10 -15 VA torroid and PCB with rectifier , filter and primary regulator then feed that into the main board. Torroids have far lower EMI and the small blue ones would fit into that well with a screw from the bottom to secure it.
The LAB-500 I have received a recap and a lower voltage regulator 18v from 22v.
Any audible hum is from what unit is under the TT rather then the power transformer
the speed switch may get a reed relay or CD4066 upgrade.
The LAB-500 I have received a recap and a lower voltage regulator 18v from 22v.
Any audible hum is from what unit is under the TT rather then the power transformer
the speed switch may get a reed relay or CD4066 upgrade.
True, but don't forget that the original transformer is encapsulated in a mu metal case. This case isolates EMI very, very well.
Be careful not to make it worse.
Very interesting thread.
I have just bought a US 110V SL1210. I live in Sweden, so I need to convert i to 230V. There is no 110/230 switch under the platter.
Will this Mascot switch mode PS work? https://www.mascot.no/media/2071/3626.pdf
I have just bought a US 110V SL1210. I live in Sweden, so I need to convert i to 230V. There is no 110/230 switch under the platter.
Will this Mascot switch mode PS work? https://www.mascot.no/media/2071/3626.pdf
Hi,
from the DS it looks ok, though a bit oversized already .. and its a external supply.
The earlier in this thread mentioned Meanwell supplies are smaller, for internal use and have proven their useability.
jauu
Calvin
from the DS it looks ok, though a bit oversized already .. and its a external supply.
The earlier in this thread mentioned Meanwell supplies are smaller, for internal use and have proven their useability.
jauu
Calvin
So going to an internal SMPS is not as simple as replacing the original? Would I need to rewire stuff?
I want to convert my US SL1200 to 230V. I have read the thread several times now and here I link all important posts for my project. Maybe it will be useful for others too.
Calvin suggests using internal SMPS, Meanwell PM-10-24
Calvin verfies SMPS solution
noviygera reads spec to find EMI filter is built in
noviygera tries the PM-10-24. Low torque. Needs ferrite rings.
AddiDub suggests using RS-15-24
AddiDub supplies schematic
Calvin replies to yakeface. Fuse needs to be smaller
coolmaster points out the switch suppressor capacitor needs replacing
Calvin questions using external smps
- I will be using the Mean Well RS-15-24.
- I will use ferrite rings on primary and secondary sides.
- Fuse will be switched to half the current.
- I will replace the switch suppressor capacitor
Calvin suggests using internal SMPS, Meanwell PM-10-24
Calvin verfies SMPS solution
noviygera reads spec to find EMI filter is built in
noviygera tries the PM-10-24. Low torque. Needs ferrite rings.
AddiDub suggests using RS-15-24
AddiDub supplies schematic
Calvin replies to yakeface. Fuse needs to be smaller
coolmaster points out the switch suppressor capacitor needs replacing
Calvin questions using external smps
Hi, the posts you have linked discuss different matters. First two points are about using a smps instead of a transformer. The second two points are only useful If you replace the Technics transformer with a toroidal transformer.
I removed the original transformer and the psu board. The SMPS output is connected directly to the switch and to the main board where i removed the rectifier.
That means that you end up with an always on SMPS, only the load ist switched. There is also no fuse left in my build and altough it works perfect i dont know how safe it is. That ist why i did not document it further, because i still consider it to be a beta version and not a final approach.
I bet Calvin has a more professionell attempt when he mods Technics players to switching power supplies. Maybe he will share more insights of how to do it right?
I will replace the 125V 250mA fuse with a 250V 125mA medium slow fuse.
The switch suppressor capacitor can be removed right?
Yes, no need to worry about strobe - it should work fine - it's not
a neon bulb connected to the mains unlike, say a Dual 1229
a neon bulb connected to the mains unlike, say a Dual 1229
About five years ago, I externalised the PSU of an SL1700, and while I was at it, the motor control circuitry too.
I thought I might as well externalise the motor too, while I was at it.
To be fair, it was a scrapper, and no viable Technics TTs were hurt in the making of this 😉
I thought I might as well externalise the motor too, while I was at it.
To be fair, it was a scrapper, and no viable Technics TTs were hurt in the making of this 😉
Attachments
I have done rebuilding the power supply with the small MeanWell SMPS. I believe successfully. But.
I have a lot of induced noise from the signal cable. The amout of noice is dependent on how I place the cable. The only "workable" position is over the preamp.
There is still noise when I turn off the player.
My old european (dual voltage) SL-1200 MKII doesn't have this noise at all. Just connect and play.
I have connected protective earth to the SMPS. Maybe this is causing the problems? I cannot figure out why if so.
Edit:
The problem is probably because of the home made cabling lacking screen.
As soon as I get rid of the noise I will post pictures.
I have a lot of induced noise from the signal cable. The amout of noice is dependent on how I place the cable. The only "workable" position is over the preamp.
There is still noise when I turn off the player.
My old european (dual voltage) SL-1200 MKII doesn't have this noise at all. Just connect and play.
I have connected protective earth to the SMPS. Maybe this is causing the problems? I cannot figure out why if so.
Edit:
The problem is probably because of the home made cabling lacking screen.
As soon as I get rid of the noise I will post pictures.
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