Hi! First post here, I’ve read about the forums but haven’t seen anything on this so thought I’d ask people who may know…
I have an old Linn LP12 (fairly sure it’s a 1973) with the old pre-basik choc-block power arrangement consisting of simply 2 capacitors.
Recently the motor lost power (ran at half speed and even jumped into reverse a couple of times) so I replaced it to a slightly newer one, but still have problems.
I’m now thinking I’ll replace the 2 capacitors as it may be they’ve just had enough after 50 years of service. From what I can determine, one is a large grey Plessey 0.22uF 300VAC/600VDC, and the other is a mustard 0.22uF 400VDC.
I know enough electronics to swap things about and not kill myself in the process, but not enough to know if there’s a reason I can’t just replace these with 2 identical polypropylene metal film caps (0.22uF, 630v seem easily available).
I can’t manage to source a 400v 0.22uF mustard anywhere in the UK yet. I can see 160v but that’s the best I’ve found.
Any advice would be appreciated. I have thought of a Hercules upgrade but funds aren’t there at the moment and I don’t really want to buy a Valhalla knowing it’s only a stop-gap.
I have an old Linn LP12 (fairly sure it’s a 1973) with the old pre-basik choc-block power arrangement consisting of simply 2 capacitors.
Recently the motor lost power (ran at half speed and even jumped into reverse a couple of times) so I replaced it to a slightly newer one, but still have problems.
I’m now thinking I’ll replace the 2 capacitors as it may be they’ve just had enough after 50 years of service. From what I can determine, one is a large grey Plessey 0.22uF 300VAC/600VDC, and the other is a mustard 0.22uF 400VDC.
I know enough electronics to swap things about and not kill myself in the process, but not enough to know if there’s a reason I can’t just replace these with 2 identical polypropylene metal film caps (0.22uF, 630v seem easily available).
I can’t manage to source a 400v 0.22uF mustard anywhere in the UK yet. I can see 160v but that’s the best I’ve found.
Any advice would be appreciated. I have thought of a Hercules upgrade but funds aren’t there at the moment and I don’t really want to buy a Valhalla knowing it’s only a stop-gap.
Can you be a bit more specific? As far as I remember, the LP12 used a 110V motor. The little power supply should therefore provide a voltage reduction and the further necessary phase shift for the two-phase motor. If the motor has lost power or occasionally changes direction one of its phases is either broken internally or the phase shifting capacitor. One cap provides the voltage reduction (isn't there a resistor in parallel?) and the other one the phase shift.
Of course you can change it to something modern, but the input cap should be of a X2 type for safety reasons, I guess. But 160V is definitely not enough.
Why not do something more and change the power supply to a Naim Armageddon?
https://www.diyaudio.com/community/threads/power-for-an-lp-12.245474/
Of course you can change it to something modern, but the input cap should be of a X2 type for safety reasons, I guess. But 160V is definitely not enough.
Why not do something more and change the power supply to a Naim Armageddon?
https://www.diyaudio.com/community/threads/power-for-an-lp-12.245474/
Thanks for the reply and the links! The Armageddon looks interesting - I hadn't seen that one, I'd been considering Hercules and the Origin Live kit to gain the speed selector but I'll keep reading 🙂
At this stage though I would just like to get it back on its feet and running. So I can identify if the motor actually needed replaced or if I can return the motor I purchased and then use the money towards a better PSU in the near future.
As I'm on my 2nd motor with similar results, that would indicate the phase-shift capacitor is most likely the issue. That would be the mustard cap running between the red and blue motor leads wouldn't it? If so, can it be replaced with a simple cap like this? https://www.ebay.co.uk/itm/191012201833 or do I really need to find NOS of the original cap?
The supply is as simple as in the photo - the 2 brown leads you can see going in are the 240v AC mains supply. There are only 2 capacitors - no resistors in this circuit. I know, I've seen early circuit diagrams showing a resistor but mine hasn't got one and in my research I've yet to see a photo of the connector block WITH a resistor. I know the history of the deck and know it wouldn't have been rewired (it was my Fathers, bought from new in '73 and I inherited it a few years back). Perhaps the UK spec. PSU didn't require a resistor and the 2 caps are enough?
Yes, you are probably right. Usually the first and bigger capacitor is in line with the mains. It feeds the red wire and the blue wire is fed by another cap from there. I think that the mentioned capacitors are perfect for the job - but I would never buy them at ebay, since most of the parts sold there are probably fakes. Please use a dedicated supplier like Farnell or Mouser. Did you buy an original motor from Linn as a spare?
The trick of the Armageddon is not only the heavy filtering provided by the oversized transformer, but also the reduction of the voltage as low as possible. So most Armageddon clones do not only use 110V but also another resistor to lower the voltage to around 85V. This provides as much drive as needed, but no more than that.
(But I must admit that I do not use an Armageddon clone anymore, since a friend has sold to me a newer Lingo.)
The trick of the Armageddon is not only the heavy filtering provided by the oversized transformer, but also the reduction of the voltage as low as possible. So most Armageddon clones do not only use 110V but also another resistor to lower the voltage to around 85V. This provides as much drive as needed, but no more than that.
(But I must admit that I do not use an Armageddon clone anymore, since a friend has sold to me a newer Lingo.)
add.
You obviously do not have to buy the "original" capacitor for the phase shift cap, anything with right values will do. I would - as we Audiophiles often do - use at least a high quality cap like a Wima MKS or even MKP. This cap does not have to be 275V or more, but I would use the limit nevertheless.
You obviously do not have to buy the "original" capacitor for the phase shift cap, anything with right values will do. I would - as we Audiophiles often do - use at least a high quality cap like a Wima MKS or even MKP. This cap does not have to be 275V or more, but I would use the limit nevertheless.
I got a spare from lp12bits - it's pre-owned but was tested and should be fine - this was quite an unexpected expense at the wrong time of year. It stopped working on Christmas Day which is not the time to be planning £400+ upgrades 😀
I did look at Mouser but they seemed to want a crazy amount of money for postage... Similarly Farnell aren't really geared up to sending a couple of caps out. Also Hificollective, but I asked them to point to what would be suitable and got nothing back. I even tried my local electronics store but they had nothing. I know what you mean on eBay though, certainly is buyer beware. As that seller has 99.9% positive, all electronics and over 30,000 transactions I'm hoping he's ok...
This will only be temporary - hopefully it'll show me the original motor is still ok. If that's the case then I see Stamford are doing the Hercules for about 258 delivered and maybe it would be a good upgrade - I'm determined anything I upgrade to has to at least give me 45 capabilities. Tired of running home with a nice new bit of vinyl only to find they decided to press it as 2 x 45s. As a part-time musician I appreciate good quality audio but could never afford to be an Audiophile - My setup is KEF Q5's, an Arcam Alpha 7 and the LP12 and that's almost good enough for me 🙂
I did look at Mouser but they seemed to want a crazy amount of money for postage... Similarly Farnell aren't really geared up to sending a couple of caps out. Also Hificollective, but I asked them to point to what would be suitable and got nothing back. I even tried my local electronics store but they had nothing. I know what you mean on eBay though, certainly is buyer beware. As that seller has 99.9% positive, all electronics and over 30,000 transactions I'm hoping he's ok...
This will only be temporary - hopefully it'll show me the original motor is still ok. If that's the case then I see Stamford are doing the Hercules for about 258 delivered and maybe it would be a good upgrade - I'm determined anything I upgrade to has to at least give me 45 capabilities. Tired of running home with a nice new bit of vinyl only to find they decided to press it as 2 x 45s. As a part-time musician I appreciate good quality audio but could never afford to be an Audiophile - My setup is KEF Q5's, an Arcam Alpha 7 and the LP12 and that's almost good enough for me 🙂
I have no experience with the Hercules, but it seems to be very similar to the Valhalla, but with the 33/45 option. Go for it, if you have the spare money. The Armageddon will be pricey (if you do not have the parts already) by itself without that option.
Anyway, good luck with the repairs. You can always check the motor windings with a simple Multi-Meter, something you should have anyway.
Anyway, good luck with the repairs. You can always check the motor windings with a simple Multi-Meter, something you should have anyway.
I appreciate the help, hopefully some parts will show up on Monday and I’ll get it spinning again.
Probably old news for people here, but I found a ‘Revolution’ power supply from these guys here https://www.missinglinkcables.co.uk/linn-lp-12-upgrades that may also be worth adding to my shortlist.
Probably old news for people here, but I found a ‘Revolution’ power supply from these guys here https://www.missinglinkcables.co.uk/linn-lp-12-upgrades that may also be worth adding to my shortlist.
You can find for nothing a bunch of X2 capacitors in some out of order PSU for desktop computers. I guess you'll find the good value easily.
Just as a follow-up, it was indeed the mustard capacitor. Replaced with the thin-film cap that arrived today. Fixed the problem so I reverted to my original motor and am currently listening to my first vinyl in a couple of weeks after having set the speed up and replaced the belt.
Lp12bits have been great, they will take back the unnecessary replacement motor so I’m going to start working out the funding on a new PSU. Very interested in that Vinyl Revolution one, £100 over a Hercules but maybe worth the extra for what seems to be a better design.
Lp12bits have been great, they will take back the unnecessary replacement motor so I’m going to start working out the funding on a new PSU. Very interested in that Vinyl Revolution one, £100 over a Hercules but maybe worth the extra for what seems to be a better design.