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Vintage Test Gear and Workshop Equipment For discussions about vintage test gear and workshop equipment such as coil winders. |
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19th Sep 2020, 6:23 pm | #1 |
Heptode
Join Date: Jan 2016
Location: Wolverhampton, West Midlands, UK.
Posts: 777
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Hunts CRB: how practical for modern use?
Hi, Re my ongoing collection of vintage test gear, I have come across the famous Hunts CRB. Would a working example be worth restoring so as to use it in active service, or will I be better off using one for shelf dressing and buying something modern? I know which i would like but I guess I want to know if a restoration would have any major sticking points, such as "unobtainium" components or the device just being too darn worn out to work?
Cheers from Bill. |
20th Sep 2020, 1:21 pm | #2 |
Octode
Join Date: Dec 2010
Location: St Ives, Cambridgeshire, UK.
Posts: 1,180
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Re: Hunts CRB: how practical for modern use
Hi Bill,
Which Hunts CRB do you have? There were three versions. Andrew
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20th Sep 2020, 2:32 pm | #3 |
Dekatron
Join Date: Jun 2016
Location: London, UK.
Posts: 3,687
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Re: Hunts CRB: how practical for modern use
I'm not sure it has any practical use compared to a lot of modern kit. For example I have a nice Peak LCR45 that does most of the required functions. If I want to measure leakage of a capacitor I tend to stack some bench power supplies up to the desired voltage (I can hit 200v with three of mine) and use a Fluke DMM in series.
Shelf dressing definitely worth it! |
20th Sep 2020, 2:41 pm | #4 |
Dekatron
Join Date: Nov 2003
Location: Heckmondwike, West Yorkshire, UK.
Posts: 9,643
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Re: Hunts CRB: how practical for modern use
I've got one of the early metal ones. Seems reasonably accurate, but the eye is very dim making it awkward to use. Unless you're keen on end - end authenticity, like much equipment it's of its time.
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20th Sep 2020, 5:21 pm | #5 |
Heptode
Join Date: Jan 2016
Location: Wolverhampton, West Midlands, UK.
Posts: 777
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Re: Hunts CRB: how practical for modern use
Many thanks guys. I have been shown a picture of an original version, local to me (we head into a new lockdown here on Tuesday). The guy plugged it in to show the magic eye in action. This worries me in case things start to sizzle in there, no Variac or anything used to bring the power up slowly. It's owned by a contact who is a dealer in decorative antiques, he has no experience of vintage electronics.
Well guys, worth a punt if under £50, or leave well alone? Cheers from Bill. |
20th Sep 2020, 10:08 pm | #6 | |
Octode
Join Date: Jul 2009
Location: Cheshire, UK.
Posts: 1,740
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Re: Hunts CRB: how practical for modern use
Shango066 on youtube sometimes uses a couple of different "eye" based capacitor testers to either spot check capacitors for value & leakage, or to confirm they were the cause of the diagnosed fault.
Quote:
David |
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21st Sep 2020, 9:03 am | #7 |
Dekatron
Join Date: Jun 2016
Location: London, UK.
Posts: 3,687
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Re: Hunts CRB: how practical for modern use
Excellent advice.
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21st Sep 2020, 12:11 pm | #8 |
Octode
Join Date: Nov 2005
Location: Surrey, UK.
Posts: 1,874
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Re: Hunts CRB: how practical for modern use?
The trick is to use the DVM on a voltage range (an autoranging meter is better), in series with the device under test.
So if your DVM has an input resistance of 10 Meg Ohms, and after your capacitor under test has charged (and is leaking) you can easily estimate its leakage resistance by just reading the voltage in relation to the power supply voltage. For example, if you apply 200V to the series combination, and the DVM reads 100V, you have 10 Meg Ohms leakage. Use potential divider arithmetic for other results. Leon. |
21st Sep 2020, 4:53 pm | #9 | |
Octode
Join Date: Dec 2010
Location: St Ives, Cambridgeshire, UK.
Posts: 1,180
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Re: Hunts CRB: how practical for modern use
Quote:
Andrew
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Invisible airwaves crackle with life. Or they should do. BVWS Member |
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21st Sep 2020, 8:09 pm | #10 | |
Octode
Join Date: Jul 2009
Location: Cheshire, UK.
Posts: 1,740
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Re: Hunts CRB: how practical for modern use?
One of those branded Hunts sold a few months ago, I did wonder about the connection with the Solar version I've seen in the US.
Quote:
With more modern LCR meters you have to be careful to discharge capacitors before testing, as they don't usually have any input protection against high voltages. David |
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