Teardown: cheap (no name) compact fluorescent lamp

Teardown: miniature voltage tester

I've bought this miniature voltage tester in 2001 for a equivalent of $1. Similar tool is now available at dealextreme for $4.30.

It has flat screwdriver head, but it is quite fragile and I believe it would broke quickly if high torque would be applied, so you will need real screwdriver anyway.

It works in a similar way to classic neon lamp voltage indicator, but instead of single finger contact it has two, one for direct measuring and one for detecting voltage without physical contact. It is not as sensitive as battery powered indicators, finding wires in the wall is rather difficult if not impossible.

 Quite easy to open: my unit was not clued.

 The trick behind this simple tester is thick film resistor circuit.

Teardown: Tatarek 12V, 400mA power adapter

Classic, heavy and solid power adapter with transformer and 7812 regulator.

6VA transformer = proper power for specification. One small power supply I've used melted under full load.

Teardown: Casio TC-530 cordless phone with answering machine

 MC13109A

 Phone line adapter

Handset accu

 MC13109A again

 Two microphones directed at slightly different angles - probably noise cancellation

 Both handset and base are easy to disassemble and reassemble. Nice touch is number of screws holding particular PCB printed as silk screen layer.

Teardown: ELEKTRONIKA MK66 calculator

Vintage scientific calculator made in USSR with vacuum fluorescent display (VFD). Powered by 3xAA or external adapter.

4.5V, 0.45W

VFD up close - it's little dark in daylight (may be effect of limited VFD lifetime), but it is very impressive that this calculator is still working.

Calculator uses only single integrated circuit which is again quite impressive - this IC contains both logic circuits and high voltage VDF driver.

 VFD DC/DC converter.

 Transformer construction is quite intersting.

  Whole PCB.