by Neil Bauman, Ph.D.
A man explained,
About a year ago I purchased and installed the Univox DLS-50 induction loop system in my living room. I loved it. Now it has quit working so I can no longer get the sound thru my hearing aids (with t coils) or the loop receiver I purchased from you. Is there any way to test the DLS-50 to see if it is the problem, or whether the problem is with the wire that loops the living room? How do I trouble shoot this?
Since you have the Univox DLS-50 home loop system, troubleshooting your loop system is quite easy. This is because the three blue “idiot” lights on the front of the Univox DLS-50 are nifty troubleshooting lights. All three will be on when everything is working properly.
Here’s what to do (and in this order) in order to root out the problem depending on which lights are lit or not.
1. The power light (right blue light)
First, check that the RIGHT blue light is on. If it is not, the loop amplifier will not work as no power is reaching your loop amplifier.
If it is not on, then re-plug the power adapter into the wall and unplug and re-plug the power cord into the amplifier unit. If this doesn’t solve the problem, try plugging another device into the wall socket. You want to make sure there is power to the wall plug.
If there is power to the wall plug and the right blue light still doesn’t come on, then either the wall adapter or the DLS-50 itself is defective and you need to contact your Univox dealer for instructions to return it for repairs.
If the right blue light is on, go to step 2.
2. The input signal light (left blue light)
If the right blue light is on, the next step is to check whether the LEFT blue light comes on. (The left blue light can only come on if the right blue light is already on.)
The left blue light indicates whether there is a signal coming from an external device to the Univox DLS-50. The signal could be via a patch cord from a TV or other audio device or from a microphone plugged into the back of the loop amplifier itself.
If you are using a patch cord from a TV or other audio device, first check that you are plugged into an Audio out jack of the TV or other audio device, not an audio in jack. Reseat each of the plugs to be sure they are plugged in snuggly. Make sure the TV (and cable box if you have one) or audio device is turned on and that the volume is turned UP so there is an audio output signal available at the audio out jack.
Note 1: If you are using a microphone plugged into the right microphone jack on the back of the DLS-50, be sure to turn up the microphone gain control. If it is turned all the way counterclockwise, no signal will get through.
Note 2: The left blue light only comes on while there is a signal present so if you are testing a microphone, you need to keep talking into the microphone while you look to see if the left blue light comes on. If the left blue light comes on, then go to step 3.
3. The loop signal light (center blue light)
If the right and left blue lights are on, but not the center blue light, this indicates that the signal from the loop amplifier is not going into the loop.
a. The first thing to check is that the gain (volume) wheel on to the left of the center blue light is not set at “0”. If it is at “0” no power flows in the loop and thus the light stays off. If the gain control is set at “0”, simply turn it up to “3” or higher and see if that solves the problem.
b. If you are using a room loop, did you remember to strip the insulation off the ends of the wires before you inserted them into the spring clips on the back of the DLS-50? Some people forget this simple step.
c. If you still don’t have any success, and if you have an ohmmeter, check for continuity of the loop wire. If the loop wire is broken, no current can flow and the center blue light will stay off. If you don’t have an ohmmeter, temporarily try a different piece of wire and see if that solves the problem. If it does, you know your loop wire is broken somewhere and needs to be fixed or replaced.
That should get your loop system working in 99% of the time. If you still can’t get it working, phone or email me and I’ll help you. It may be that the Univox amplifier itself is at fault. This very rarely is the case, It’s almost always one of the above problems.