Pink Triangle LPT GTI power supply board

[Geoff101]

Hello,

I've got a Pink Triangle LPT GTI which has a cooked motor control board (a common problem it seems).
It's badly discoloured, has lifting tracks and loose compoents.
I could patch it back together and get it working but it would still look a whisker away from burning my house down.

Are there any viable options for replacing it? I'm aware that Funk Firm do a DC upgrade but the price is ridiculous.
Other than that, it's in very good nick so seems a shame not to get it working.

Thanks

[Mr Kipling]

Any chance of a photo?

[Geoff101]

Sure - here you go:

http://www.g32.co.uk/images/LPT_1.JPG

http://www.g32.co.uk/images/LPT_2.JPG

http://www.g32.co.uk/images/LPT_3.JPG

[Firebottle]

The resistors don't look discoloured so is it all the small signal transistors that are getting hot? Try the end of your little finger on the top of them to see which ones are getting hot.

I would add little clip on heat sinks to dissipate the heat.

:cool: Alan

[Mr Kipling]

A bit more complex than I imagined. And looking on the web found that, as you say, it's a common problem. The board getting discoloured with it being powered up all the time and not being switched off at the mains.

If you don't want to spend money I'd replace the capacitors and any resistors that look stressed and repair the tracks were I could and fit a switch at the back to kill the mains or fit and in-line lamp-type on/off switch.

If you want something you can forget about and not have to worry about, and is not too expensive ( don't know how much the Funk item is), then an Armageddon clone would seem to be the easiest option. I'm assuming the motor is AC. If you Google DIY Armageddon Clone you'll find the PFM thread. It's basically a 500Va 55V + 55V transformer in a box. Here's a photo from the thread:
http://img.tapatalk.com/d/14/10/26/eru2ysy6.jpg
You'll find the transformer on eBbay for £64 - 361053597153.

You'll find a Naim case too. Costs £80 though.

Looking again at the first photo, the motor is AC.

[Geoff101]

Is that a single speed supply? The LPT GTI has a two speed motor.

[The Barbarian]

Geoff your 'LPT' is different to mine, mine had a thick base all textured black finish. It did have the same PSU board as yours though with the acrylic knob that illuminated pink or green which ever speed you selected.

[Mr Kipling]

Yes. It will just give you 33.

Had a look at the Funk Firm's prices. Try Googling "Falcon Power Supply". There's a thread on Steve Hoffman's site. It's £235 + carriage and will give 45rpm.
http://img.tapatalk.com/d/14/10/26/a9a3y7y5.jpg
There's Origin Live. But don't know what their prices are like.

[Geoff101]

Hmm...sounds like it might be a case of keep the arm and sell the rest on for parts.

[loo]

Find out what make and model the motor is then it is a lot easier to determine a solution
its far too good a deck to break up though . Ask Richard (oldpinkman on here) if he can
find out what motor PT used.
cheers
Paul

[The Barbarian]

It's an Airpax{Premotec} its glued into that round pod.

[The Barbarian]

The guy who has my old deck has fitted a DC motor & alser fitted a black cap over the speed control knob cut out

[loo]

It's an Airpax{Premotec} its glued into that round pod.

Do you know what voltage they used Andre

[YNWaN]

I would be very surprised if it isn't the standard 240V version. Therefore any supply designed for the LP12 AC motor will work.

[loo]

I would be very surprised if it isn't the standard 240V version. Therefore any supply designed for the LP12 AC motor will work.

yeah, that was my thinking also some of the pro-ject speed boxes may work

[Oldpinkman]

Find out what make and model the motor is then it is a lot easier to determine a solution
its far too good a deck to break up though . Ask Richard (oldpinkman on here) if he can
find out what motor PT used.
cheers
Paul

Motor is a premotec / airpax as used in the original LP12. Martin Colloms and market pressure made us use it, when we knew the DC motors we originally used were better. No other single subject is more likely to wind AK up. So his only option will be a DC replacement to do the job properly. The VX conversion is accordingly the recommended route. Others (including Origon I believe) do DC conversions too - now everybody has finally accepted what we were telling them when the original PT launched, and Linn and Rega offer DC versions of their products and DC conversions. VX is a dedicated design rather than a universal and benefits from the K-Drive circuit design.

The LPT has the same motor and electronics as the export. GTi versions of both were the same (improved) electronics. It's a good enough deck to justify the DC upgrade, but if you want to just get it back on the road with the existing kit, why not repair the board and relocate it outside the turntable in a well ventilated metal chassis, and switch it off when not in use? Most of the other solutions offered involve an external casing so there should be no issue there.

I know the VX is not cheap, but it is a quality DC replacement drive system for £450, compared with nearly £1200 for the Naim Armageddon which is just a power supply for the AC motor - and not therefore as much of an improvement as a conversion to DC. I quote from the boy himself

Designing circuits for small AC motors is very straightforward.
That must surely be a good thing? Well it is.
There is, however, a flip side: The motors themselves. They Buzz…and there is NOTHING that can be done to get rid of that problem.
That’s a bad thing.

(yes I know - if its that straightforward why has this one burned out? Don't shoot the messenger! :doh:)

[Geoff101]

Thanks for the info. Sadly neither the Origin Live kit or (especially) the Funk Firm VX kit come anywhere close to making economic sense given the value of the deck.

[Mr Kipling]

How can Naim charge that much for a transformer in a box?

[mimoser]

Talk to Edmund Chan - he builds the Hercules board. afaik he will be able to customize his mose/hercules psu for other TTs than an LP12.
Either contact him via ebay (http://www.ebay.com/itm/Mose-Hercules-for-Linn-LP12-acclaimed-External-PSU-replace-Valhalla/251644680143?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%2 6asc%3D26942%26meid%3De08b32683d7e4d8592ab25d47145 cbd6%26pid%3D100005%26prg%3D11184%26rk%3D1%26rkt%3 D6%26sd%3D390914087387&rt=nc) or I could give you his email address via pn.
He is a very nice guy, bought a PSU from him for my former LP12.
;-))
Michael

[Oldpinkman]

It's tricky I appreciate. If its "just an old deck" then you want to keep the repair cost to £50 or so. I think a patch repair to the PCB - rehoused with better ventilation is your only real option. The Hercules may be a fine supply, but its £200 and you still have a buzzing AC motor.

Don't underestimate the turntable though, which punches way above its weight. The world is full of 2nd hand items, but I can't think of a new turntable under £1000 would hold a candle to it. There is more than meets the eye, as AK hints on his web-site, and whilst lacking the Vector drive, its plinth is significantly more sophisticated than it appears. You couldn't build one today to sound like it. So for someone looking for a quality deck its worth the DC upgrade. It will take a good arm - even the new AK47, which is one of the reasons Arthur stuck with rega mounts for Funk arms - the retro fit opportunities on LPT's. Too good for the parts bin!

[Avinunca]

I always suggest people visit the FF/Pink Triangle forum at VinylEngine. There is a wealth of info and many very experienced PT owners.
I was very fortunate in picking up a used vector converted PT1 on t'|Bay and I think the biggest improvement was from the power supply. Hugely expensive for what it is
but I'm sure an equivalent could be constructed for £150. It provided rock solid speed stability with all it's sonic benefits.
My personal experience was that when I moved from my LPT to my first PT1 the sound stage just exploded and I wouldn't personally spend that much on the former. I know that
many rate the LPT very highly but the magic started with the PT1 for me. The vectored conversion is a huge improvement on that.

[smedley]

Hi everyone

I know this has (sort of) been covered above but for a while now I have had to spin my PT LPT-GTi turntable by hand to get it going but thereafter it runs to within its design specification for speed. However, it is definitely getting worse and, I assume, at some point will refuse to run altogether.

I am tempted by a Heed Orbit 2 as it is easy to fit, but can anyone confirm that the Heed PSU would solve the problem and also (hopefully) give an improvement is SQ too?

I don't really have the time, equipment or expertise to look at DC motor replacements like OL, Funk Firm etc..so I would take a lot of persuading that the benefits of DC motors are worthwhile but these and all other options/opinions will be gratefully considered too!

Thanks

Smed