Technics 1210 internal regulation mods

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Originally Posted by Marco

Hi Mark,

Cool, cheers - I get that :)

Aside from reduced noise in the listening environment, I was wondering how the advantages of hand-winding with transformers would impact on audio performance, and in what way? :cool:

I'm thinking here mainly of output transformers (these presumanbly shouldn't buzz as there is no voltage going through them, no?), rather than mains transformers.

Marco.

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Marco,
In the past era of valve amplifiers, when there was nothing else! the better quality transfomers, both Mains and Output were often sealed and vacuum impregnated with oil or resin. This provides excellent insulation properties against short circuit windings and greatly improves the overall performance.
In fact as I write this I have on my desk a quality 7.5H choke made by Parmeko in the UK (do they still exist??) which is oil filled and sealed in a pressed steel package with ceramic terminal insulators! All this for a common inductance!!

The problem today is that many of the so called high quality Mains and output Tranny’s are not offered in vacuum oil filled versions simply because of the cost. This is why IMO people are having problems with output tranny’s that are burning out due to the higher voltages that are being use on the output valve anodes these days.

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Originally Posted by Paul Hynes

Hi Marco,

Mike,

I believe it can be tricky to switch transformers on consistently without risking core saturation using solid-state AC switches (Inteligent Triacs) due to the fact that the voltage and current waveforms can be out of phase at the moment of energising the primary. Because of this, switching on at the zero voltage point on the mains waveform is not a good thing. It will create interference and cause current surges up to 40 times the steady state condition with core saturation problems. I am not up with current technology in the field of solid-state AC switches, and things may be different now with new knowledge improving control systems, but it is worth checking this out because I believe transformer core saturation is something that should be avoided as it stops the transformer behaving properly.

Ian,

I do sell the transformers separately for £100 plus insured carriage and packing of £15 in the UK.

Regards
Paul

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Hi Paul,
I was was not proposing to use a solid-state AC switch, as the primary switch, rather as the bipass switch across the current suppressor. This was in answer to Ian's suggestion of using a relay across the supressor because he did not like the idea of having a device in series with the primary.

But now you come to mention it, I believe there are now 'soft start switches' which act like the soft start function in AC inverter motor controls.

Ian,
I believe you would be better off buying one of Pauls super duper transformers. I may be tempted myself!!

believe me I'm tempted!!!

Having just shelled out for the TT and then immediately spent another £300 ish on the cartridge, stabiliser so I could "nude" it, mat, shell and PSU parts (so far!), I'm trying to work out where would be best to spend next!

I'm in total agreement with the points made by Paul, and of course I fully agree with the theory regarding transformer performance, however, I think for me personally at the moment the £ could be spent elsewhere with bigger gains.

Its definately on the list of will do's

If money were no object, I'd be ordering platter, bearings, PSU etc today! :lolsign:

Hi Mike,

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Marco,
In the past era of valve amplifiers, when there was nothing else! the better quality transfomers, both Mains and Output were often sealed and vacuum impregnated with oil or resin. This provides excellent insulation properties against short circuit windings and greatly improves the overall performance.
In fact as I write this I have on my desk a quality 7.5H choke made by Parmeko in the UK (do they still exist??) which is oil filled and sealed in a pressed steel package with ceramic terminal insulators! All this for a common inductance!!

The problem today is that many of the so called high quality Mains and output Tranny’s are not offered in vacuum oil filled versions simply because of the cost. This is why IMO people are having problems with output tranny’s that are burning out due to the higher voltages that are being use on the output valve anodes these days.

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Thanks for that - most interesting....

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the better quality transfomers, both Mains and Output were often sealed and vacuum impregnated with oil or resin...

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I believe that the output transformers on my valve amp are finished in that way :)

Sadly, quality is lacking in so many areas of audio equipment these days (compared to how things used to be), not just with transformers...

Marco.

Paul, another question. I've been reading through the SR5 thread (awesome! I really like the idea of the downward fireing LED!) and seen the pictures of the internals. Whats the capacitance of the smoothers? They look like the larger FC's near the rectifiers. I had always been lead to believe that larger smoothers were a good thing which is why I got 2 x 10,000uF in my supply (although clearly in underestimated the TX requirements! :doh::lolsign:) Thanks:cool:

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Originally Posted by leo

Paul Hynes designs the best regulation I've come across so was pleased to find he can supply the PR3 modules without the rectifier , this makes them about half size of the full AC input module and makes them a good fit inside the Technics.
The PR3DC-21 DC input modules are suited for the standard 1200/1210 platter , the PR3DCHD-21 are higher current and suited for both standard platter and Mike New platter.

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Does anyone know if you can use Paul Hynes regulators that are mentioned above (or those used in the PS5) in conjunction with a Timestep PSU for an improvement over the stock Timestep?

Any regulator needs input voltage headroom to provide a given stable output, so the answer to that question is 'no', unless the Timestep PSU's output voltage can be adjusted upwards. Paul Hynes will no doubt specify the exact amount of that voltage headroom requirement.

Hi Mike,

Shuggie is correct about the regulator dropout voltage. The DC input version of the PR3 has a dropout voltage of around 5 volts.

The standard Timestep power supply uses a mains transformer with 2 x 9 vac secondaries in series to give 18 vdc which, when rectified would give just over 25 vdc. The regulation factor of the mains transformer would add to this but to allow for the charging ripple waveform super-imposed on the main energy storage capacitor steady state dc voltage, and the fact that the mains voltage can vary, often falling during heavy loading during peak times of the day, The PR3 cannot just be substituted for the LM317 used in the Timestep supply. The Transformer would have to be changed for one with 12 vac secondaries, with preferably a higher VA rating, subject to space limitations within the case.

The other factor to consider is that the PR3DC module would not fit in the Timestep case without removing the Timestep PCB, which has the rectification and energy storage on board. In these circumstances you would need the AC input version of the PR3, which will not fit into the Timestep case anyway. You would be better off getting a higher quality transformer and using a PR3AC input module built into another, larger case, to give you a good upgrade in sound quality.

Regards
Paul

I might also add that those users of the KAB PS should be OK as this unit outputs over 30 volts, which is designed to be inserted across the input rectifier. Although in my judgement this is not the ideal location to connect the voltage (it should be after the rectifier bridge) The output of 30V or more should provide a 'stiff' enough source for the majority of regulator modules.

Hi Folks,

Well I finally found some time to finish fitting the internal regulator modules for the SL1200/SL1210 motor board. It was worth the effort but I am not going to say what the results are as MartinT will be fitting the regulators to his deck in the near future and I feel that it would be better to leave Martin to describe the resulting changes this upgrade makes to the musical presentation especially as, currently, his deck has the Mike New upgrades and the a much better Arm and cartridge than me.

Martin has kindly agreed to describe the upgrade from the point of view of a DIY enthusiast and post pictures of his progress. No doubt there will be a few PMs between us while the upgrade information is transferred. At the end of this we will hopefully have a well-documented path for DIY enthusiasts to follow.

For those who are interested in the internal regulator upgrades I have posted a photo on Photobucket and the link is :-

http://i700.photobucket.com/albums/w.../SR1MS3034.jpg

Regards
Paul