23" GEC dual standard receiver chassis identification

[high_vacuum_house]

Good evening,
I bought this set from the RWB auction last Sunday for £5, and I decided to see if it was going to be an easy restoration as most of the capacitors are Mullard mustard types rather than old waxies and Mouldseals. Other than a PCF80 and a PY800 down to air, running it up on the variac without doing anything else gave a near complete raster on both standards and interference on the screen when changing the 405 tuner.

Other than a handful of blue and green TCC plastic paper type capacitors, Clearing all the dust out and freeing off the UHF tuner mechanism, It looks as if it could be in excellent condition.

One thing I am missing though is that I cannot identify the set model number as this has dropped off the back at some stage. Does anyone know what the model number is so that I can find the service sheet for this receiver.
Many thanks,
Christopher Capener

[Colourstar]

Hi Christopher,

I have the 19" version here (identical cabinet) and from memory I believe it's a GEC BT455.

They are amazingly good performers so fingers crossed you've got a bargain! I assume that's the same set that was for sale on the BVWS stall at Retrotech a few months ago.

Steve

[high_vacuum_house]

Good evening,
That looks like the correct line up for this model. Its full name is the BT455DST. Hopefully I can get some results fairly soon.

Many thanks,
Christopher Capener

[thermionic]

An absolute bargain for a fiver, Christopher!

Apart from changing the usual capacitor culprits you’ve already mentioned I would dry out the over wind before running it for long. This range of models are now suffering from a cracked plastic overwind encapsulation so moisture can easily penetrate the windings.


Best of luck.

SimonT.

[slidertogrid]

It was indeed a bargain Christopher ! The chassis is the GEC 1000 series. If the overwind is white plastic and has any cracks in it drying it out as suggested is advisable.
If you are lucky the set may have the later LOPT or a replacement with a black plastic overwind. These are not usually cracked in my experience and are a better bet.
I have a nice looking Sobell version in my collection the overwind on that was duff so I have fitted a tripler. It works well.

[dazzlevision]

Originally Posted by slidertogrid

The chassis is the GEC 1000 series.

Not quite, it's the predecessor chassis to the GEC 2000/Sobell 1000 series of models.

The earlier chassis still used a PCL84 as the video amplifier and an EF80 (on the line oscillator/frame timebase panel) as the sync separator. The successor 1000/2000 chassis used a PFL200 as video amp and sync separator.

In addition, there is a separate 405-625 system switch operating lever on the right hand side of the cabinet, whereas in the 1000/2000 chassis, the is was achieved by a mechanism at the rear of the VHF tuner, operated by the VHF channel selector knob.

In most other respects, they are very similar and capable of very good performance.

[high_vacuum_house]

Good afternoon,
Just got back to it and it has the white plastic LOPT cover which has cracked. I am supplying around 35mA through the overwind via the DY86 anode cap and the PL504 anode cap. Hopefully all will be well as there is no signs that the set has been stored anywhere damp at all as all of the metalwork is bright and the cabinet finish is excellent.
I have so far carefully vacuumed all of the dust out and freed off the UHF tuner which was seized with old grease that had gone hard.

Christopher Capener