SON Thorn Beta 5, gear
Sometime in mid 2017 at work we were driving around Telford trying to find the location of a column we were requested to attend to. During the drive round the area, we were approaching a top entry Beta 5 with a shallow bowl. Finding this unusual, I had a closer look, and was rather shocked to see the lantern was geared for SON lamps. At the time, I didn't have a contact for the area, so all I could do was save the location on my PC, and then almost ended up forgetting about it. 

Fast forward to just after Christmas, I brought up this lantern to a contact I had established a few years previous, asking if he was aware of the lantern and if its still installed. To my amazement, he had removed the lantern a few days prior to me making contact, and after a discussion the results are what you see here.

Now restrictions are easing, I made the journey to meet up with my  contact to collect the lantern 4 months after its removal. He informed me it was originally him who had installed, and subsequently removed the lantern after the top entry rod rusted out completely, leaving the lantern hanging by its wires. I questioned the odd choice of the shallow bowl, however to my surprise, he informed me that's the bowl it was supplied with. I can only assume since the lantern dates to 1984, that it was old stock at the factory that was sent out after Thorn EMI parted ways, and the shallow bowl was the bowl that was requested at the time. I have to admit, the shallow bowl does mean the lantern is really quite glary, so a deep bowl will be fitted in due course.

Either way its an amazing lantern, its condition is excellent, the gear is immaculate save for the rusted area on the ballast, and when lit, it runs silent. Prior to taking these images, I removed the remains of the rusted thread and cleaned the thread of the lantern out with a tap, replaced the connector block, and reshaped the two hinges owing to both somehow being bent out of shape. I will in time fully restore the lantern to bring it back to how it should be from factory.

SON Thorn Beta 5, gear

Sometime in mid 2017 at work we were driving around Telford trying to find the location of a column we were requested to attend to. During the drive round the area, we were approaching a top entry Beta 5 with a shallow bowl. Finding this unusual, I had a closer look, and was rather shocked to see the lantern was geared for SON lamps. At the time, I didn't have a contact for the area, so all I could do was save the location on my PC, and then almost ended up forgetting about it.

Fast forward to just after Christmas, I brought up this lantern to a contact I had established a few years previous, asking if he was aware of the lantern and if its still installed. To my amazement, he had removed the lantern a few days prior to me making contact, and after a discussion the results are what you see here.

Now restrictions are easing, I made the journey to meet up with my contact to collect the lantern 4 months after its removal. He informed me it was originally him who had installed, and subsequently removed the lantern after the top entry rod rusted out completely, leaving the lantern hanging by its wires. I questioned the odd choice of the shallow bowl, however to my surprise, he informed me that's the bowl it was supplied with. I can only assume since the lantern dates to 1984, that it was old stock at the factory that was sent out after Thorn EMI parted ways, and the shallow bowl was the bowl that was requested at the time. I have to admit, the shallow bowl does mean the lantern is really quite glary, so a deep bowl will be fitted in due course.

Either way its an amazing lantern, its condition is excellent, the gear is immaculate save for the rusted area on the ballast, and when lit, it runs silent. Prior to taking these images, I removed the remains of the rusted thread and cleaned the thread of the lantern out with a tap, replaced the connector block, and reshaped the two hinges owing to both somehow being bent out of shape. I will in time fully restore the lantern to bring it back to how it should be from factory.

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Ash   [17 May, 2021 at 10:11 AM]
It uses the 220/240 taps of the ballast to discharge across, so the tap would be at 1/10th or so of the winding - rather than 1/5 in modern ballasts
AngryHorse   [17 May, 2021 at 11:17 AM]
Same gear they used in the original Sonpak 7

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