I tried to learn the IR codes - the remote said "success" after a few tries but it works poorly. The power sequence seems to repeat so the box appears to turn on briefly and shut off. The up channel button is the only one I got to work. I thought one of the VCR or other zenith preprogrammed codes might work as I really only need power and channel up/down but none of them seemed to work so I tried learning. Am I going to have to resort to JP1?

01414 should work. Power and channel up/down are 00053, 00181 and 00185.

I found that code 01414 works great after finding this info:

[Link: hifi-remote.com]

Update: Thanks mdavej. I didn't see your post until after I tried it. Good to know that is the right one.

Before resorting to JP1, you may want to try a few troubleshooting steps to see if you can get your remote working better. Some things you can try include:

Resetting the remote and trying to learn the codes again.
Checking the batteries in the remote to make sure they're fresh and properly installed.

Moving closer to the device you're trying to control to see if that improves the signal.

Checking the device itself to make sure there aren't any issues with the IR receiver.

If none of these steps help, then JP1 may be a good solution. Just keep in mind that it can be a bit complicated to set up, so you'll need to be comfortable with technology and willing to invest some time and effort to get it working properly.