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Other Vintage Household Electrical or Electromechanical Items For discussions about other vintage (over 25 years old) electrical and electromechanical household items. See the sticky thread for details. |
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10th Mar 2022, 1:58 pm | #1 |
Pentode
Join Date: Jul 2020
Location: Falkirk, Stirlingshire, UK.
Posts: 200
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Goblin electric clock model 31 Alarm - working of sorts.
Guys, recently acquired a nice Bakelite Goblin alarm clock.
Connected to a Variac and lamp limiter, it actually ran, but after 15mins the coil started to smoke on 230VAC. The clock actually runs on 140VAC, no smoke but coil still 80 degrees under the thermal imager. Windings are almost 1.2kohm, I think this works out at 44watts which is why the coil is so hot. Would any member be able to rewind (obviously for payment) or know where I can have this work carried out? Or is it easy enough to try and do. I can't locate a great deal of info so have know idea what the winding resistance should be. There are no other electric components in this clock, live and neutral just go straight to the coil. Thanks. |
10th Mar 2022, 4:26 pm | #2 |
Dekatron
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,846
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Re: Goblin electric clock model 31 Alarm - working of sorts.
10k ohms and a couple of watts is more typical.
You can rewind the coil with thicker wire very easily, then power it from a low voltage AC supply. Mike Barker or Ed Dinning are the rewinding experts here. |
10th Mar 2022, 5:21 pm | #3 |
Guest
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Re: Goblin electric clock model 31 Alarm - working of sorts.
That is lovely, the low voltage fewer turns approach is the best way to go, more copper less insulation, better coil. That coil does look very cooked.
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10th Mar 2022, 6:26 pm | #4 | |
Pentode
Join Date: Jul 2020
Location: Falkirk, Stirlingshire, UK.
Posts: 200
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Re: Goblin electric clock model 31 Alarm - working of sorts.
Quote:
I have 0.32mm enamelled copper wire, would this be suitable and how many turns would be required, I have never re-wound a coil so I have a 9VAC PSU, would that be suitable? Cheers Lee |
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10th Mar 2022, 6:30 pm | #5 | |
Pentode
Join Date: Jul 2020
Location: Falkirk, Stirlingshire, UK.
Posts: 200
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Re: Goblin electric clock model 31 Alarm - working of sorts.
Quote:
Cheers Lee |
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10th Mar 2022, 8:17 pm | #6 |
Guest
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Re: Goblin electric clock model 31 Alarm - working of sorts.
Fill the spool, then find out how many volts it needs to run and add 50% for luck. At a vague guess I would say 0.32mm filled would be 12V or so.
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10th Mar 2022, 9:48 pm | #7 |
Pentode
Join Date: Jul 2020
Location: Falkirk, Stirlingshire, UK.
Posts: 200
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Re: Goblin electric clock model 31 Alarm - working of sorts.
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11th Mar 2022, 7:59 am | #8 |
Octode
Join Date: Feb 2007
Location: Ely, Cambridgeshire, UK.
Posts: 1,976
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Re: Goblin electric clock model 31 Alarm - working of sorts.
Try these two sites.
Basic repair:- https://www.teasmade.uk/clock-faults-and-repair/ Rewinding for low voltage:- https://sound-au.com/clocks/ocm.html |
11th Mar 2022, 8:11 am | #9 | |
Pentode
Join Date: Jul 2020
Location: Falkirk, Stirlingshire, UK.
Posts: 200
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Re: Goblin electric clock model 31 Alarm - working of sorts.
Quote:
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13th Mar 2022, 9:22 am | #10 | ||
Dekatron
Join Date: Nov 2003
Location: Near Leeds, West Yorkshire, UK
Posts: 4,609
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Re: Goblin electric clock model 31 Alarm - working of sorts.
Quote:
__________________
Mike. |
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13th Mar 2022, 1:08 pm | #11 |
Heptode
Join Date: Nov 2009
Location: Scarborough, North Yorkshire, UK.
Posts: 510
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Re: Goblin electric clock model 31 Alarm - working of sorts.
Hello Mike, I showed my wife your article on "teasmade" and she couldn't believe what she read, an excellent detailed informative read. I wish I had located it before as I've fixed a couple in the past. Both needed a good clean up and away they went. ted
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14th Mar 2022, 7:56 am | #12 | |||
Pentode
Join Date: Jul 2020
Location: Falkirk, Stirlingshire, UK.
Posts: 200
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Re: Goblin electric clock model 31 Alarm - working of sorts.
Quote:
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14th Mar 2022, 8:34 am | #13 |
Pentode
Join Date: Jul 2020
Location: Falkirk, Stirlingshire, UK.
Posts: 200
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Re: Goblin electric clock model 31 Alarm - working of sorts.
Just an update on this.
All old copper removed from the coil and rewound using a paint brush with the spool wedged onto the shaft, the shaft inserted into a battery variable speed drill which was held in a vice, a cable tie around the trigger just nipped to give the speed I was happy with, spool of 0.32mm wire on a screwdriver, just let it go until the spool was full. The ohms measurement was 8.5. Connected to the Variac, set at 16VAC and it worked perfectly. So ordered a 16VAC plug in adapter, now this measured 20VAC, I assume as no load, but when connected to the clock it ran noisily and didn't work well at all, so not sure what was wrong, possibly the load is so small..?? Have ordered a 9VAC and 12VAC adapter to see if these are any better. While the clock was running happily and quietly on the Variac at 16VAC, I connected my meter across the power connections at the clock, measured 4.5VAC Any thoughts on this appreciated. Thanks. Lee |
14th Mar 2022, 9:49 am | #14 |
Dekatron
Join Date: Nov 2003
Location: Near Leeds, West Yorkshire, UK
Posts: 4,609
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Re: Goblin electric clock model 31 Alarm - working of sorts.
Probably the lack of load.
Better to have one of our members to wind the coil to 240v, Lee.
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Mike. |
16th Mar 2022, 10:47 pm | #15 | |
Pentode
Join Date: Jul 2020
Location: Falkirk, Stirlingshire, UK.
Posts: 200
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Re: Goblin electric clock model 31 Alarm - working of sorts.
Quote:
Have this actually working fine now on a 9VAC supply, I have added 2 x 100mA fuses inside the clock, just need an enclosure to house the board. Does anyone know how the alarm works? All I know is that when I turn the day / night dial a plunger pops up at 3 on the day side. The button on top of the clock when pushed depresses the plunger! I can't see what would make an alarm noise Thanks Lee |
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17th Mar 2022, 6:37 pm | #16 | |
Octode
Join Date: Mar 2006
Location: Co. Durham, UK.
Posts: 1,117
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Re: Goblin electric clock model 31 Alarm - working of sorts.
Quote:
Can a 'sticky' warning be put on the site somewhere, refuting the falsehoods on that scare-mongering site, before all original synchronous clocks are either destroyed or turned into something else? That fellow's a fanatic, and people need to be warned. |
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17th Mar 2022, 10:40 pm | #17 | ||
Pentode
Join Date: Jul 2020
Location: Falkirk, Stirlingshire, UK.
Posts: 200
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Re: Goblin electric clock model 31 Alarm - working of sorts.
Quote:
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21st Mar 2022, 2:42 pm | #18 |
Octode
Join Date: Mar 2006
Location: Co. Durham, UK.
Posts: 1,117
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Re: Goblin electric clock model 31 Alarm - working of sorts.
The request was made as a response to the wholesale condemnation of historic synchronous clocks IN GENERAL, and not to any specific example listed here.
The fellow starts his rant with: "Making Old Synchronous Clocks Safe to Use" As if they are somehow intrinsically NOT. This isn't, in my view, an opinion which should go unchallenged. |
21st Mar 2022, 7:45 pm | #19 |
Moderator
Join Date: Jan 2003
Location: Ipswich, Suffolk, IP4, UK.
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Re: Goblin electric clock model 31 Alarm - working of sorts.
You've both made your points for members to read and consider.
Thread closed. The OP can ask for it to be reopened if he needs further help.
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Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |