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Underneath the receiver unit we see two coils (arrowed). The top one is part of a filter which removes the IF at the vision detector and the bottom one gives a high frequency boost on the output of the video amplifier.

Both can sometimes be found damaged and open-circuit. Though usually the break is visible at one end and a little common sense will soon get it going again.

Both are fine on this set.


And so to the the slog of changing all the capacitors in the receiver unit, of which there are many, with a lot doing nothing more interesting than decoupling the heater chain.

This is not a 'hide-inside-old capacitor' restoration. That would have been an extra-cost option and is only really worth it with sensitive restorations on ultra-rare sets (in my opinion). Nevertheless I do my best to be discrete - for example the bright new polypropylene capacitors are hidden under black rubber sleeves. The main thing is that the job should be workmanlike.

When all the capacitors have been changed, all the resistors will be checked and replaced where necessary, using over-rated modern resistors that are about the same physical size as the originals.

With the receiver unit completed, now we turn our attention to the main unit again.

This lonely looking capacitor on the side can be easy to miss. It feeds the audio that has just arrived from the sound detector into the volume control. It is replaced.

At the rear of the chassis there are two capacitors, here seen replaced. They're part of a network that distributes the vision signal between the tube cathode and the sync separator.

The mouldy old remains of the 'Horizontal Hold' label can be seen to lower left. All such labels will be replaced toward the end of the restoration.

Here's the frame timebase component board. Beautiful though these waxed tubular capacitors may look, they all must be replaced. Even slight leaks here can cause timebase problems.

A common failure point is the blocking oscillator transformer, seen to right. Bearing out my belief that this set is a good one and has been stored in dry conditions, the windings test OK.

The green power resistors on the right are nothing to do with the timebase. They are both part of the main power circuitry and can char the board beneath if overloaded. Usually this is caused by a leaky series capacitor. Then you can have a horrible fire risk developing !

Again, all is well in this case. If the board had been damaged, it would have been wise to mount the replacement resistors above deck for better cooling. There's invariably some 'darkening' on the chassis parts immediately above these resistors which at this stage can be conveniently removed with thinners. It's also a good idea to undo the two securing screws and look behind the board, to clean it there too and check all is well.

Once again, here's another board well worth looking behind. This is the main tag board. It will mean temporarily disconnecting three wires from its front edge....


And here's what we see. Another couple of capacitors and a power resistor. This hidden upper side of the board is invariably dirty too, and will have to be cleaned.

This won't take too long. Just be grateful it's not a Bush TV1.   On that 1948 model the hidden areas really are time-consuming to get at and service.


Although most capacitors are simply being replaced as discreetly as possible so they reasonably well 'merge in', those bearing date stamps are more sensitive and I shall try to preserve them. Here's one example - the 2µF boost rail reservoir capacitor - in bits. It wouldn't drill out so had to be split with a hacksaw.


The new capacitor is hidden inside and everything reassembled around it. Small grommets go in at the ends and these are sealed with araldite then left to set. The cable ties are temporary and ensure everything sets nice and tight.

When the capacitor is remounted in the set, the seam will be below and invisible. Naturally, I've made sure the 'APR 51' marking is opposite to the seam and will be displayed uppermost.


Here's the underside with the wiring cleaned and the capacitors changed. The power choke on the lower right is skew-whiff because it's still unbolted pending re-installation of the line output transformer.

Next all the resistors are checked. The only one requiring replacement is the 1.5 Megohm screen grid resistor on the sync separator (arrowed).

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