Edinburgh Masker

Edinburgh Maskers, Repair Service

Dave Germeyer
306 South Baltimore St.
Dillsburg, PA 17019-1011
(717) 432-3103
dgermeye@verizon.net
(Will also buy used Maskers).

"The Edinburgh Masker was developed by Ann Dewar, a therapist at the Stammering Research Unit at Edinburgh University in Scotland, in conjunction with her husband, A. D. Dewar, a physician (Dewar, Dewar, Austin & Brash, 1979). The Edinburgh Masker consists of a throat microphone (held against the thyroid prominence by an elastic strap), a small control unit that can be worn on the belt or carried in a pocket, and either two separate earpieces or a headphone set.

The masking noise is activated by phonation detected by the throat microphone; as soon as an utterance is completed and phonation stops, the lack of a throat microphone input signal automatically cuts off the masking noise. One challenge for these types of devices is individuals whose speech initiation is characterized by silent prolongations (blocks). Without input to the throat microphone, no masking is present to assist the user's speech. The control unit has a switch that allows manual activation of the masking noise for those occasions. The use of a throat microphone is an important feature for these types of devices; with a regular microphone, any conversation or environmental sound in close proximity to the microphone would cause the masking to be switched on, whether the user was speaking or not. The Edinburgh Masker reached the zenith of its popularity in the 1990s. Unfortunately, it is no longer manufactured." Larry Molt (A Brief Historical Review of Assistive Devices for Treating Stuttering, 2005

Edinburgh Masker Notes

by Dave Germeyer

Two common problems with the Masker, related to the "Remote Start" Terminals are:

a. Failure to produce noise when touching with finger.

b. Failure to turn off or making noise all the time.

These contacts tend to oxidize or become tarnished and when this happens, poor contact is established and Masker will not produce noise.

The Masker will over time, accumulates dirt or grime between these contacts which act much the same as actually touching the contacts, and produce noise all of the time.

Both problems can be corrected by cleaning the contacts and the area surrounding them with some alcohol. Alcohol Swabs available at the drugstore or medical supply house are a convenient way to perform this operation. Alcohol will not affect the case of the Masker.

Wiping the microphone and head phone plugs with alcohol may also eliminate possible intermittent symptoms.

Replacements for throat microphone:

Two (2) types of replacement microphones are available.

A true throat microphone is available and is similar to the original supplied with the Masker. A common problem with the original microphone was that the neckband would stretch and was not replaceable. The replacement does have a replaceable neckband.

Another problem was that the active element in the original microphone would slowly diminish in sensitivity over the years and eventually become useless.

This new microphone uses a different type of active element and as such, requires the use of an external power supply-i.e., 3 volts (battery). I can supply this external power supply.

An inexpensive microphone is available from Radio Shack and is more sensitive then the original throat microphone but I can supply a device which easily converts this Radio Shack microphone to one that will only perform as a true throat microphone and will not pick up or cause the Masker to respond to high background or ambient noises. As modified for throat microphone operation, the Radio Shack microphone should be secured to the throat with some type of adhesive tape-i.e., 3M 109 Scotch Removable Poster Tape (double sided), available at most grocery, drug or craft stores.

If background noise is not a problem, the microphone can be operated in its intended function (lapel mike) and secured to a person's under clothes and therefore not be conspicuous. Under these operating conditions, the Internal Sensitivity adjustment of the Masker will require a re-adjustment. This particular adjustment is adjacent to the On-Off switch, located on the Printed Circuit Board (PCB). I can supply an adjustment tool for this purpose and instructions on getting access to the internal control.

Hearing Devices

Again, for those using the Air Tube type of hearing device, I have not located any replacement for the splitter (Manifold) but the Driver units are still available. A suitable alternative to the Air Tube type would simply be using some ear buds similar to those used by Walkmans or IPods. Many styles are available and should be fitted according to person's individual requirements.

Replacement Cords/Cables

Replacement cords are available to replace those originally supplied with the Masker. No replacement cords are required for either type of replacement microphone or if ear buds are being used as both utilize their own integral cords.

Telephone Use

The Masker can be utilized when using the telephone by simply removing the handset from your ear when speaking and placing it back to the ear when listening. This is a simple but effective solution and had been proven to work well,

Volume Control

If encountering any intermittent operation when adjusting the volume control-i.e., radical changes in volume or crackling of audio noise, chances are the volume control is damaged. By design (not intentional) the volume control is fragile and a very thin piece of ceramic material breaks. I have no replacement that includes an extended shaft but can replace a broken control with one that would be mounted internally on the PCB and would require an adjustment tool (same tool as used for the Sensitive control). This should not present a problem as once a comfortable level (of volume) is established; there is no need to continually re-adjust the volume.