Batery powered DIY CNC phono stage

[sachu888]

Hi Joshua,
Sent you a mail.

Regards,
Sachin

 

[jls001]

Hi Joshua,
Sent you a

Thanks, Sachin. Will make the changes tonight. I am not used to using batteries so I often forget to remove them, and the next time I want to play music batteries are already drained! The on/off switch is a must.

 

[jenson]

Thanks, Sachin. Will make the changes tonight. I am not used to using batteries so I often forget to remove them, and the next time I want to play music batteries are already drained! The on/off switch is a must.

boy, you leave a trail

 

[jls001]

boy, you leave a trail

Life is too short. I'm belatedly learning as much as I can, and hopefully, in the process, improving my audio playback without burning a huge hole in my pocket Also, it's a lot of fun.

 

[omishra]

Life is too short. I'm belatedly learning as much as I can, and hopefully, in the process, improving my audio playback without burning a huge hole in my pocket Also, it's a lot of fun.

That's why my projects are never ending.

 

[jls001]

That's why my projects are never ending.

I have too many on my plate right now so I am not taking up anything more till I finish them off one by one:

1) MyRef - board populated, custom cab purchased, toroidal purchased, connectors purchased - needs integration

2) CNC Phono stage - needs housing, but already being used naked

3) Hypnotoad MC phono stage - needs housing, but already being used naked

4) OPS - populated, not yet tested. Needs housing

5) GRR X-LS Encore - cabinet is being painted and hope to start listening to it soon. And if it sounds half as good as I hope it will, it will need a pair of stout stands. Another DIY project?

6) Lenco L75 Plinth Build - plinth already cut and stacked, motor tested on the plinth, to be glued together and painted.

7) 40 to 50 LPs waiting to be "zero-paisa" cleaned.

8) SME 3012 - need to purchase parts to make it functional on the L75.

9) Cartridge experimentations - done, finito, khalaas.

10) Cartridge retip - my Ortofon Kontrapunkt c and Ortofon MC 20 are waiting to be sent off for retips.

11) Ortofon MCA 76 MC phono stage - waiting for complete overhaul (it plays but the sound is very, very bright).

Adding:

12) One fancy unbalanced interconnect (not mine) waiting to be repaired.

Adding 2: how can I forget the Super Simple Pre!

Adding 3: just completed a 1.25m pair of unbalanced ICs made using REAN RCAs and RG 176 double shielded coax cables for a fellow forumer to be used as phono interconnects.

 

[jls001]

Hi Joshua,
I am using DPST switch.You got the correct DPDT switch.Please find below pic for your switch.You can leave upper or lower terminals,but middle should be used.

Regards,
Sachin

@Sachin: I managed to fit the DPDT. The diagram is slightly confusing and I ended up making a wrong connection (and almost blowing up one battery). I will make a clearer drawing and upload a picture.

 

[jls001]

Below is the colour-coded diagram for wiring up DPDT switch having three legs x 2 rows:

 

[sachu888]

Thanks Joshua for detailed diagram.My pic was same but I am not good at drawing
I have saved this pic for CNC building manual.
Regards,
Sachin

 

[Sunderpalanivel]

HI Guys, Just for my knowledge, how long does the battery lasts ?

 

[gopib]

HI Guys, Just for my knowledge, how long does the battery lasts ?

Batteries in my CNC MM Phono stage nearly lasted for about 35hrs. These were the green chinese ones....forget the name...

 

[vktarun]

Hi,

Just completed OPS and will power up CNC this Saturday with OPS

Any suggestion as to what should be the Ideal supply voltage to CNC?

OPS has option from +/-9 Volt to +/-15Volt

regards,

Vipin

 

[sachu888]

Hi,

Just completed OPS and will power up CNC this Saturday with OPS

Any suggestion as to what should be the Ideal supply voltage to CNC?

OPS has option from +/-9 Volt to +/-15Volt

regards,

Vipin

You can use +/-12 for Opa2134.

Regards,
Sachin

 

[sachu888]

Another CNC alive and singing http://www.lencoheaven.net/forum/index.php?topic=9021.30

Regards,
Sachin

 

[sivasarjun]

One of my friends a tv mechanic built it for me.However when i connected it is not sounding right.There is some sort of hum.Is it some sort of grounding problem? My TT has a ground wire and when I touch it to the screw with which the board is connected to a primitive box the humming changes.
Please take a look and diagnose the problem for me.

ImageShack
http://imageshack.us/photo/my-images/855/dsc0006wh.jpg/
http://imageshack.us/photo/my-images/401/dsc0004lg.jpg/
Thank you.

 

[jls001]

One of my friends a tv mechanic built it for me.However when i connected it is not sounding right.There is some sort of hum.Is it some sort of grounding problem? My TT has a ground wire and when I touch it to the screw with which the board is connected to a primitive box the humming changes.
Please take a look and diagnose the problem for me.

ImageShack
http://imageshack.us/photo/my-images/855/dsc0006wh.jpg/
http://imageshack.us/photo/my-images/401/dsc0004lg.jpg/
Thank you.

From your picture:

http://imageshack.us/photo/my-images/855/dsc0006wh.jpg/

it looks like you have not connected 0 Volts point from your battery.

Use below diagram to guide your power connection.

If you are not using DPDT switch, then + of left battery (red line) is +9V point, - of right battery is -9V point (sky blue line). The combined green and yellow line point is 0V (marked G) which is showing unconnected in your photo (unless you have connected from below).

The grounding wire from your turntable is ALSO TO BE CONNECTED TO the point G.

 

[vktarun]

One of my friends a tv mechanic built it for me.However when i connected it is not sounding right.There is some sort of hum.Is it some sort of grounding problem? My TT has a ground wire and when I touch it to the screw with which the board is connected to a primitive box the humming changes.
Please take a look and diagnose the problem for me.

ImageShack
http://imageshack.us/photo/my-images/855/dsc0006wh.jpg/
http://imageshack.us/photo/my-images/401/dsc0004lg.jpg/
Thank you.

Hi,

CNC works on dual Supply, +9, 0, -9. therefore you need to connect two 9 volt batteries.
Also ensure that Turntable Earth is always connected to the CNC earth.


Regards,

Vipin

 

[sachu888]

Hi,

CNC works on dual Supply, +9, 0, -9. therefore you need to connect two 9 volt batteries.
Also ensure that Turntable Earth is always connected to the CNC earth.


Regards,

Vipin

Yes,that is correct.You need to connect 2 X 9V batteries in series to get +/-9V.
You are feeding single supply opamps might get fried .TT ground must be connected with CNC ground wire.I can see cap's leads on CNC board.Caps lead length should be as short as possible.It adds capacitance.

Regards,
Sachin

 

[sachu888]

Wrong post

 

[sivasarjun]

Thanks guys.I had connected only one 9 volt battery.Will show the diagram to my friend.I hope he can make sense of it.