RESTORATION OF A 1959 BUSH TV85                                                                                                 Page 3


Before mounting up the tube, I decide to take advantage of the current excellent access to the so-called 'Bush Button' assemblies.

The actual plastic buttons and their actuating arms had already been removed, to keep them safe during the manhandling of the chassis during restoration. I first clean them properly. Here are the various parts after cleaning.


And here they are after assembly. There is one long screw and one short in each, securing the arms to the buttons. I soon learned that it was important which way round they went. The end of the long screw acts as a positional lock for the brown plastic sleeve.

The buttons must be mounted to the set in the arrangement shown, with the ITA ones to the left. Not well shown here, but the "ITA" marks were somewhat worn and required some light restoration - so clearly this set was mainly used to watch ITV !

After this picture was taken, the button assemblies had to be taken apart again so they could be fitted in position on the set.

Before the tube goes on, now is a good time to remove the screen and open up the tuner.

Here I apply some Waxoyl to the sliding contacts of the Band I/Band III switch with the end of a screwdriver. It's important not to let this stuff get anywhere else inside the tuner or its alignment could be affected !

Talking of Waxoyl, I also use it to recondition the cushioning rubber that goes round the front of the tube !

The tube then goes back in.

It proves a bit of a balancing act as I have to manipulate the cushioning rubber at the same time, all without stressing tube neck. Something I only want to do in the workshop, not in the customer's home !

Here's another view, from the rear this time. Can't be long now before I switch her on...


The next morning I switch her on for the first time !  Before I do, I set some Avo probes onto the tube heater. This will serve as a rough check that nothing is seriously amiss with the heater chain and, since they are all connected in series, the current going through them.

Once the set is running I also check the HT coming out of the metal rectifier. It proves to be fine, so I was right to leave this rectifier in place.

The set is now run up slowly through the Variac. After some fiddling with the ion trap magnet, this is what I see in the mirror.  A raster of sorts already !  That can only be good news...

... but I'm finding it hard to adjust the width. Here's the width coil inside the LOPT box. It's jammed. A gentle push on the core and a little WD40 soon does the trick.

By now I am seeing a picture on the screen. But you'll have to wait until the next page until you too can have a look !

I'm finding the line hold is locking rather near to the end of the travel of the control. Bush have thoughtfully provided an adjuster to correct for this. It's the little variable capacitor pointed to here.

To assist this operation, the service sheet talks about disabling the syncs by shorting out a resistor. This is a bit fidddly to reach so I decide to cheat. I cut down the signal going in at the aerial by 18dB instead, and this weakens the lock. The adjustment goes to plan.

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