Philips 830A condensers

[Girlmeg]

Anyone with advice on replacing 2 smoothing capacitors that are mounted along with other capacitors in a sealed box which is mounted over a good on chassis top surface. I can only see one connection tag for each on the bottom of the box and I think that this is negative tag. What wireless it is mind. Just amazing to me, very much a beginner.
Kenneth

[Station X]

If you want to preserve originality you'll have to "restuff" the can. ie unsolder the connections, remove it from the chassis, open the can (don't ask me how), remove the guts and fit new capacitors inside. If you replace the smoothers with electrolytic types, make sure to connect them the right way round observing polarity.

As far as I can make out C16, C13, C7 and C12 have one side connected to the can which makes electrical contact with the chassis. C17 and 17 are connected together inside the can. Note that the circles on the drawing represent tags, not capacitors.

Alternatively dispense with the can and fit new components on a piece of tag strip.

[Sideband]

Originally Posted by Station X

If you want to preserve originality you'll have to "restuff" the can. ie unsolder the connections, remove it from the chassis, open the can (don't ask me how), remove the guts and fit new capacitors inside.

If it's similar to the one I did in my 274A you will see that the bottom (or possibly the top) of the can is soldered to the sides. Very unlikely you will be able to use a soldering iron to unsolder the seam.....too much metal and not enough heat. You will have to use a portable blowtorch or a gas ring on a gas cooker. Hold the can with tongs and heat the seam evenly all the way round and you should then be able to tap the lid off with a screwdriver or something similar. You can then remove the capacitors from the inside possibly using more heat to melt the wax. Be warned that this can be a messy job. Once the contents are removed and the can cleaned, you can then fit new modern components inside. Fitting the lid back is easier and you should be able to use a normal soldering iron to do it. It goes without saying that you should make a note of the connections and what capacitors go where inside the can before you strip it all out.

[Station X]

I advise not resoldering the lid. Glue it back on perhaps with a few dabs of Silcone sealant. Then if you've made a mistake when wiring the capacitors you won't have to unsolder the lid again.

[Sideband]

Just a further comment on this 'bathtub' capacitor box. Some people have been known to saw the lid off. Personally I wouldn't even attempt such action because I think it would be very difficult to refit the lid neatly.