WEN H. KO 
1143 
involves many disciplines, requires higher tech- 
nology and a longer time. Support in this area 
should be encouraged. 
SUMMARY 
This article has discussed the advantages, 
limitations and problems in implant telemetry 
and stimulation. Several micropower telemetry 
transmitters, along with passive and active 
stimulators suitable for implant in small ani- 
mals were presented as examples. Transmitting 
and receiving schemes to reduce noise and in- 
terference were discussed with some pilot re- 
search. The problems of long term implant 
power supply and electronic packaging material 
as well as surgical techniques were outlined. 
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