How do I convert a GLM-100 (wired) to GLM-100E (wireless)?
My minister has a wireless receiver and a GLM-100 microphone with an XLR connector. Can I convert the GLM-100 for wireless use with that receiver?
Reply: Yes, the GLM-100 can be converted for wireless use. Basically you will cut the connector off the mic cable and solder on a connector that mates with your transmitter. Please follow these steps:
1. Cut the GLM-100 cable 4 feet from the microphone capsule. Using a wire stripper, trim off ½” of insulation. Twist the shield tightly and expose the red and white leads. Trim 1/8” off the ends of the red and white leads. That converts the GLM-100 into a GLM-100E.
2. From a vendor of your choice, get a wireless “body pack” or “belt pack” transmitter and receiver. They come in matched pairs because they must be tuned to the same frequency or channel.
You said that the minister has a receiver. It must have come with a transmitter, and maybe that is available. You could use that transmitter if it is a body-worn or beltpack type, rather than a handheld type.
3. Once you have a transmitter and receiver, note the manufacturer and model number of the transmitter/receiver. For example, Shure UT-1, AKG WMS60 or Samson UT-4.
4. Download and print the Crown Technical Bulletin # 3, “Connections for Wireless Microphone Applications”. Here is the web address of that document:
That document has a page titled “Connections to GLM-100E”. It tells what kind of connector you need in order to connect the mic to the transmitter, and it tells how to solder the connector.
Here’s an example. If you have an AKG WMS60 transmitter, get a TA3F connector (miniature 3-pin XLR connector) from an electronics vendor such as Radio Shack or www.digikey.com. As the document says, solder the mic-cable shield and white leads to connector pin 1. Solder the red lead to pin 2. Solder a jumper wire between pin 2 and pin 3.
Each transmitter manufacturer has a different wiring, so you’ll need to consult Technical Bulletin no. 3 for wiring information. If your transmitter is not listed, please call Crown Technical Support. They will find out what kind of connector and wiring are needed to mate the mic with your transmitter. Here is the web address of Crown Technical Support:
Another option is to contact the manufacturer of your transmitter, and ask them what mic connector and wiring are needed. The red lead of the GLM-100E connects to the pin that provides DC bias (positive voltage). The white lead connects to the pin for the audio input (high-impedance if available). The shield connects to the ground pin.
It might be easier just to purchase a new wireless mic system, already prewired with a lavalier microphone. Just mount the receiver close to the minister, away from metal surfaces, and run a cable from the receiver back to your church’s mixer.
For example, here is one vendor for the AKG WMS 40 Lavalier Pro Presenter System ($199):