Hi Nigel,
No U.S. vacuum cleaners are all 120V, we use 240V power for stoves, hot water heaters, clothes dryers and that is about it. We do have 15A and 20A industrial receptacles available for 240V, but am uncomfortable advocating for their use since there is no neutral on a domestic 240V connection so both sides of the line are hot - a small, but potential safety issue IMHO. Both neutral and ground or ground are available depending on the receptacle used.
I'm much more comfortable with a small step up auto transformer or industrial control transformer into such a network. It goes without saying (I hope) that the primary side of that transformer should be locally fused.
As Nigel has noted an X or Y cap should used.. Note that motor run capacitors with this rating are acceptable as well.
Note that the output connection of this circuit will rise to close to the raw AC when not loaded and could represent a hazard to anything other than an induction motor plugged into it.
The neon lamp in a TD124 may operate down to a mains voltage of around 90V on the 100 - 120V tap depending on the condition of the specific lamp.
No U.S. vacuum cleaners are all 120V, we use 240V power for stoves, hot water heaters, clothes dryers and that is about it. We do have 15A and 20A industrial receptacles available for 240V, but am uncomfortable advocating for their use since there is no neutral on a domestic 240V connection so both sides of the line are hot - a small, but potential safety issue IMHO. Both neutral and ground or ground are available depending on the receptacle used.
I'm much more comfortable with a small step up auto transformer or industrial control transformer into such a network. It goes without saying (I hope) that the primary side of that transformer should be locally fused.
As Nigel has noted an X or Y cap should used.. Note that motor run capacitors with this rating are acceptable as well.
Note that the output connection of this circuit will rise to close to the raw AC when not loaded and could represent a hazard to anything other than an induction motor plugged into it.
The neon lamp in a TD124 may operate down to a mains voltage of around 90V on the 100 - 120V tap depending on the condition of the specific lamp.
I am told the 117-0-117 is left over from the DC days where three wire was used ( + 0 - ). Reading up in the past it was said 117Vrms was the USA standard, 115 also as it works with our 230V standard as a worldwide system. I have 243V right now and 247V last night. UK is a 230V region and 247V is still inside regs. UK was 240V, my house is 1966 and has it's original supply for 240V. We have a 400A ring main on 3 phases using aluminium triangular sections. As there are no industrial users and a minimum 200 kVA it is a very clean supply. The flat top I show is just how the transformer and chain to the power station regulate. Modern useage makes it worse if the capacity is used. In London it can be much worse as digging up the street is not an easy option to do upgrades. UK richest people with best hi fi's often have the worst power. I measured a 100 KVA diesel generator, it was worse. USA I am told is very like ours until final distribution. It is said a 50KVA transformer to a house with ground at the transformer is typical. The problem being neutral shift it is said. We also get neutral shift by a different route of 3 phase which is harder to cure. Some UK houses are supplied Delta to a transformer similar to the USA system without the centre 0V. Lucky if so, farms and remote houses often. These also 50 KVA or larger ( was 25 KVA in the past ). Minimum sized substations in the UK now are 1000KVA unless not economical. One can view a pole transformer as a substation.
I designed the filter to be as simple as possible. I prefer class X2 caps as they meet any UL or similar regulation. Panasonic comes to mind as low cost and good quality. I have used the 275VAC ones in tube amps as they often they have a 630VDC rating if given. The qualities for reliable mains use give good general performance. I suspect Audio types are very similar.
I am not sure if the output inductance of a transformer would change results if doing that. Make it 250VA I would say. That's why I favoured using the 234V supply. If a European RCD was used safety is restored. Looking at Newark Farnell USA what we have is better priced. Buy a back box to make life easy if using a UK type. In much of Europe RCD's are the trusted safety principle and Victorian fusing a last resort. Due to my work ours gets tripped once a week on average.
13Amp Fused RCD Spur Unit 13A 30mA Trip Switch Protection Unit Screwless | eBay
https://www.amazon.com/Silverline-L...=UTF8&qid=1482223597&sr=8-1&keywords=230v+rcd
I designed the filter to be as simple as possible. I prefer class X2 caps as they meet any UL or similar regulation. Panasonic comes to mind as low cost and good quality. I have used the 275VAC ones in tube amps as they often they have a 630VDC rating if given. The qualities for reliable mains use give good general performance. I suspect Audio types are very similar.
I am not sure if the output inductance of a transformer would change results if doing that. Make it 250VA I would say. That's why I favoured using the 234V supply. If a European RCD was used safety is restored. Looking at Newark Farnell USA what we have is better priced. Buy a back box to make life easy if using a UK type. In much of Europe RCD's are the trusted safety principle and Victorian fusing a last resort. Due to my work ours gets tripped once a week on average.
13Amp Fused RCD Spur Unit 13A 30mA Trip Switch Protection Unit Screwless | eBay
https://www.amazon.com/Silverline-L...=UTF8&qid=1482223597&sr=8-1&keywords=230v+rcd
16 RPM
Hello,
Over the last few days I've enjoyed reading the worlds longest Thorens 124 string! I've owned and used my Mk I turntable for going on 40 years now. It is Serial #57393 and I bought it used for $50, including a Rabco SL8E tonearm (which I still have). I own 7 turntables and keep coming back to the 124. Over the years, I've gotten most of the Schopper upgrades (non-magnetic platter, main bearing, motor rebuild) and I've installed the Hanze HiFi motor springs and idler noise reduction kit. It is a really nice and practical turntable to use and usually hasn't been any trouble -- less than most of the others -- although I have had the stepped pulley noise issue over the last year but managed to fix it just before I found your string. (I cleaned lubed the bearing and cleaned and polished the pulley.) I would have saved myself a lot of trouble if I'd found you sooner. My turntable also runs a little fast. I plan to fix that with the Schopper PSU when it becomes available again.
I had the turntable in a Jim Campbell solid plinth for several years, but recently reverted to the open frame Ortofon style I've used most of the time and think I like it better. I use an SME 3009 II (unimproved) tonearm with 3012 counterweights and an EMT XSD 15 cartridge which I really like, although I'm looking for an SME FD200 damper to try with it. I'm attaching a picture of what my turntable looks like now -- hopefully that works.
I do have a small problem I hope you can help me with, however: I can't engage 16 rpm. Is there an adjustment for that? I've never used it, and probably never will use it, but I'd like it to work.
Best regards and Happy Holidays.
Hello,
Over the last few days I've enjoyed reading the worlds longest Thorens 124 string! I've owned and used my Mk I turntable for going on 40 years now. It is Serial #57393 and I bought it used for $50, including a Rabco SL8E tonearm (which I still have). I own 7 turntables and keep coming back to the 124. Over the years, I've gotten most of the Schopper upgrades (non-magnetic platter, main bearing, motor rebuild) and I've installed the Hanze HiFi motor springs and idler noise reduction kit. It is a really nice and practical turntable to use and usually hasn't been any trouble -- less than most of the others -- although I have had the stepped pulley noise issue over the last year but managed to fix it just before I found your string. (I cleaned lubed the bearing and cleaned and polished the pulley.) I would have saved myself a lot of trouble if I'd found you sooner. My turntable also runs a little fast. I plan to fix that with the Schopper PSU when it becomes available again.
I had the turntable in a Jim Campbell solid plinth for several years, but recently reverted to the open frame Ortofon style I've used most of the time and think I like it better. I use an SME 3009 II (unimproved) tonearm with 3012 counterweights and an EMT XSD 15 cartridge which I really like, although I'm looking for an SME FD200 damper to try with it. I'm attaching a picture of what my turntable looks like now -- hopefully that works.
I do have a small problem I hope you can help me with, however: I can't engage 16 rpm. Is there an adjustment for that? I've never used it, and probably never will use it, but I'd like it to work.
Best regards and Happy Holidays.
Attachments
I've rebuilt a few of these and there is no specific adjustment I can recollect that affects only the 16rpm speed and not the others.
If you have not cleaned and lubricated the speed changing mechanism and cam it is probably overdue at this point, that's where I would start. Look for old gummy lubricant residue and remove it with isopropyl alcohol, follow manual guidelines for lubrication. (Available from Vinyl Engine - The Home of the Turntable)
If you have not cleaned and lubricated the speed changing mechanism and cam it is probably overdue at this point, that's where I would start. Look for old gummy lubricant residue and remove it with isopropyl alcohol, follow manual guidelines for lubrication. (Available from Vinyl Engine - The Home of the Turntable)
Thanks Kevin. I read through the owner's and service manuals (again) and didn't see anything about lubricating the speed selector linkages. Would be it be correct to assume that the same 20w oil used elsewhere on the turntable would be OK for lubricating the linkages? Or should something else be used? I've been pretty good about keeping the various bearings oiled, but don't think I have ever lubricated the linkages.
I use a light teflon based general purpose grease for lubricating linkages and cams. There are a number of other choices in suitable greases, and others may have more specific recommendations. Don't use automotive greases due to potential chemical reactions with the additives.
Bushings should be lubricated with oil, and the 20 sae wt oil recommended elsewhere in the thread is fine in most cases, 30 wt may be better for the stepped pulley and idler based on recent experience.
I'm running 30wt oil in my modified main bearings these days, that's probably not something I would recommend for most tables.
Bushings should be lubricated with oil, and the 20 sae wt oil recommended elsewhere in the thread is fine in most cases, 30 wt may be better for the stepped pulley and idler based on recent experience.
I'm running 30wt oil in my modified main bearings these days, that's probably not something I would recommend for most tables.
Bronze bushings
Good morning,
All the reading that I've done re sintered bronze refers to the "cavities" therein for capturing the lubricating fluid, and the porosity (and capillary action) that allows the lubricant to slowly move into and totally saturate the bushing. Ideally the bushing should be vacuum impregnated with the required lubricant (normally a 20wt -30wt oil) for a given minimum time related to the wall thickness and total volume. Of course diy-ers don't necessarily have access to such equipment, so the age old time, temperature (low) and patience are the means we resort to more often than not.
Kevin
Good morning,
All the reading that I've done re sintered bronze refers to the "cavities" therein for capturing the lubricating fluid, and the porosity (and capillary action) that allows the lubricant to slowly move into and totally saturate the bushing. Ideally the bushing should be vacuum impregnated with the required lubricant (normally a 20wt -30wt oil) for a given minimum time related to the wall thickness and total volume. Of course diy-ers don't necessarily have access to such equipment, so the age old time, temperature (low) and patience are the means we resort to more often than not.
Kevin
The main reason the bearings were like this was to allow for loss of oil ( sometimes for years ! ). The oils of the day were perfect for them. If using a modern oil I would consider a change to a special engineering plastic for the bearing shells. If so a 100% sealed bering is required. The fitted bearings can react to modern oils. These are designed for high preasure as in a pumped system. ATF is OK.