UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

EdWilliams · 5th Feb 2017, 11:52 am

Hi,

I recently posted a question on this forum about the HT voltage of my Philips 462A that I have been restoring. The set was originally given to me by my grandmother.

Although it's taken 25 years of very intermittent activity to get this far, I have now decided the set is done.

In total it needed:

General filth removal
New electrolytics
New volume control
New AZ31 rectifier valve, replacing incorrect U50
Replacement of output valve grid capacitor
New speaker cloth
Fettling of waveband switch
T cut and polish of case, repainting of 'go-faster' stripes

It now works very well. The station alignment against the dial is spot on on MW, but slightly out on LW (R4 peaks at an indicated 1495 m, not 1515). I've not touched the IF or RF alignment out of fear I could improve it backwards. MW works well on 3 or 4 metres of wire as an antenna, but I'm using about 10 m so that R4 LW is at good strength. The LW section doesn't like CFL light bulbs!

One of the best features of the set is that the glass dial is undamaged with perfect printing. Its worst feature is a crack in the case by the tone control, but you only see this if you go looking for it.

Sometime I need to find new screws for the base and back panels; these screws were missing when I was given the set and a certain amount of somebody's Meccano set was apparent.

The HT voltage with the new rectifier valve is 40 V or so lower than the Trader sheet values. Forum advice was that this could be because the Nos AZ 31 might be a bit below par. Having looked more carefully I have another theory.

I now think the set has been repaired long ago with a non-standard mains transformer. The transformer has a fuse on it not shown on the Trader Sheet diagram. Also, the voltage selector panel has been replaced by a Radio Spares item, nothing like the item seen in other examples of the set (see photos). The wiring for the transformer and voltage selector panel seems in better condition than some of the other wiring in the set, but still looks old. So I suspect the mains transformer is a generic replacement fitted when the set was still in every day use but which has a different turns ratio for the HT. With hindsight, I knew this at the start but had never put two and two together.

Anyway, the repair was done to a high standard and the set works fine. It's part of its history so I'm going to leave it.

Philips radios seem to have a reputation for complexity on this forum. I think I got lucky with this one as it only needed a few obvious component changes to get it going again.

Ed

5th Feb 2017, 11:52 am	#1
EdWilliams Triode Join Date: Jan 2017 Location: Hampshire, UK. Posts: 24	Philips 462A Hi, I recently posted a question on this forum about the HT voltage of my Philips 462A that I have been restoring. The set was originally given to me by my grandmother. Although it's taken 25 years of very intermittent activity to get this far, I have now decided the set is done. In total it needed: General filth removal New electrolytics New volume control New AZ31 rectifier valve, replacing incorrect U50 Replacement of output valve grid capacitor New speaker cloth Fettling of waveband switch T cut and polish of case, repainting of 'go-faster' stripes It now works very well. The station alignment against the dial is spot on on MW, but slightly out on LW (R4 peaks at an indicated 1495 m, not 1515). I've not touched the IF or RF alignment out of fear I could improve it backwards. MW works well on 3 or 4 metres of wire as an antenna, but I'm using about 10 m so that R4 LW is at good strength. The LW section doesn't like CFL light bulbs! One of the best features of the set is that the glass dial is undamaged with perfect printing. Its worst feature is a crack in the case by the tone control, but you only see this if you go looking for it. Sometime I need to find new screws for the base and back panels; these screws were missing when I was given the set and a certain amount of somebody's Meccano set was apparent. The HT voltage with the new rectifier valve is 40 V or so lower than the Trader sheet values. Forum advice was that this could be because the Nos AZ 31 might be a bit below par. Having looked more carefully I have another theory. I now think the set has been repaired long ago with a non-standard mains transformer. The transformer has a fuse on it not shown on the Trader Sheet diagram. Also, the voltage selector panel has been replaced by a Radio Spares item, nothing like the item seen in other examples of the set (see photos). The wiring for the transformer and voltage selector panel seems in better condition than some of the other wiring in the set, but still looks old. So I suspect the mains transformer is a generic replacement fitted when the set was still in every day use but which has a different turns ratio for the HT. With hindsight, I knew this at the start but had never put two and two together. Anyway, the repair was done to a high standard and the set works fine. It's part of its history so I'm going to leave it. Philips radios seem to have a reputation for complexity on this forum. I think I got lucky with this one as it only needed a few obvious component changes to get it going again. Ed Attached Thumbnails