I have one of these erasers:
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in which the timer board has been completely disconnected from the internal wiring. Unfortunately Xeltek - who acquired this product line from Ango - will not provide the internal connection information, suggesting only that the unit should be returned to them in the US for "repair". The cost of this would exceed that of a new device. The distributor here in Australia does not have this information either.
Does anyone in this group have one of these erasers?