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A new coaxial aerial socket is fitted, replacing the original two-pin socket. For additional safety the 'mains aerial' arrangement is disconnected, in case the customer should be tempted to try it in the future when receiving the British Heritage Television Service. An 'H' aerial it will have to be...


Here's the new dropper in position along with a subsidiary tag board. This had to be made up to mount the thermistor and an additional dropping resistor.

A large amount of neoprene rubber sleeves are used, both the guard the dropper wiring against heat and to protect it where it passes through apertures in the chassis.

Having seen what happened before, the prospect of the U801 rectifier valve ever doing this again in future freaks me out. I don't believe these are the most reliable of valves.

This set already has two 1 amp fuses in the live and neutral mains inputs in addition to a 3 amp fuse in the plug top. However to be on the safe side I now add a another fuse - an in-line 315mA one in the anode feeds to the rectifier.

This means that should the rectifier even get mildly overloaded in future, this fuse will blow immediately.

At last all the waxed tubulars and Hunts capacitors underneath are changed.

All the resistors are checked too. Five of them need replacement.

The chassis is now assembled above-decks. The focus coil and the LOPT are mounted. The valves are plugged in. The scan coils are connected up too, but the cathode ray tube cannot be mounted until the chassis is mounted on the slide-out cabinet section. This will have to wait until the flock-covered screen mask is restored. That's now the next job.

The old rubber screen mask is cracked - a very common phenomenon. First it is strengthened as much as possible by trickling superglue into the many cracks and then pushing them closed.


Then a flexible skin of Evostik is applied to bridge the tops of the remaining cracks. This has to be done several times over before it will conceal the cracks properly.

Finally, the mask is re-flocked.

The actual process is difficult to actually do and photograph at the same time!

However, first a special coloured adhesive is liberally brushed on. Then the nylon flock is 'puffed' on everywhere as forcefully as possible from the squeezy bottle supplied with the kit. Some of it sticks to the adhesive coating. The residue is shaken off and saved for later re-use.

The adhesive holding the flock was left to set, then the whole thing done all over again - for an even better finish.

Time to take a first look at the tube. This is cleaned. First, cellulose thinners is used to produce a highly insulating surface. Particular attention is paid to the final anode connection.

Then anti-static foaming cleaner is applied on and around the screen area (only). This is necessary to prevent later 'beam repulsion' effects whenever the set is switched on.

This is caused by a standing charge building up on the screen which cannot escape. The anti-static spray will allow it to leak away.


Two double canvas straps hold the tube to the mask - under spring loading. These (and the springs) are now washed in detergent.

Once dry, they are mounted up to the tube. The rubber mask sits underneath. It's necessary to centre this carefully against the screen aperture beneath so it looks right...

And this is the effect.

It is then decided that the appearance of the tube mask is not quite good enough. It is removed for tinting. This is achieved by a series of very light, distant puffs from an aerosol paint. Too much paint at this point would have ruined the flock. But the correct amount of paint actually adds to the appearance of the flock.

A little paint will also have the beneficial effect of better binding the flock in future. Such masks can loose some of the flock over the longer term, causing a powdery deposit on the inside of the screen glass.

Another point which fails 'quality check' is the appearance of the soldering at the tube base socket. This is removed, all the solder removed from the tags and the whole thing done again from scratch.

Otherwise, the chassis is now complete. Tomorrow, we switch on !

But first, here's something else that has been overlooked. The original loudspeaker lead found with the set was an old piece of lighting flex. This was duly replaced by period cable, but I hadn't terminated this with the correct connector to plug it into the speaker. The connection is actually to the primary winding of the output transformer, which sits on the speaker.

A suitable connector is now found in the stores and soldered on.

The story continues - click here...

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