHO, they need to get with the rest of the industry and put 3.5mm jacks on the MRF, allow it to work with serial IR, and have a High IR out jack for connecting block expansion.

Just my 2c.

So by the time you go thru all that, it's better to stick another emitter on the Integra.

Now that you mention it, I did have to run an emitter recently when the IR in didn't work with an MX remote.

The new MRF-300 has 3.5 mm jacks. The problem was that their engineers were from oversees, where I guess the standard was 2.5mm for some reason. The engineers fought the sales team for a while about it, but apparently sales won out (and rightly so with all of our complaining). MRF-300 is shipping at the end of this month, I believe. We're looking forward to testing it - the antenna is detatchable, so if there is interference at the headend, you can detatch and move it to a better location.

[Link: remotecentral.com]
(see the bottom of the part on URC)

So the MRF-300 will be replacing the -250 (-250 discontinued)?

MRF250 will still be availible after the 300 comes out.

I have yet to try this on the MFR's but I know onthe Pronto RF Bases, all; you need to do to get them to work is put a 100 Ohm resistor in line on the Positeve side of the Emmitter(Link Cable) and you can conect directly to the IR in jack on many devices.....

Any word on whether the MRF-300 will allow Serial IR?

It will also work with MRF's

I don't believe the MRF-250 is going to be discontinued. The MRF-300 is supposed to be a "higher-end" RF receiver, due to it's multi-antenna capabilities. URC likes to blanket the market with options at various price points, so that there is something available for various budgets and needs.



Thank you,
Damon DG
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Control Systems Consultant & Programmer