This is some of the Test Equipment I use

An old AVO valve tester which is virtually indispensable unless one has loads of valves and plenty of time to swap them around. It was used by Electronics Lincs to test TV valves and still got its original handbook.

This is a Marconi TF2008, one of the last analogue professional products of this type from that company. It uses transistors of course and can do most things. One really needs a counter to check exact frequency output but it has a built-in device to carry out spot checks if one isn't available. My counter is cheap and cheerful and has one significant drawback..it leaks RF so that the superb attenuator can't be increased beyond background level of the leak. To get down to microvolts requires the counter to be unplugged.

The generator has one really unusual feature. The pointer traverses to the right going from zero frequency to the top of the first band then when the next band is selected it tunes "backwards" from right to left, next tunes "forwards" from left to right and so on in 12 bands to over 500MHz. This gives you essentially a continuous tuning scale of about 12 feet in length.

I bought it in a "non-working but easily repairable" condition years ago for a lot of money. I think mine had been connected to a transceiver which had inadvertently been put into transmit mode, damaging the output of the generator. I find it nicer to use than a digital equipment but a bit fiddly when setting to exact frequencies. This is probably because I use a digital counter with too many digits.

This is my audio signal generator, a Marconi TF1370 which is authentic enough to use valves but suffers from the drawback of having to warm up.

However I can't abide an oscilloscope which takes hours to warm up and stabilize so I ditched the various valved models I had and invested in this Tektronix for which my bid of £50 was accepted, being surplus to Plessey's requirements. It's transistors warm up immediately and one can make measurements within half a minute of switching on.

This is my Line Output Transformer Tester.

The key part of all TV sets is the transformer which develops the high voltage to drive the cathode ray tube. The LOPT, as it is known, is also pressed into service to provide subsidiary voltages for many other parts of a TV's circuitry. Energy that would ordinarily just go to waste as heat is harnessed to provide things like power for the CRT's heater, voltages to drive the focus and screen grisd electrodes, and several low voltage power sources. The LOPT is very highly stressed and a typical fault is a breakdown within the transformer's windings. This is usually not an easy fault to diagnose, at least it's one that could be mistaken for an entirely different fault. The simple way to find out if a LOPT is faulty is to swap it for a new one. Unfortunately as there are hundreds of different types it would be an expensive proposition to carry stocks of all of them. One of the largest manufacturers of transformers came up with this little tester which can accurately diagnose most LOPT faults by emulating the circuitry connected to it in a way that can determine short circuits between windings, shorted turns in windings and faulty rectifier diodes in the EHT circuit. Since I started using it I must have saved many hundreds of pounds in transformers I never needed to use.

Variac's

This is a government surplus variac which is essentially an auto transformer which one connects across the mains supply to provide an adjustable source of power for testing faulty TV sets and the like.

I've had this one in the workshop for ages on loan but recently swapped it with its owner for a TV repair.

By monitoring input current, usually across an open fuse holder one can gently increase the mains voltage and check nothing nasty is afoot.

Be warned though with TV sets the degaussing posistor presents a low impedance across the imains input until after a second it gets hot and effectively disappears. As the control is turned up it is customary to pause while the posistor gets to operating temperature bedfore looking for meaningful input current.

This particulatr variac has plenty of power handling capacity unlike my previous model which I bought from Maplins which blew up after only a couple of uses.

This is another variac. It was being chucked out because the owner didn't know what it was. Inside the home made wooden case, disguised as metal, is a variac with a horizontal frame rather than the vertical type above.

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