Shaun Merrigan's Information Pages

Ebay IC Tester Instructions Update

Posted by Shaun Merrigan in Tech. Comments Off on Ebay IC Tester Instructions Update

14th November

Ebay IC Tester Instructions Update: Several years ago I posted the instruction and datasheets that came with the ubiquitous, generic Ebay IC Tester. These can be found here.

This post updates the original datasheet with new information: The datasheet with the tester indicates that 5v is the upper limit for zener diode testing, but recently tomtektest discovered that the unit can test zener diodes up to about 50v reliably. I dug into my parts bins and confirmed his finding using a range of zener diodes up to 48v. This is welcome information as it gives the tester additional usefulness in testing a much larger range of zener diodes.

Thanks for reading.

Shaun Merrigan

RIFA Safety Capacitor Failures

Posted by Shaun Merrigan in Electronics, Restoration, Test Equipment. Comments Off on RIFA Safety Capacitor Failures

13th November

RIFA Safety Capacitor Failures have been documented by many of us who restore and maintain vintage electronics equipment. One very spectacular failure was caught live here: courtesy Dave Jones of the EEVBLOG. These capacitors were widely used in test equipment manufactured during the late 1980’s through the 1990’s. The general consensus is that the capacitors fail because the outer case (presumed to be a type of epoxy) develops cracks which allows moisture to penetrate into the body of the capacitor. This leads to internal short circuits which cause the capacitor to fail catastrophically. Because these capacitors are line to ground, they could see line voltage whenever a piece of equipment is plugged in, even when switched off. The crack network can develop to the point where large pieces of the outer case spall off, exposing … Read More »