Technics 1210 internal regulation mods

[Paul Hynes]

This has been a while coming but I wanted to be sure the instructions were clear and accurate before posting the upgrade information.

I have revised the upgrade application instructions after feedback from Martin T and Anthony TD who have both applied the upgrade to SL1210 decks. Thanks for the feedback and suggestions. I have upgraded another SL1210 this last week, using these instructions, to verify that they are correct. If you decide to apply this upgrade yourself it is your responsibility to follow the instructions carefully. If you have any questions that need clarification, ask for this on this forum thread, so the information may benefit others. If you doubt your ability to apply this upgrade correctly, and safely, find a technically capable person to do it for you. I am looking into the possibility of appointing technically competent agents in key areas of this country, and overseas to provide a fitting service for those who require it.

PHTAP3
Paul Hynes Technics SL1200/SL1210 Application Note 3 (PHTAP3).
Modification of internal power supply regulation.

Modification procedure.

TAP3.1 to TAP3.11 are photographs showing the modification procedure.

http://i700.photobucket.com/albums/w...ynes/TAP31.jpg
http://i700.photobucket.com/albums/w...ynes/TAP32.jpg
http://i700.photobucket.com/albums/w...ynes/TAP33.jpg
http://i700.photobucket.com/albums/w...ynes/TAP34.jpg
http://i700.photobucket.com/albums/w...ynes/TAP35.jpg
http://i700.photobucket.com/albums/w...ynes/TAP36.jpg
http://i700.photobucket.com/albums/w...ynes/TAP37.jpg
http://i700.photobucket.com/albums/w...ynes/TAP38.jpg
http://i700.photobucket.com/albums/w...ynes/TAP39.jpg
http://i700.photobucket.com/albums/w...nes/TAP310.jpg
http://i700.photobucket.com/albums/w...nes/TAP311.jpg

Remove the Technics mains transformer and power supply board. (TAP3.1) These are now redundant.
Remove the Motor board. (TAP3.1)
Install TDR21 dual regulator board using the transformer mounting screws. (TAP3.2)

Remove the motor board
Remove the following components from the motor board :-

Resistors
R1 – 5K6
R2 – 6K8
R3 – 2K7
R4 – 470R
R5 – 470R
R304 – 560R

Transistors
Q1 – 2SD1265
Q2 – 2SD637
Q3 – 2SD637

Capacitors
C1 – 1,000uf 50V
C2 – 33uf 25V
C5 – 0.022uf
C6 – 0.022uf

Diodes
D1 – Bridge rectifier
D3 – 5v1 Zener diode
D301 – 5V1 Zener diode

Cut pcb track to separate the motor control electronics from the motor drive electronics. (TAP3.3)

Cut pcb track to pin 9 of IC301 (AN 6682). This disconnects IC301 from the 9v4 supply generated by IC201 (AN 6680). (TAP3.5)

Drill a 1mm hole in the now isolated pad next to pin 9 of IC301. (TAP3.5)

Drill a 1mm hole in the pad between IC301 pin 5 and test point G

Drill a 1mm hole in the pad between the junction of C108, C110 and R7. This pad is also connected to pins 19 and 20 of IC101 (AN6675) via a track on the PCB.

TDR21 terminals 1 to 6 are marked on the TDR21 PCB, Z1705, and S1709v4 pin outs are marked on the boards. TDR21 has two 21v regulators on board. The first 21v regulator nearest the 27v input side feeds the control circuitry 21v rail and the two regulators Z1705 and S1709v4. The second 21v regulator furthest away from the 27v input side feeds the motor drive circuitry.

If using Fine Silver wire or annealed copper wire with Teflon insulation it helps to cut and prepare the leads first. The modification requires 1.3 metres of wire if the external power supply lead is wired into the deck or 1.5 metres of wire if a DC inlet connector is fitted to the inlet flange. Fitting a coloured coded rubber sleeve over each end of the Teflon insulation will help with wire identification during assembly. Use red sleeves for positive and black sleeves for 0v wires.

Prepare 2 x 65mm wires for connecting the Z1705 regulator to the motor board in place of D301 zener diode as shown in (TAP3.10). Fit the wires to the motor board and solder.

Prepare 2 x 75mm wires for connecting the S1709v4 regulator to the motor board as shown in (TAP3.9). Fit the wires to the motor board and solder.

Prepare 1 x 240mm wire for 0v and 1 z 300mm wire for +21v to feed the motor drive circuitry as shown in (TAP3.7). Fit the wires to the motor board and solder.

The motor board can now be replaced in the Deck chassis and the various connectors can be refitted.

Fit 12mm stand-offs to Z1705 and S1709v4 and mount them as shown in (TAP3.10) Solder the wires from the motor board as shown in ((TAP3.10).

21v outputs from the first regulator from terminal 4 on TDR21 regulator module. Prepare 1 x 150mm wire for connection to the jumper wire (Marked J on the motor board next to C3), 1 x 140mm wire for connection to Z1705 and 1 x 190mm wire for connection to S1709v4. Solder these wires to the motor board jumper, Z1705 and S1709v4 as shown in ((TAP3.10). Twist the three wires and fit to terminal 4 on TDR21.

21v outputs from the second regulator from terminals 5 and 6 on TDR21 regulator module. The 240mm and 300mm wires that feed the motor drive section are connected to TDR21 with the 240mm 0v wire to terminal 5 and the 300mm 21v wire to terminal 6.

Connect the external 27v power supply to TDR21 input terminals either directly from the power supply DC lead or via an input connector as shown in ((TAP3.11). The DC input 0v wire should be fitted to terminal 2 and the +27v wire to terminal 1.

Thoroughly check all wiring before refitting the platter and applying power to the external power supply.

[Wakefield Turntables]

OH FCUK! WHAT HAVE I LET MYSELF IN FOR

[RobbieGong]

OH FCUK! WHAT HAVE I LET MYSELF IN FOR

Ha Ha, I was just thinking exactly the same - You guys a far braver men than me

[Paul Hynes]

Andy,

I have already told you that FCUK is not French.

If you do not feel comfortable fitting the internal regulator upgrades send the deck, sans (that’s French for without) the arm, to me. I can do the modifications for you.

PS. I have Made in Japan and will spin it once I have finished my bearing and platter upgrades.

Regards
Paul

[Stratmangler]

I have Made in Japan and will spin it once I have finished my bearing and platter upgrades.

Regards
Paul

The best live rock album ever!
Bar none.

[Wakefield Turntables]

Andy,

I have already told you that FCUK is not French.

If you do not feel comfortable fitting the internal regulator upgrades send the deck, sans (that’s French for without) the arm, to me. I can do the modifications for you.

PS. I have Made in Japan and will spin it once I have finished my bearing and platter upgrades.

Regards
Paul

Paul,

I'm trying to stop swearing hence the usage of fcuk, I suppose I could use fook instead!! I want to learn how to do these regs so i'm going to buy a spare 1210 PCB and if I fook (there you go!!!) it up I have a spare. I also fancy having ago at doing that little project I was telling you about over the phone with the spare PCB Thing is you need to remove so many components that there will be nothing left of the PCB to upgrade which is even better for me. Anyway, all I can say is that your PSU is getting better and thanks for all your hard work.

Andy

[Paul Hynes]

Hi Andy,

If you manage to stop swearing, will you tell me how to do it?

I’m here for any support you need with the internal regulator upgrades.

Regards
Paul

[MartinT]

OH FCUK! WHAT HAVE I LET MYSELF IN FOR

I kinda warned you

[Mike_New]

OH .....! WHAT HAVE I LET MYSELF IN FOR

No Problem Andrew, when you have finished just tune for maximum smoke!!

You will have no problem with Paul he really knows what he is doing and I'm sure he will be able to hold your hand while you quiver and quake with you soldering iron hovering above the PCB.

[Mike_New]

Paul
I have been studying your Instructions with some interest as I will need to modify both my PCB and the one for my Lathe cutting friend. and I have one observation which may help those who are not adept at weilding a soldering iron, especially when trying to remove components.

The Resistors R2 & R4 are the only ones connected to the regulated 21V rail which are directly associated with the regulator circuitry which we are removing.
Now if we cut the copper track just below J3 where the regulator Q3 output is connected. This will isolate R2 & R3 from the new regulated supply from your module. We will also need to remove Q3 but this is relatively easy as it is connected to the main PCB with three wires, these wires can even be cut if required.
This will still leave C3 connected across the new supply. The common 0V tracks are track 1 & 3 as veiwed from the top of the PCB

In this way surely people can now leave in the board, all the 21V regulator components down at the bottom LH corner if they wish and opt to cut another track instead. Your image TAD34 shows a nice clean space and this is the way I would do it.
However the option would remove a lot of heartach for the likes of Andrew and others.

Also a word of caution for those people who have fitted my bearing and who will have removed the plastic cover over the coil assembly.
In order to avoid any damage to the coil assembly when working on the board, refit this cover during the work.
If you do not have the cover then use a soft towel to rest the coil assembly on.