Timestep power supply

[Simon_Nottingham]

Hi. I've just bought a Timestep HE power supply from here for my 1210. It didn't come with the original lead, just a Mark Grant cable with + and - at one end and + - and ground at the other.

The psu has a 4 pin locking connector. It looks to me to be the same as a CB radio mic connector - if so, that's easily sourced from eBay.

I have instructions for fitting the turntable end, but I'm not sure which wires go to which pins at the psu end.

Any help gratefully received.

Thanks.

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[Simon_Nottingham]

Has anyone got any advice?

I've taken the back off the Timestep and I know where to wire the + & - (only two pins are connected- red & black) but does the ground connect to the psu end or the technics end?

Anyone?

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[CageyH]

I would say that the ground went at the Technics end as it serves no purpose at the PSU end (as the pins are not connected in the PSU) but I would contact the guy you bought it off for confirmation as to where it goes, and what it does.

[Simon_Nottingham]

Will do. But if it's not connected at the psu end what purpose would it serve ?

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[Cycleallday]

The main thing you need to avoid is an earth loop caused by connecting different items in your system to different earths. It is not uncommon for a modern PSU to not have an earth connected to its mains plug if it is insulated. If the Mark Grant cable has 3 wires just remember it is not the dedicated lead and may have a cable which is not required. If you have taken the top off the psu you should be able to see if the mark grant earth lead, or the psu output (DC) socket earth pin is connected to the PSU case. If not then there is no point in connecting the lead to any other device at present.

You should have an earth lead from your Technics connected to your phono and then possibly to your amp. Ignore the output (DC) psu cable earth for now and report back if you here any buzzing. Don't worry the psu will be earthed via its input lead if it is necessary so you will have no risk of mains shock.

Mel

[Simon_Nottingham]

Thanks. That's really useful.

The instructions I've seen are just mentioning ÷ive & -ive connections, but then there was a rather fractious debate from here about ground leads. I'll give it a go and see where I get to.

Cheers

Simon

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[Dubster68]

Thanks. That's really useful.

The instructions I've seen are just mentioning ÷ive & -ive connections, but then there was a rather fractious debate from here about ground leads. I'll give it a go and see where I get to.

Cheers

Simon

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Simon

If you can wait until tomorrow I will open mine up and take a few pics if that helps you.

[Simon_Nottingham]

Perfect. Thanks

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[Simon_Nottingham]

I can see that the lead on the right (as you look from the back) is black and the right is red. The top and bottom pins aren't connected. So I'm assuming connect to those two and ignore the ground. As the Technics deck only has a two pin mains lead and the power supply is 21v there should be no issues.

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[Cycleallday]

Thats correct - sounds like no earth issues for the power supply. Have you tried contacting Dave Cawley at Timepstep/Sound Hifi for instructions - contact details below?

There were several versions of this power supply and a couple of connection options depending on what switching controls you want to retain. I also think at least one (if not all) bypass the Technics regulator so you may need to be looking beyond just connecting the psu output lead to the obvious Technics dc input points (that is the input points the Technics psu use)

Sound Hi Fi
PO Box 2001 Dartmouth Devon TQ6 9QN Great Britain
Telephone 01803 833366 Fax 01803 839498 e-mail sales@SoundHiFi.com

[Simon_Nottingham]

Thats correct - sounds like no earth issues for the power supply.

I've been having a dig round on some old posts here and I found the following post by Mark Grant referring to the DSP 1.0 cable that I have:

"2 x 1.0 mm twisted cores and lots of screening (the screen would need to be earthed at the PSU end in the XLR etc)"

So I think I've sorted that one!

[Simon_Nottingham]

Have you tried contacting Dave Cawley at Timepstep/Sound Hifi for instructions - contact details below?

I did email Timestep directly, but didn't receive a reply. I've emailed Sound HiFi. Thanks.

[Simon_Nottingham]

I did email Timestep directly, but didn't receive a reply. I've emailed Sound HiFi. Thanks.

Dave has replied and will post instructions to me. Great service.

[Dubster68]

Simon,Here you go I don't know if they will help.

http://i24.photobucket.com/albums/c25/Mick1B/IMG_5035.jpg (http://s24.photobucket.com/user/Mick1B/media/IMG_5035.jpg.html)

http://i24.photobucket.com/albums/c25/Mick1B/IMG_5036.jpg (http://s24.photobucket.com/user/Mick1B/media/IMG_5036.jpg.html)

http://i24.photobucket.com/albums/c25/Mick1B/IMG_5038.jpg (http://s24.photobucket.com/user/Mick1B/media/IMG_5038.jpg.html)

http://i24.photobucket.com/albums/c25/Mick1B/IMG_5040.jpg (http://s24.photobucket.com/user/Mick1B/media/IMG_5040.jpg.html)

http://i24.photobucket.com/albums/c25/Mick1B/IMG_5037.jpg (http://s24.photobucket.com/user/Mick1B/media/IMG_5037.jpg.html)

http://i24.photobucket.com/albums/c25/Mick1B/IMG_5039.jpg (http://s24.photobucket.com/user/Mick1B/media/IMG_5039.jpg.html)

http://i24.photobucket.com/albums/c25/Mick1B/IMG_5041.jpg (http://s24.photobucket.com/user/Mick1B/media/IMG_5041.jpg.html)

[Simon_Nottingham]

Super! Thanks, really useful.

I think with this, a few posts here and (most usefully) Dave Cawley very helpfully posing me a set of instructions, I'll get it sorted now.

Cheers!

[Mike_New]

Hi Simon,
It's Sunday morning here and I've just dialed in to see what the activity is these days.
If you have (or are getting) the instructions from DC; Unless he has modified them, they will instruct you to connect the 0V (black wire) to the top RH screwed
support of the PCB.
This location on the PCB does not have any direct connection to the 0-Volt via the copper tracks. And is incorrect!
At this point It's only path for the return current is down through the chassis via the self tap screw to the bottom LH screw which DOES have a direct copper connection to the PCB common 0-volt rail. Where the full wave rectifier and primary smoothing capacitor are located.
This situation was high-lighted some 3-4 years ago by myself and verified and expanded on by Martin Taylor and others.
Your SL1200 will still work but the DC supply to the PCB components will have less than an ideal electrical path/circuit

[Simon_Nottingham]

Hi Mike.

The instructions did indeed say to connect to the top right screw. I did this and the turntable did not work (i.e. the power switch did not light up (I wired the power switch into the circuit) and pressing the Start/Stop button did nothing). Following various old discussions on here I waded through I connected it to the bottom left and all works fine.

[Dubster68]

Glad you got there in the end Simon. I followed advice on here and connected the earth to the bottom left hand corner and never had any issues:D

[Mike_New]

It is really very sad that someone who claims to supply upgrades to the audio fraternity cannot accept that he has made a mistake and do the right thing by his customers. And whose ego will not allow him to correct it. Even after over 5 years of people commenting on the situation, the instruction manual is still not corrected according to Simon.
It is not as though the error in placement of the earth point is to do with signal level currents only. Here we are talking about the return path for the total current drawn by the whole of the PCB control unit and motor coils.