Technics RCA PCB Replacement

[sunspot]

So, a while back I replaced my original 1210 RCA wires, which were bad, and while desoldering the wires from the circuit board I ended up (I guess) overheating and lifting part of the circuit board RCA contact. I also did the ground wire delete mod. In any case I think ever since then the one turntable has been noisier than the other. I'm not sure I've been happy with the ground wire delete...but whatever. The problem I'd like to address is replacing the bad PCB so I bought 1200s.com's RCA Terminal Board (Technics Parts) [RCAPCB] https://1200s.com/Store/product_info.php?products_id=10000149

I need to go from this:
http://img6.imageshack.us/img6/3143/1tonearmorg.jpg
https://1200s.com/Store/images/Parts/PCBRCA.jpg

To this:
https://1200s.com/Store/images/Parts/RCAPCB.jpg

Anyone here done this? At one point I guess there was a how to on 1200s.com but it looks like it's no longer around. As far as I can tell I simply duplicate where the leads go onto the new pcb board stems but I think I also need a jumper in there somewhere.


Btw, VERY interesting tonearm dampening mod found here - http://www.hifivision.com/phono-turntables/23902-success-technics-sl1200mkii-tonearm-rewire-damping.html

[djlotus]

Why didn't you buy a replacement pcb?

You shouldn't need a jumper. From left to right it should go tone arm black and chassis ground - tone arm green and RCA right shield - tone arm red and RCA right positive - tone arm white and left RCA positive - tone arm blue and RCA left shield.

[sunspot]

Why didn't you buy a replacement pcb?

I bought these quite a while back and they didn't have the actual og pcb. Plus this looked a bit more stout compared to the original.

[djlotus]

As long as it fits.

[DTR]

As far as I can tell I simply duplicate where the leads go onto the new pcb board stems but I think I also need a jumper in there somewhere.

The wires that go to the Left and Right "+" terminals on your original PCB need to go to the middle terminals of whichever RCA sockets you're using. The wires on the "-" terminals need to go to the RCA outer ring, and can be bused together. That new one you've posted looks like the screens (ring part of the socket) might already bused together via the mounting plate. Need to check it with a multimeter to make sure though. If you still want the ground mod, this also has to go to the RCA outer ring.

It's a shame you bought a 5 gang RCA when you're only using two sockets. You could always hacksaw it up if you're that way inclined.



Btw, VERY interesting tonearm dampening mod found here - http://www.hifivision.com/phono-turntables/23902-success-technics-sl1200mkii-tonearm-rewire-damping.html

Tinkering with hifi gear is a slippery, slippery slope and the quest for a perfect sound can drive a man mad! But if you've got the time, money and inclination then why not? Just don't forget it's about the music, not the gear ;)

[djlotus]

Shit, that is an RCA stip. LOL. looked like a screw down strip. Don't do what I said in my initial response if that's the case.

Do they expect you to mount that where the old PCB goes?

[sunspot]

That new one you've posted looks like the screens (ring part of the socket) might already bused together via the mounting plate. Need to check it with a multimeter to make sure though. If you still want the ground mod, this also has to go to the RCA outer ring.

It's a shame you bought a 5 gang RCA when you're only using two sockets. You could always hacksaw it up if you're that way inclined.



I'm not sure I follow about the "5 gang RCA when only using two sockets". But No I don't think there's any busing going on here with the mounting plate.

On the RCA terminal board I bought my connections are going to look like...

(metal pegs are the #'s)
1- RCA L Shield & T Arm Blue
2- RCA L+ & T Arm White
3- RCA R+ & T Arm Red
4- RCA R Shield & T Arm Green
5- Ground Chassis & T Arm Black

What am I missing? Are 1 and 4, suppose to go to 5?

[djlotus]

Do RCA cords plug directly into that strip?

[sunspot]

Do RCA cords plug directly into that strip?

no. They're small pegs you solder to.

http://i.imgur.com/bAoMc.jpg
http://i.imgur.com/ZcART.jpg

[djlotus]

The illustration looks correct. Not sure about the jumper though.

[DTR]

I'm not sure I follow about the "5 gang RCA when only using two sockets".

Very sorry, please forget I said anything! From your first post I thought the strip had 5 RCA sockets. I see now that it doesn't. Sorry for any confusion

[DTR]

You can put a jumper between the shields / screens if you wish. I'm sure the original PCB did, but they will be bussed together at the mixer anyway.

[sunspot]

You can put a jumper between the shields / screens if you wish. I'm sure the original PCB did, but they will be bussed together at the mixer anyway.

Hmm, well I guess the only thing left to do is to just do it. :uhoh: Not gonna lie I'm nervous about this one. haha I think while I have it open I should do the led light swaps.

[L2daGee]

That PCB board will work even better than the original one. It's way easier to solder, and works great. I've installed that same board on four Technics, and they work flawlessly.

[sunspot]

That PCB board will work even better than the original one. It's way easier to solder, and works great. I've installed that same board on four Technics, and they work flawlessly.

Cool! So any advice on the connections I need to make? Jumper or no jumper? I'm really tempted to bring back the ground wires if I can find them.

[djlotus]

I would go with the connections we originally discussed. As far as the jumper(s), I have never noticed any jumpers between the tonearm grounds. The ground carries through the RCA to the mixer and grounds through the mixer.

[sunspot]

Yeah I think I'll do that. It makes sense. I think I am gonna order some leds though so I can knock it all out at once.