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A quick look at the scan coils reveals that quite a bit will have to be done. Apart from re-stuffing the line coil coupling capacitor (which will be in a very visible position) all the rubber wiring will have to be replaced. This leads to a multipole connector at the far end (not shown here).

It's worth noting that the pins on this multipole connector must be cleaned, as must the socket contacts it plugs into. If you don't, this is a common source of problems on the scans.


A quick tug in the vice removes the inner cables....


... and new rubber wires are inserted. I don't have a yellow though and substitute this with green. You won't tell anyone will you? ;-)

New neoprene sleeves at each end complete the job. It looks pretty original.




I remove the line coil coupling capacitor for re-stuffing and underneath what do I find? Another date !

So it now looks like this set must be a 1952 model, not a '51...

Once the scan coil assembly has been finished - it looks great - the line output transformer is mounted and wired up below decks.

New mounting clips are made since the originals are rusty and unsightly.

When it comes to installing the new EY51 EHT rectifier I find I'm out of stock !  So for now I've installed a new U25 - and wound 8 turns on top of the original heater winding (with insulation) to obtain the correct 2 volt supply. This mod can be easily reversed later if required.


This is the ion trap magnet which goes on the tube neck.

The original surface is being restored using a little bleach followed up thinners. On no account use something like fine wire wool on a magnetic part like this or you'll never get all the bits off...


Now it's time to test all the valves, replacing them when necessary. The first one is the PZ30 twin rectifier valve. The emission tests as excellent on both sections. The heater-cathode insulation is good too. This is most important.

The valves are cleaned with glass cleaner, being careful not to remove the markings. The valve pins are rubbed with WD40 and the appearance of the base colllars restored with an automotive vinyl surface dressing.



The PL38 line ouput valve tested fine too. These two valves live inside a screened housing along with the line output transformer and this is now reassembled.

All the remaing valves tested good apart from one EF91 in the RF/IF strip.

A repro label of the correct design will later be stuck on the rear of this housing.

In the past, in demanding applications where good ventilation is an issue, I have been known to leave this can stripped back to a minimum presence, just supporting the final anode EHT lead going to the tube.

An example of that would be the two sets supplied to the National Media Museum, which were to be left working all day, every day. In that case I even included fan cooling. But these were console versions of this set with a larger cabinet. In the TV22 there is bakelite close by, and the housing serves to protect this from the heat to some extent.

The focus lever on this set was largely missing with only a bit of it remaining. . Fortunately the same part on another TV22 (in rougher condition and not being restored) which belongs to the same customer, is perfect. The two are swapped over. New 6BA cheese-head screws are used to mount.


By now the bench needs tidying quite badly as the everything is finally assembled up... Not sure about the new red EHT lead. I think I will have to shorten this later when I know how the tube will finally sit.

Next will come the new labels, and then the set can be fired up for the first time. Labels are best printed onto cream paper and over-coated with "Transpaseal" or similar clear film.

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