Good device with potential for improvement

First of all:
The device is essentially meeting the dots placed on it; It takes a microphone a ringtone (with phone not tested), and thus solves the play of its own signal. The microphone sensitivity can be varied, the volume and the melody of the tone. The device itself has an on / off switch. Unless it would be 5 star.

What could now be improved?

1. Before assembling the equipment has been tested to function, everything seemed fine. But mounted: no reaction. What ultimately was that the microphone while holding by hand responded at any position on the ring tone, after mounting the tape, however, directly at the site of the bell, at which was present the greatest Schallamplitue, mounted his had. This was true even at the highest microphone sensitivity.
2. The length of the microphone cable is rather short in practice. Five feet seem much, but if the cable will be clean through channels, has in me the length not even been enough to mount the amplifier itself "around the corner", but only just before it. Let alone in another room. As well has any other requirements, a modular system would be as helpful (optional 5m / 10m / 15m, etc.).
3. For a modular system were speaking also the fact that the amplifier could obviously also supplied with power adapter.
4. The batteries are inserted rather very tightly in the tray; the lid is not properly closed, they jump out easily. And the locking mechanism does not seem to me to be quite optimal.
5. The absence of a possibility to adjust the number of repetitions of the tone was, indeed mentioned several times.

In the sum of these (unnecessary) little things that annoy partly belonging in practice, I draw a star again.
About long-term experience, I can not say anything yet, the device is mounted only a week.