Okay, so.... I bought an mrf-300 today for the following reason...

An elan z system uses 3 wires in the rj-45 connector for three different audio zones. These 3 ir wires have a common ground.

I've been trying to create an mx-3000 template for elan systems that will allow me to create a page for local control (ir only, blasted through the room's kp, whichever room the user is currently in) and pages for specific zone control. The specific zone control should work like this.

hit zone 1 on the mx-3000 -- the codes fire rf to a base, then out of line 1, which is spliced to the zone 1 ir wire and common ground of the elan.
the same applies to all other zones used. ir line outs, all with a single common ground.

While trying to do this with the mrf-250, I found that, although I output only on line 1, the mrf-250 seemed to short the signal to the other lines anyway. I plugged in flashing emitters and tested to see if there was a problem with the ir routing. There is not. But when splicing the wire directly, the signal somehow feeds back into the mrf-250 and ouputs on all lines. I tried controlling this with diodes and lifting the ground on a couple of the lines, without success.

So today, I used this as an excuse to justify buying myself the mrf-300. I left the mx-3000 program the same, and assign the 300 to the right rfid. I spliced the wires in exactly the same way as with the mrf-250, and tried again.

With the mrf-300 basestation, the system works perfectly! no interference between the lines, so the 300 is internally different in the way it handles the ir ground, I believe. This difference matters, I think, in any system that that uses a common ground for multiple ir inputs. (Like the hk zone 2 ir plug?)

There's my victory for the day, and I thank URC for a good product.
Just thought I'd share.
For those with questions:
Yes I checked that I was not on id0 on the mrf 250
The mrf250 version I used was 1.0, but I think they all are.

Tippy-tie,

It may not have worked because you need a resistor in the line with the MRF-250, in order to go direct to anything. It's possible, but requres that mod. The MRF-300 was designed specifically to go direct. :)



Thank you,
Damon DG
= = = = =
Control Systems Consulting, Sales & Remote Programming

thanks for the tip. What amount of resistance is needed?

Tippy-tie,

I'm not 100% certain, but I believe it's 100. You may want to double check with Eric Johnson or URC support, just to be safe.



Thank you,
Damon DG
= = = = =
Control Systems Consulting, Sales & Remote Programming