JP1 Remotes

I ended up buying one of each of these and have programmed them via JP1 with KM and IR.exe. I like the extra buttons on the 8810 but hate the button layout much preferring that of the 15-2117. Add to that the fact that the 15-2117 feels so much better in my hand and I'd love to return the 8810 and keep the 15-2117, but I find I really, really need those extra 4 buttons. I don't mind the double keypress with the 15-2117 to do shifted functions, I find that easier than trying to dig my nail into the recess of the 8810 to get at the set button.

The biggest reason though and this is why I'm asking because I'm wondering if I just perhaps got a bum 8810, is the IR signal strength difference I see between the 2 remotes. With the 15-2117 as long at I'm pointing it away from me and towards the side of the house with all my equipment, everything works. With the 8810 I practically have to sight it and point it directly at the unit I want to control to get the remote to work. Both have brand new batteries from the same package so that can't be the issue.

Can other folks who've tried both offer helpful comments and/or suggestions?

PS: I also got the RS LCD 15-2107 but don't like the vertical arrangement for play/record/ffwd/rew at all although it seems like it sports the most buttons of all of the remotes I've tried. Its just big enough that using it one handed is uncomfortable. Anyone want this before I go to the trouble of returning it to the RS on the other side of town since its a discontinued model that only was 20 bucks?

PPS: Also tried the RS branded Kameleon (sp?) when I was picking up the 15-2107 and absolutely hated the feel of it in my hand.

bsoplinger wrote:I find that easier than trying to dig my nail into the recess of the 8810 to get at the set button.

Use the extender and map the "shift" key to some other key. You'll find shifted functions are then much easier.

bsoplinger wrote: The biggest reason though and this is why I'm asking because I'm wondering if I just perhaps got a bum 8810, is the IR signal strength difference I see between the 2 remotes.

The 8810 signal strength ought to be just as good.

Most recent signal strength problems reported here seem to be caused by the position of the IR LED within the remote. People have gotten good results by opening the remote and bending the leads of the IR LED so it sits a bit further forward (then reassemble the case).

johnsfine wrote:

bsoplinger wrote: The biggest reason though and this is why I'm asking because I'm wondering if I just perhaps got a bum 8810, is the IR signal strength difference I see between the 2 remotes.

The 8810 signal strength ought to be just as good.

I believe the 2117 use 2 IR LED's vs just one on the 8810. That would account for some of the difference. Also, as John stated, the LED on the 8810 might be in just a bit too far to get a good angle. Pushing it out slightly can help a great deal.

The 15-2117 does indeed use 2 IR-LEDs, which are housed behind a wide angle "window", whereas the URC-8810 uses a single IR-LED which is housed in a tight fitting hole which prevents much of it's wide angle range.

So I would totally expect the 15-2117 to have much better performance.

You can improve the URC-8810s performance by pushing the IR-LED further through the hole but it will never be as good as the 15-2117.

Could one add an LED to the 8810 by drilling another hole in the case and soldering in an additional LED.

Do you have the specs on these LED's? Are they availale?

What do you plan to solder the LED to?

LED's don't work very well in parallel. Two LED's are normally used in series. In a non learning remote you probably could cut one lead of the LED in order to insert another in series. But the voltage drop across the second might make that simple method fail (depening on how the voltage/current to the LED was regulated in the original design). You might need to change a resistor value in order to double the voltage across the LEDs.

It's even trickier in a learning remote. In the two-LED learning models, one LED is used for both transmit and learning, another is used just for transmit. I'm not sure how you'd wire a second LED into a one-LED design to match that.

Note the schematic files for RCU810 vs. 15-2117 at
http://www.hifi-remote.com/files/

Look IR1 on both (that is the learning IR LED). Now notice that IR2 (the non learning IR LED) in the 15-2117 is not directly in series with IR1. It is on the opposite side of Q1. That keeps it from interfering with learning.

Notice also that R55 is 1.6 OHM in the 15-2117, doing the same job as R7, which is 5.6 Ohm in the RCU810. Unfortunatelt, the resistor is in a different position and Q1 is different, so I can't determine whether the difference between 1.6 Ohms and 5.6 Ohms is entirely due to the difference of having one vs. two LEDs.

I don't know what the vacinity of Q1 looks like in an 8810. I expect a two-LED mod of the 8810 could be done (without hurting learning) by puting the new LED on the other side of Q1 from IR1 and maybe changing the series resistor. (But remember I'm a software engineer, not a hardware engineer).

Hmm...may just have to scarifice an 8810 in then name of science.

Just wanted to chime in here. My version of this dilemma can be found here: http://www.remotecentral.com/cgi-bin/mb ... d.cgi?5063