Technics 1210 internal regulation mods

[Mike_New]

Hi UV101,

Where have you placed the two 10.000uF caps? as I am surprised you are getting that much volatge drop on startup at the unregulated side.

[UV101]

Hi Mike,

The 2 caps are in the external PSU. I have a 30va 18v TX into the MBR16100's and then the 2 10,000uF TSUPs. This unregulated feed is then fed onto the TT where my regulator is fitted. The dip I'm seeing is on the caps in the PSU. Its only on start up and stop, not during normal running.

Attached a few pics

[leo]

I didn't try an unregged external psu but did compare two regged ones, even with the 1210 internal regulation there was audible differences to my ears between the two external regged psu's. If you can do it easy enough Ian I'd try a regged one too tbh mate.
I don't get any voltage drop at start up

[leo]

Nice job btw

[UV101]

TY

Hamond case came from Farnell but the front and rear panels along with the PCB came from Brent (Fidelity Audio). Makes the job look very tidy!

Its been a while (6 years) since I last had a working TT and even in the unfavourable location, its been a blast getting the old vinyl out and having a listen!

Mike, I've PM'd you about your bearings!!

[UV101]

I didn't try an unregged external psu but did compare two regged ones, even with the 1210 internal regulation there was audible differences to my ears between the two external regged psu's. If you can do it easy enough Ian I'd try a regged one too tbh mate.
I don't get any voltage drop at start up

Cheers Leo, I'll pop a reg in there tomorrow and report back!

[Mike_New]

Hi Mike,
The 2 caps are in the external PSU. I have a 30va 18v TX into the MBR16100's and then the 2 10,000uF TSUPs. This unregulated feed is then fed onto the TT where my regulator is fitted. The dip I'm seeing is on the caps in the PSU. Its only on start up and stop, not during normal running.

Hi Ian,

I am surprised you are seeing such a relatively large voltage drop across 20,000uF
It could be that your DVD is recording just a very short transient drop.
A scope would be the best way to check these things.
Perhaps this is where Paul's special transformer comes into it's own!!
The regulator is doing it's job though!!

[Reid Malenfant]

Hi Mike,
The 2 caps are in the external PSU. I have a 30va 18v TX into the MBR16100's and then the 2 10,000uF TSUPs. This unregulated feed is then fed onto the TT where my regulator is fitted. The dip I'm seeing is on the caps in the PSU. Its only on start up and stop, not during normal running.

Hi Ian,

I am surprised you are seeing such a relatively large voltage drop across 20,000uF

Has anyone here discovered the VA rating of the transformer?

Just a thought

[UV101]

Perhaps this is where Paul's special transformer comes into it's own!!

Now you got my attention! (well apart from the fact that its 00:15 here and I've got to be up for work in 5 hrs!

Is the TX "special" or is it just more VA? Leo?

Indeed the DVM shows a dip momentarily which of course could be misleading. I'm going to pop another reg in the external PSU case tomorrow and I'll set it about 25v (I should have the head room) I'll take a look with the scope while I've got it in bits again......

[MartinT]

Now you got my attention! (well apart from the fact that its 00:15 here and I've got to be up for work in 5 hrs!

Is the TX "special" or is it just more VA?

Hi Ian, Paul describes the transformer here. Lots more good info in this thread, too:

http://theartofsound.net/forum/showt...?t=6819&page=8