Inexpensive Options for Assistive Listening Device Receivers
If your church or organization uses a hearing aid system to help members listen to the sound system, you might be looking for a low-cost alternative for some or all of the receivers used by that system.
This page explains a relatively inexpensive method of adding receivers to a wireless FM system. There are other types of systems, such as infrared transmitters or inductive loop systems. The information on this page will not help you with those types of systems. This information applies only to wireless FM systems. You can quickly tell if you have a wireless FM system, because the transmitter, which is hooked to your sound system, will have an antenna. Most commonly, this is a telescoping whip antenna. This unit serves as the transmitter for a very low power FM radio station. The signal is picked up by the receivers used by individual members in the same way that a normal FM radio works.
These systems are known as Assistive Listening Devices or Assisted Listening Devices (ALD). Their official name under FCC rules is "Auditory Assistance Devices", or "Auditory Assistance and Simultaneous Translation Devices." They are used as assistive listening devices for hard of hearing members, for simultaneous translation in other languages, for descriptive audio services, and for other purposes. Typically, the hearing-impaired member is given a small receiver with a pair of headphones. He or she can turn up the volume as loud as necessary to hear, without disturbing others. Sometimes, these are simply called church wireless hearing assistance systems, or simply wireless hearing aids.
Here are some common systems for which the instructions on this page will work:
The Hamilton system is relatively new to the market, and represents a low-cost alternative to the more expensive systems available previously from Williams. The Hamilton system operates on Willaims Channel F (75.5 MHz), meaning that the receivers should be compatible, as long as you can switch your Williams transmitter to Channel F. If you're looking for low-cost additional receivers, the most economical option for adding on to your Williams system might be to purchase the Hamilton system. This would result in an additional transmitter, which you could set aside as a spare, or perhaps use in a different part of the building.
You can purchase additional receivers for these systems. For example, the following receivers are available on
As you can see, buying even one of these receivers can be quite expensive if you're on a tight budget. This page explains some other options that might be available. There are a number
It should be noted that some of the ALD receivers are specially designed to interface with a user's own hearing aid. For example, some of them are designed to electronically deliver the sound to a user's cochlear implant. In general, the solutions shown on this page will not have that same functionality. However, the user might have his or her own equipment to hook the hearing aid to a radio headphone jack, in which case the solutions on this page would work.
These systems operate in the same manner as a standard FM radio station, with two differences. First of all, the transmitter obviously uses much lower power. A typical Assistive Listening Device (ALD) transmitter puts out about 0.02 watts, in comparison with the thousands of watts used by a radio station. Since the necessary range is typically confined to the interior of a single building, this is normally not a problem, but it does mean that the receiver needs to be fairly sensitive. And obviously, the receivers shown above are sensitive enough to serve their intended purpose.
The other difference is the frequency that is used. As you probably know, the standard FM dial is marked 88-108, meaning that it covers the frequency range of 88 through 108 MHz. All FM radio stations in the United States, Canada, and most of the world use this range. Therefore, you cannot use a standard FM radio to listen to your ALD transmitter, since it doesn't tune down low enough on the dial.
There are, however, two options available. First of all, there are a few countries that use a different FM dial, and the frequencies used in those countries actually overlap with the ALD frequencies used in North America. Therefore, if you can get your hands on one of the radios intended for use in those foreign countries, you can use it as an ALD receiver.
In Japan, the FM band extends from 76.0 - 90.0 MHz. And the old FM band used in Russia and some other Eastern-Bloc countries (the "OIRT band") was 65.8 - 74.0 MHz. That band is being phased out in Eastern Europe in favor of the U.S. band. But it is still in use, and receivers are still being produced.
These receivers are readily available in the U.S., if you know where to look, and their availability will be discussed below.
The following frequencies are used by Williams Sound for their systems:
Channels A through H are the most commonly used, and many older units will cover only these channels. Because these frequencies are established by the FCC, almost all manufacturers will use these same channels, although mot of them will not use the same letter designations.
You will need to determine which frequency your system is using. On some of the more expensive transmitters (such as the Model T35), the until displays the information whenever it is turned on. On others, you might need to consult a sticker on the unit or the instruction manual. You can also look at your existing receivers and see if they are marked with the receive frequency. You can also use trial and error, and just tune through all of the channels.
You will need to find a receiver that receives this frequency. In most cases, the best way to do that will be to obtain one of the radios intended for use in other countries, as discussed below. Another option that might work, however, is to use an old (pre-2009) TV sound radio.
Until American TV switched to digital in 2009, the TV sound was transmitted in exactly the same way as FM radio. Therefore, there were available on the market many cheap radios that could pick up TV sound. These radios no longer work with digital TV, but they will still pick up ALD sound. The ALD frequencies are all located between channels 4 and 5. Therefore, if you have one of these older radios, you can use it to receive the ALD signal. Simply tune it between channels 4 and 5 until you hear your transmitter.
Even though these radios no longer work for their intended purpose, they are occasionally still being advertised and sold
for that purpose. For example, the following radio available on Amazon is (incorrectly) advertised as being able to receive
TV sound. It will not do so, but it will pick up the ALD signal:
A more likely place to find such radios is thrift stores or even eBay. If your church or other organization has ever had a garage sale, then chances are one of these radios passed through your hands. Millions of them were made, and there are many in good condition still available.
Before investing too much money in this type of radio, though, keep in mind that it might not work particularly well. Many of these radios were not particularly well made. They were adequate for picking up the strong signal of a TV station, but they might not do a very good job of picking up the very low power ALD transmitter. But since the price is often right (zero, or close to it), it's probably worth a try.
As a general rule, a radio with an analog dial will not perform as well as one that tunes digitally. This is not an absolute rule, but it will be true the vast majority of the time. Almost all of these radios have an analog tuning dial, and they will probably not be particularly good performers. But they might work in some cases.
The discussion below involves a certain amount of speculation on my part. I haven't tested any of the radios listed, and
I can't say for sure how good they are. I'm making my best guess based upon my reading of their specifications, and product
reviews that have been posted. My gut reaction is that most of the digital radios shown below will work quite well, and that
the analog radios will perform to some extent, although not necessarily well. There are only two radios where I can
personally vouch as to their ability to do the job. My church has a Williams Sound system, and I've used both of these
radios, and they receive the signal well. When my kids were in the nursery, I used one of these myself, and could hear every
word of the service going on elsewhere in the building. Those two radios are the following:
As you can see, one of these radios costs a lot more than you probably want to spend. The other one is also tempting, but there's a big problem. In addition to being able to receive the ALD signal, these radios are also capable of transmitting. (Neither one can actually transmit on the ALD frequency, but they can transmit elsewhere, including on police and public service frequencies.) There is no easy way to disable the transmit function, and there is a significant possibility that someone pressing buttons could start transmitting. If they were unlucky enough to do so on the local law enforcement channel, then chances are both you and that hapless person would have a lot of explaining to do down at the station. If you can trust the person using the radio to know what they're doing, then the BaoFeng UV-5R would be an excellent choice. But it's probably not worth the risk, if you're going to be handing the radio out to persons of unknown technical skills.
(Incidentally, I'm a Ham Radio Operator, and I have additional discussions about both these Yaesu and Baofeng radios on my website and blog. You should keep in mind that if you have any Ham Radio Operators in your membership, they can probably provide you the technical assistance to get the correct receivers you need.)
Again, I have not tested any of the following. But a good quality FM radio should receive your ALD transmitter well. But remember, most FM radios sold in North America only go down to 88 MHz. You'll need one that goes down to 72, and those shown on this page should do so. It is very likely that these radios will work well, but there are no guarantees. Before incurring a large expense of buying several, it is highly recommended that you test one and make sure that it will serve your needs.
As noted above, you are most likely to have success if you use a digital receiver--that is, a receiver that has a digital
display of the frequency. All of the following radios will cover this range, and they should work well.
If you're using one of these radios as an external speaker (such as in a nursery), then you won't need anything additional. If you're using it as an additional receiver for those with hearing impairment, then you'll need to buy a pair of headphones, although in some cases, the headphones are included. Often, the easiest way to deal with this issue is to buy the headphones in bulk at the dollar store, and simply replace them when they get broken, as they inevitably do. All of these radios will take a standard "walkman" type headphone. In some cases, you will hear the sound only out of one ear. If that's the case, then you will also need the following adapter:
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