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Vintage Audio (record players, hi-fi etc) Amplifiers, speakers, gramophones and other audio equipment. |
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28th Feb 2021, 11:14 pm | #1 |
Tetrode
Join Date: Nov 2020
Location: London, UK.
Posts: 87
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Electric Gramophones
Hi everyone,
I have some question regards to Electric Gramophones. 1) I wonder which type cartridge they have, what I've seen there is always gramophone needle on them. 2) I presume, if old wander plugs could be replaced with modern RCA, then possible to connect them to modern amplifiers? 3) Some of them have bayonet connectors, can I find any adapter to convert modern plug? Thanks in advance! Fatih |
1st Mar 2021, 8:56 am | #2 |
Dekatron
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 8,302
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Re: Electric Gramophones
I guess what you are refering to is old 78rpm only turntables that use steel replaceable needles. If so, you may find that the old magnetic pick up heads in these will not match a modern amplifier very well.
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Edward. |
1st Mar 2021, 1:52 pm | #3 |
Tetrode
Join Date: Nov 2020
Location: London, UK.
Posts: 87
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Re: Electric Gramophones
Thank you Edward,
I meant that ones yes. Do you think it fits to radios with pickup inputs? Cheers, Fatih |
1st Mar 2021, 2:32 pm | #4 |
Dekatron
Join Date: Sep 2015
Location: Southwold, Suffolk, UK.
Posts: 8,302
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Re: Electric Gramophones
Yes, that was what they were designed for.
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Edward. |
1st Mar 2021, 2:51 pm | #5 |
Dekatron
Join Date: Jan 2005
Location: Oxford, UK.
Posts: 17,820
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Re: Electric Gramophones
They're also often in a bad way, and need re-building, from what I've read (e.g. coil open circuit, and/or rubber bits hard and perished).
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1st Mar 2021, 3:01 pm | #6 |
Dekatron
Join Date: Nov 2009
Location: Lincolnshire, UK.
Posts: 4,990
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Re: Electric Gramophones
I agree. They nearly always need pickup head work and you'll struggle if you don't have the skills to repair them. If the heads aren't right they'll absolutely trash your 78s - they're best avoided in my opinion, unless you're really set on having one and can do the work always needed on the head and possibly the motor, which sometimes has pitch embedded capacitors, with sometimes no marked values on them. I should also mention the different impedance values of the head coils which can be from an ohm or two and needing a matching transformer, up to those with coils of thousands of ohms, then you'll need a good stock of 'play once only' needles to feed it with and some take special needles that you can't get anymore.
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1st Mar 2021, 3:51 pm | #7 |
Dekatron
Join Date: Jan 2012
Location: Brentwood, Essex, UK.
Posts: 5,316
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Re: Electric Gramophones
My 1950's Odhams "Radio Televison and Electrical Repairs" book says that the rubber items in this type of pick-up will probably need replacing. That advice was given more than 60 years ago, so certainly something to be checked. The book mentions three different types: crystal, moving coil, and moving iron. Repair of the first two types was considered to be something best left to the manufacturers, but advice was gven on overhauling the moving iron type, by far the most common type then found. The most important thing was to fit a keeper between the poles of the permanent magnet before dismantling to prevent loss of magnetism.
Last edited by emeritus; 1st Mar 2021 at 4:00 pm. |
1st Mar 2021, 4:17 pm | #8 |
Tetrode
Join Date: Nov 2020
Location: London, UK.
Posts: 87
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Re: Electric Gramophones
Thanks everyone, sounds like I should avoid for now
Cheers, Fatih |
2nd Mar 2021, 10:40 am | #9 |
Pentode
Join Date: Jun 2011
Location: Berkshire, UK.
Posts: 124
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Re: Electric Gramophones
A good place to learn about these pickups is to watch some of Norman Field's videos on YouTube. He revives some and his explanations are very good.
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Richard It's great when it goes around to make a sound. |
2nd Mar 2021, 2:25 pm | #10 |
Dekatron
Join Date: Jan 2012
Location: Brentwood, Essex, UK.
Posts: 5,316
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Re: Electric Gramophones
Here's a scan of the section on pickups from the Odhams book.
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5th Mar 2021, 6:09 pm | #11 |
Tetrode
Join Date: Nov 2020
Location: London, UK.
Posts: 87
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Re: Electric Gramophones
Thank you for your help, definetely I'll read that scan and watch that videos.
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