It’s time for another CRT-based post! This time it’s a Matsushita 40CB4-based viewfinder from 1980. These came from JVC colour tube cameras, and are physically massive! I’ve already worked out the pinout on the multicore cable here & attached a usable connector. There’s lots of information on the bottom label
Following on from the viewfinder teardown, here’s the rest of the camera. This unit dates back to 1980, and is made almost exclusively of cast aluminium. Very little plastic has been used here & only for the bits that the user comes into contact with. This camera is based around
The other day at the local canal-side waterpoint, this TV was dumped for recycling, along with another later model Colour TV. This is a 1970’s Black & White mains/battery portable made by Thorn. It’s based on a common British Radio Corporation 1590 chassis. Having received a soaking from rain, I
Here’s a small flyback / Line Output Transformer from a portable colour TV set. Usually these transformers are vacuum potted in hard epoxy resin & are impossible to disassemble without anything short of explosives. (There are chemical means of digesting cured epoxies, but none of them are pleasant). This one
Continue readingCRT Flyback / Line Output Transformer Destructive Teardown
I have found myself needing some more in the way of High Voltage supplies of late, with the acquisition of the new He-Ne laser tubes, so I went trawling eBay for something that would be suitable to run these tubes. (I currently only have a single He-Ne laser PSU brick,
Here’s another Sony Flat CRT TV, the FD0280. This one was apparently the last to use CRT technology, later devices were LCD based. This one certainly doesn’t feel as well made as the last one, with no metal parts at all in the frame, just moulded plastic. Being a later
Here’s an oddity from the 1980’s – a CRT-based portable TV, with a very strangely shaped tube. Sony produced many types of flat CRTs back in the 80’s, with the electron gun at 90° to the curved phosphor screen. The front panel has the display window, along with the tuning
Looking through eBay recently I came across a great deal on some Helium-Neon laser heads from Melles Griot. While definitely not new, these gas lasers are extremely long-lasting & I figured the tubes inside would make a nice addition to my laser collection. Doing some searching on the model number,
Continue readingMelles-Griot 05-LHP-141-15 Helium Neon Laser Head & Tube Extraction
Power for a He-Ne laser is provided by a special high voltage power supply and consists of two parts (these maximum values depend on tube size – a typical 1 to 10 mW tube is assumed): Operating voltage of 1,000 to 3,000v DC at 3 to 8mA.Like most low current
Putting Together a Demonstration He-Ne Laser For a classroom introduction to lasers, it would be nice to have a safe setup that makes as much as possible visible to the students. Or, you may just want to have a working He-Ne laser on display in your living room! Ideally, this
Instant He-Ne Laser Theory The term laser stands for “Light Amplification by Stimulated Emission of Radiation”. However, lasers as most of us know them, are actually sources of light – oscillators rather than amplifiers. (Although laser amplifiers do exist in applications as diverse as fibre optic communications repeaters and multi-gigawatt
Continue readingTheory of Operation, Modes, Coherence Length
As with *any* laser, proper precautions must be taken to avoid any possibility of damage to vision. The types of He-Ne lasers mostly dealt with in this document are rated Class II, IIIa, or the low end of IIIb (see the section: Laser Safety Classifications. For most of these, common
A helium-neon (henceforth abbreviated HeNe) laser is basically a fancy neon sign with mirrors at both ends. Well, not quite, but really not much more than this at first glance (though the design and manufacturing issues which must be dealt with to achieve the desired beam characteristics, power output, stability,
Here’s a quick teardown of an ignition transformer, used on gas fired ovens & hobs. This unit takes mains 240v AC & uses a transformer to step the voltage to several kV, at a low current to ignite the burners. The transformer section is completely potted in Epoxy resin for
This detector has now been retired from service since it’s a fair bit out of date. So here’s the teardown! Unlike older detectors, this unit has a built in battery that never needs replacing during the life of the sensor, so once the unit reaches it’s expiry date it’s just
Continue readingFire Angel CO-9D Carbon Monoxide Detector Teardown
Here are a few details of a valve amplifier I am building, using the valve related parts from a 1960’s reel to reel tape recorder. This amplifier is based on an a Mullard ECL82 triode/pentode valve, with an EM84 magic eye tube for level indication. Here the first components are
Continue readingDIY Valve Amplifier – Part 1 – Amplifier Section
Here is a cheap no frills microwave oven, which died after a few weeks of normal use. Cover removed, showing the internals. Front of the microwave is on the left. Closeup of the timer unit. Cheap & nasty. Magnetron removed from the oven. Antenna is on the top, cooling fins