22 Aug 2007, 01:49
Unlike modern RC watches that have internal antennas, the Mega 1 has its antenna in the leather strap.
Out of curiosity, I disassembled a worn-out strap. Here are some photos:
Left: Antenna (outer side) and heat shrink tube; right: inner side
The capacitor required to complete the resonant circuit is under the black epoxy blob (visible on the right photo because the epoxy is worn off).
The antenna core is made of 30 sheets of amorphous metal, each about 20 micrometers thin. The antenna coil is wound around the core at the narrower part in the middle.
All this is covered with black heat shrink tube (removed for the photo).
The pictured antenna is still working!
Antenna connector on an intact strap (model 026/0010); note that the 3rd hole contains no contact.
Antenna connector on watch case (model 026/0012). The outer pins are welded to the case (the right pin makes no contact with the starp, I don't know what it is for). The middle pin is isolated and goes into the case where it contacts the module.
The leather strap antenna has always been the weak point of the Mega 1. It tends to break if bent too often and to hard, and it doesn't like moisture or sweat. Replacement bands are still available.
(Yippiee, I finally mangaged to use imageshack thumbnails WITHOUT annoying online poker popup
)
Out of curiosity, I disassembled a worn-out strap. Here are some photos:
Left: Antenna (outer side) and heat shrink tube; right: inner side
The capacitor required to complete the resonant circuit is under the black epoxy blob (visible on the right photo because the epoxy is worn off).
The antenna core is made of 30 sheets of amorphous metal, each about 20 micrometers thin. The antenna coil is wound around the core at the narrower part in the middle.
All this is covered with black heat shrink tube (removed for the photo).
The pictured antenna is still working!
Antenna connector on an intact strap (model 026/0010); note that the 3rd hole contains no contact.
Antenna connector on watch case (model 026/0012). The outer pins are welded to the case (the right pin makes no contact with the starp, I don't know what it is for). The middle pin is isolated and goes into the case where it contacts the module.
The leather strap antenna has always been the weak point of the Mega 1. It tends to break if bent too often and to hard, and it doesn't like moisture or sweat. Replacement bands are still available.
(Yippiee, I finally mangaged to use imageshack thumbnails WITHOUT annoying online poker popup
)