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Hoffman Amps Forum image Author Topic: '62 JMI VOX AC10 TWIN-- Any experts out there?  (Read 13481 times)

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Offline pdf64

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Re: '62 JMI VOX AC10 TWIN-- Any experts out there?
« Reply #50 on: December 07, 2021, 03:56:16 am »
UK mains plug with its top cover removed, showing fuse
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Offline acheld

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Re: '62 JMI VOX AC10 TWIN-- Any experts out there?
« Reply #51 on: December 07, 2021, 09:27:11 am »
Solidly quaint . . .

Offline PRR

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Re: '62 JMI VOX AC10 TWIN-- Any experts out there?
« Reply #52 on: December 07, 2021, 10:46:58 am »
> Whats with the 13 amp fuse?

The original UK BS domestic electrical scheme used one high current circuit "ring main", perhaps per floor. This saved copper which was in short supply. A 13A plug fuse protected the line-cord from fire. This was not intended to protect the lamp or appliance, and you really can't fuse so close to protect an amplifier.

It was well into the 1960s (1970s?) that fuse requirements got more detailed.

Offline Rustybike

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Re: '62 JMI VOX AC10 TWIN-- Any experts out there?
« Reply #53 on: December 07, 2021, 01:48:50 pm »
Quote
The amp was a grey faceplate but yours looks a bit blue or is that just the camera?

Mine is grey too. Someone has changed the plug top in recent years and left the 13A in it. It's now a 2A and it's holding. One of my 10" speakers has been replaced with a 8" but they are paralleled. From what I can find out, there should 2x 8ohm in series. Not sure if wrong impedance will cause damage or  just reduced performance.

Offline pdf64

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Re: '62 JMI VOX AC10 TWIN-- Any experts out there?
« Reply #54 on: December 07, 2021, 02:28:26 pm »
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… It's now a 2A and it's holding. …
I don’t see there’s much question of 2A, or better a 1A fuse holding?
Note that an AC15 has a 1/2A (chassis mounted  :icon_biggrin ) mains fuse https://el34world.com/charts/Schematics/files/Vox/Vox_ac15_reissue.pdf
https://www.justgiving.com/page/5-in-5-for-charlie This is my step son and his family. He is running 5 marathons in 5 days to support the research into STXBP1, the genetic condition my grandson Charlie has. Please consider supporting him! BBC News feature  https://www.bbc.co.uk/news/articles/cm26llp

Offline pdf64

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Re: '62 JMI VOX AC10 TWIN-- Any experts out there?
« Reply #55 on: December 07, 2021, 02:43:39 pm »

The original UK BS domestic electrical scheme used one high current circuit "ring main", perhaps per floor. ….
Dunno about super large houses, but it’s typical for a single 30A ring to serve every socket (wall outlet) in the house.
I suppose in theory, boiling the kettle on laundry day with the washer and drier running, along with the numerous other odds and ends drawing power, should be close on tripping the 30A circuit breaker. But it never seems to.
https://www.justgiving.com/page/5-in-5-for-charlie This is my step son and his family. He is running 5 marathons in 5 days to support the research into STXBP1, the genetic condition my grandson Charlie has. Please consider supporting him! BBC News feature  https://www.bbc.co.uk/news/articles/cm26llp

Offline Willabe

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Re: '62 JMI VOX AC10 TWIN-- Any experts out there?
« Reply #56 on: December 07, 2021, 05:43:08 pm »
Dunno about super large houses, but it’s typical for a single 30A ring to serve every socket (wall outlet) in the house.

Are you saying there's only 1 @ 30A fuse/circuit breaker for the whole house?

Offline pdf64

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Re: '62 JMI VOX AC10 TWIN-- Any experts out there?
« Reply #57 on: December 07, 2021, 06:40:41 pm »
Dunno about super large houses, but it’s typical for a single 30A ring to serve every socket (wall outlet) in the house.

Are you saying there's only 1 @ 30A fuse/circuit breaker for the whole house?
A typical domestic ‘consumer unit’ will include a DP isolation switch for the incoming mains feed, a 30mA RCD, and maybe 6 - 10 circuit breakers, eg 5A for lighting per floor, 32A ring for sockets, 32A cooker, 50A shower, 15A garage, 20A hot water immersion heater etc.

https://www.justgiving.com/page/5-in-5-for-charlie This is my step son and his family. He is running 5 marathons in 5 days to support the research into STXBP1, the genetic condition my grandson Charlie has. Please consider supporting him! BBC News feature  https://www.bbc.co.uk/news/articles/cm26llp

 


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