[EdWilliams]

I bought this set as a follow up restoration to the Philips 462A I completed earlier this year, because I thought I should have a go at a VHF set.

It clearly had come from a good home; the seller said it had originally been bought by his grandfather and he was able to give me the original guarantee, advertising leaflet, operating instructions and receipt for 33 Gns dated January 1958. The case was close to unmarked.

I know that you shouldn't apply power to an old set but the seller told me he had already tried this. So I did try it out as soon as I got it home, with the result that it received nothing on MW/LW on the internal ferrite rod, and only worked very quietly with 10 m of wire connected to the rear antenna socket. Deaf as a post basically. On VHF a background hiss could be heard between stations, but when tuned to a station the reception was very quiet and completely unintelligible. The volume and tone controls were horribly scratchy. All quite promising really.

About a month later I made a start on it by taking the chassis out of the case. All components looked original and in good condition, with an undisturbed layer of dust covering everything. I attacked the volume and tone pots with switch cleaner, and also sprayed the piano key switch mechanism with the same for good measure. Then I ordered replacement capacitors to replace the waxies and the Hunts. The grid coupling capacitor for the EL84 output valve was definitely leaky as I could measure +1.7 V on the grid side of this component.

When the parts arrived I tried the set again before replacing anything. It could now receive MW/LW weakly on the ferrite rod - perhaps squirting the waveband switches had helped. On the other hand it had started motorboating on VHF. The volume and tone controls now worked properly.

I then set about replacing the capacitors one by one, trying the set each time on MW to see if improvements were being made. I clearly know little about valve circuits as my predictions about which capacitors would help were completely wrong. In the end it was C45 and C37 (Trader sheet, both 0.04 uF) which seemed to help the most. After all the Hunts and waxies were gone it was working really well, with plenty of volume available.

I then connected up the internal VHF aerial and found that FM was now working properly. I was actually a bit disappointed by this; I was looking forward to being able to bore friends and colleagues with heroic tales of FM discriminator realignment and front end valve replacement, but it didn't need this and I really cannot fault it's FM performance.

I took the old Hunts capacitors to work and measured them on a Fluke 171 DVM. Most of them apparently measured several times higher than their nominal value but two of the 0.04 uF components appeared completely open circuit.

There is still some voltage on the grid of the EL84; I asked about this on the forum and was told it was common for these valves to get a bit leaky in old age. The cathode current is actually a bit below the Trader sheet value so nothing is in danger at the moment. I will keep an eye on it. The HT voltages are all close to spec so presumably the rectifier is still reasonably healthy.

There is no hum on the set and the electrolytic can (a triple) stays cool, so I did not change these parts.

The pointer alignment against MW/LW stations was wrong and on full capacitance it did not reach the calibration dots on the dial. So I moved the pointer on the string a little. This then made the pointer alignment on VHF go even more wrong in the opposite direction, but this was fixed by slackening the screw on the gang drum, adjusting until correct, and then retightening. There were witness marks on the drum so someone had been here before!


Other than this, all I have done is polish up the knobs and give it all a good clean. The dial light was a bit flickery occasionally; I found the centre contact on the bulb had gone flat over the years so I blobbed some new solder onto it to build it up again - fixed the problem.

In truth I am not that impressed with the MW/LW performance; it's OK but I think the Philips 462A is better. What's the point of a directional ferrite rod in a heavy tabletop radio? Even on a really strong MW local station the magic eye (quite dim unfortunately) only closes to about three quarters. On the other hand the VHF performance is really excellent; very clear and undistorted with good sensitivity. The magic eye closes completely on all stations. I don't care about the lack of coverage above 100 MHz as in my opinion there is nothing worth listening to up there anyway.

I'm quite pleased with the outcome; with VHF available it's actually useful. It's a good looking thing and gathers favourable comments from others. My kids though (8 to 12) think I'm barking mad for spending time and money on something so old - I will have to concentrate more on their education and cultural development.

Pictures below.

Ed