Another case of upgradeitis or should I recap my 1210 PCB

[Wakefield Turntables]

GUYS!

Before I embark on another stupid project, is it worth recapping the pcb on my 1210? Some of the caps are nearly 15-20 years old and must have started to become degraded. Your advice and comments would be very very welcome. :cool:

[Mark Grant]

If it's 15-20 years old then why not.:)
Should only cost a small amount for the capacitors.

[Marco]

Good luck with this, Andrew. It's at times like this, though, that I'm glad I bought my Techy brand new :)

That must be a really old deck you've got?

Marco.

[Wakefield Turntables]

I dont know the exact age but its knocking on, some of the caps are bound to be beyond there best. i was thinking of maybe getting a knackered 1210 of ebay and maybe having a play around. I'll keep you all posted if I can find one cheap enough! :cool:

[Mark Grant]

PCB on ebay, not sure if that is the same as in yours though. :)
http://www.ebay.co.uk/itm/TECHNICS-SL-1210-SL1210-1200-MK2-EARLY-SPEC-MAIN-PCB-MOTOR-/230699993751?pt=UK_AudioTVElectronics_HomeAudioHiF i_Turntables&hash=item35b6ca8a97

might be good to have a spare before you start desoldering stuff.

[Wakefield Turntables]

Thanks Mark.

[WOStantonCS100]

If you're experienced with soldering/circuit work, getting components with the right values will be the hardest part of the whole deal. After that it's "pie". You may have to buy some in bulk. If caps have gone out of spec, chances are resistors have as well, especially the carbon comp type, which are known to "drift". The term "cap job" is a little misleading. The overall health of the circuit should be checked, ideally, replacing any out of spec components.

Of course, along with the AOS stated warning for doing electric work, I would say, that inexperience can turn a simple upgrade into a nightmare. Overheating, lifted traces, solder bridges, cold joints, etc. as a result of improper work can turn a functioning (even if in need of attention) turntable into bin filler.

[Wakefield Turntables]

If you're experienced with soldering/circuit work, getting components with the right values will be the hardest part of the whole deal. After that it's "pie". You may have to buy some in bulk. If caps have gone out of spec, chances are resistors have as well, especially the carbon comp type, which are known to "drift". The term "cap job" is a little misleading. The overall health of the circuit should be checked, ideally, replacing any out of spec components.

Of course, along with the AOS stated warning for doing electric work, I would say, that inexperience can turn a simple upgrade into a nightmare. Overheating, lifted traces, solder bridges, cold joints, etc. as a result of improper work can turn a functioning (even if in need of attention) turntable into bin filler.

Good points! I'm reasonable with a soldering iron. To be honest its this winters DIY project, last year it was the Celestion speakers up and running and tweaked. I must admit that i'm not quite a novice when it comes to circuit board work but I think I have enough experience to have a go. I'd probably be replacing the whole PCB components.

[Reid Malenfant]

<snip> I'd probably be replacing the whole PCB components.
:scratch: Why? The integrated circuits should be fine as long as they are fully functional, only capacitors & probably only some resistors will need replacing.

While you are at it fit better components. I'm not famiiliar with the 1210 PCB, but any 5% resistors I'd replaced with 1% metal films which should benefit things. There are no high frequency switching components in there so they'll be ok, pulsing a few electromagnets can hardly be described as difficult or needing non inductive resistors in the circuit ;)

[WOStantonCS100]

Somewhere, someone posted that he replaced his smaller caps with solid caps, the ones that can be readily found on PC motherboards these days. I have no idea what the tolerances are of those. That might be interesting to try since they're not in the "audio signal", per se, where you might want a specific type component for it's particular effect (character) on the sound.

After I get a 78 rpm mod done to one of my boards, I will most likely fully "recap" it.

[Wakefield Turntables]

Mark,

This is why I ask and post silly questions! You guys have far superior knowledge than I when it comes to electronics, and AOS is a very friendly forum so I feel very comfortable looking like a prat and asking silly questions :ner: I'm still learning. OK, so now I have learned to leave the IC's alone. I've just downloaded the 1210 mk2 service manual and all the resistors appear to be 5% tolerance apart from R301 which is 1%. these are all carbon with a few metal film resistors. Looking at the Diodes these is a right old mix of paper, electrolytic or polyster. Which is best? The tolerances again seem high at 10%, is it generally better to get as low a tolerance as possible??

Andy

[Reid Malenfant]

Hi Andy, ok so we got to the nitty gritty :eyebrows:

If there is a 1% tolerance resistor on the board then look for one with 0.1% tolerance ;) They are available trust me. A lot of them will not be that important so while they may be fine with 5% tolerance, 1% will do no harm & you may be replacing some that have "drifted" somewhat from standard. More than likely this would happen if they run quite warm or hot..

You won't find any paper, polyester or electrolytic diodes on the PCB, I think you mean capacitors.

If you can upload the circuit diagram then it's quite possible that we can suggest certain new caps that should improve the performance. Obviously nothing can be suggested if we don't know what each is doing, so circuit diagrams are very helpful :)

[Wakefield Turntables]

Hi Andy, ok so we got to the nitty gritty :eyebrows:



You won't find any paper, polyester or electrolytic diodes on the PCB, I think you mean capacitors.

If you can upload the circuit diagram then it's quite possible that we can suggest certain new caps that should improve the performance. Obviously nothing can be suggested if we don't know what each is doing, so circuit diagrams are very helpful :)

Yes I'm a dumb-ass, I did mean capacitors. OK, am now off to try and find a circuit diagram. Will post when I get one!

[Wakefield Turntables]

Hopefully there should be a jpeg attached of the schematic of 1210 mk2 pcb

[Lodgesound]

Hi Andrew;

If it's working fine then honestly leave it well alone - if it's been used reasonably regularly throughout it's life then there's no reason to suspect that anything needs to be changed.

A quick visual inspection should tell you if there are any leaky capacitors - you will see a tell-tale secretion from any that are.

I have a 28 year old 1210 which has no problems whatsoever and have tape machines and amplifiers that are 30 years old with all original capacitors again with no problems.

I know folk like to say (particularly in the service sector) "oh these will need changing every so and so years...". I've had it said to me in the past by people who make assumptions about my own background before taking the trouble to look a little deeper.

Trust me it's not a car - only go in there and start changing things if they are broken. You are in danger of ending up with more faults than you can fix if you start to interfere.

[Reid Malenfant]

Stewart does have a point ;) It's only amplifiers that tend to give passive components a tough time, due to high current draw but mostly high temperatures.

The Techy will run cool as even with the original transformer in situ, there is nothing there that will get hot under the collar & cook the electrolytics.

By the way Andrew, that's more of a component placement diagram that a circuit diagram from what I can make out :scratch:

[Dingdong]

Vinylengine should have the service manual with the diagrams.

[Wakefield Turntables]

Stewart does have a point ;) It's only amplifiers that tend to give passive components a tough time, due to high current draw but mostly high temperatures.

The Techy will run cool as even with the original transformer in situ, there is nothing there that will get hot under the collar & cook the electrolytics.

By the way Andrew, that's more of a component placement diagram that a circuit diagram from what I can make out :scratch:

Bugger! :scratch:

[Artifolk]

Try here for the service manual.

http://www.eserviceinfo.com/

Just type "sl1210" and download both parts. Rar file