Philips 543A


This radio was bought at a Wooton Basset swapmeet - and initially consigned to the shed! It wasn't in bad condition. The cabinet came up reasonably well with polishing paste and a bit of elbow grease. Unfortunately, a chunk of the rear of the cabinet top had been broken off at some time. This had been glued back in by a previous owner. Not a bad repair - but not invisible.

Tending to re-inforce my long-standing prejudice (see Bush VHF62), the performance on VHF was poor. Although signals seemed to be present at good strength, clear audio could not be obtained. It was concluded that the FM i.f. needed re-alignment.

Although not having attempted this task before, I decided to give it a go. Plastic knitting needles were duly filed and the relevant cores loosened. I had previously assumed that a wobbulator was required to align an FM i.f. chain. However, a visit to Paul Stenning's excellent website told me otherwise. All i.f. transformers peaked ok - save one. On dismantling, one of the tubular ceramic 33pF capacitors was found to be o/c. This was replaced and the alignment completed successfully, including setting the ratio detector.

Unfortunately, after all this effort, the audio was still as distorted as ever! It eventually dawned on me that the oscilloscope trace that I had been staring at for the last couple of hours whilst peaking the i.f.t.'s had had audio on it - and the scope probe was across the 10uF discriminator capacitor! Once the penny had finally dropped, the capacitor was quickly changed for one that actually had some capacitance and good audio was restored. A salutary tale - you only see what you want to see!


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