CMoy - Pocket Headphone Amp !!

[Audiodoc]

You just need a ic base and know the right pin configuration. The pin with the dot marking is pin 1, rest of the pins counting counterclockwise. Resistor values can be clarified from diyaudio forum or head fi.

 

[anuragn]

I bought 10 pc of Resistors in each value and now they're mixed up.
I've tried using an android app to check their values with color coding but I feel it isn't foolproof, will a multimeter help ?

Multimeter is a must for a DIYer. Even the cheapest one costing Rs 150/- is enough for basic needs.
Also, memorize the colour coding system of resistors so that just by looking at one, you should be able to read its value. Its not too hard

 

[Audiodoc]

BB ROY GB VGW
Black brown Red Orange Yellow Green Blue Violet Grey White
0123456789

Mnemonic: BB ROY Great Britain Very Good Wife

 

[novice-akki]

BB ROY GB VGW
Black brown Red Orange Yellow Green Blue Violet Grey White
0123456789

Mnemonic: BB ROY Great Britain Very Good Wife

Doc, is this a way to memorize resistor values with color coding ?

Also which side of PCB should have solder joints, shiny side or the other ?



Sent from Samsung Galaxy Note II GT-N7100

 

[Audiodoc]

Yes this is for the resistor values. The shiny copper side. I had recommended a ready made PCB which will make work easy for you.

 

[jls001]

PCB I have is similar to this hope it'll suffice.

I've been looking at all this stuff since day before yesterday don't really know where to start or should I start at all

OK, it looks like you chose to start off with the second most basic way of rigging up a circuit using a bread board. The most basic way would be point to point wiring (I think).

That leaves you with little choice but to know for sure some basics so that you don't blow up anything :

1) understand -ve and +ve terminals of polarised devices like electrolytic capacitors, and make sure that you connect them the right way as indicated in the circuit, or risk an exploding capacitor (has happened to me!).

2) Correctly identify and connect -ve and +ve terminals of input and output signals, and power supply. You are going to deal with DC power so -ve and +ve is critical.

3) if your circuitry involves diodes, make sure they are correctly connected. If you reverse a diode, you have an infinite resistance and no current will flow, so it will be as good as an open circuit.

4) if your circuit has any transistors - whether BJTs or FETs or MOSFETs, the three legs (terminals) must be correctly connected.

5) Opamps or any other chips: use an adaptor that you can solder to the board. Plug in the opamp later. You can remove opamps without desoldering (and enjoy opamp rolling). Since you are using a bread board, you need to wire up all the 8 terminals to the relevant points in the circuitry! Look out for the notch on the opamp. Holding the opamp with the notch facing your left, the pin just below the notch is pin 1.

 

[arunlouie]

Hey Akki,

I have a CMOY PCB lying unused. I tried building it and then lost interest. Collected altoids case and most of the parts as well. If you want I can send it for free.

CMOY Board : JDS Labs - cMoyBB v2.03R PCB - Rechargeable

/Arun

 

[novice-akki]

Many thanks for your kind gesture...I'd really appreciate if you can ship it thru...will happily pay for shipping and any extras.

Please let me if its possible so I can send you my details.

Sent from Samsung Galaxy Note II GT-N7100

 

[novice-akki]

Just noticed the pot I've is not dual it has only 3 terminals can I just bypass it and control volume from phone or mp3 player ?

Sent from Samsung Galaxy Note II GT-N7100

 

[arunlouie]

Many thanks for your kind gesture...I'd really appreciate if you can ship it thru...will happily pay for shipping and any extras.

Please let me if its possible so I can send you my details.

Sent from Samsung Galaxy Note II GT-N7100

NP, Please PM me your address.

 

[novice-akki]

I've soldered the components as they are in this image with reference from this schematic

How do I connect all the components together I mean continuity, the project I'm following has used a different board than mine, in the image link above the components are joined using jumpers should I also make the same jumpers?

Also, the volume pot I've isn't dual so can I bypass it in this build and in the next CMoy I can have dual pot ??

Please revert can hardly wait...

 

[Thad E Ginathom]

It is nice to see some of the better-than-pro stuff built by our expert DIYers, but seeing someone taking first steps is also great. Might be an inspiration for some us to do the same, one day, instead of just looking at the massive power amps in beautiful cases, drooling, and thinking, "But I could never..."

Thanks for posting your continuing adventure!

 

[novice-akki]

It is nice to see some of the better-than-pro stuff built by our expert DIYers, but seeing someone taking first steps is also great. Might be an inspiration for some us to do the same, one day, instead of just looking at the massive power amps in beautiful cases, drooling, and thinking, "But I could never..."

Thanks for posting your continuing adventure!

^^I thank you for these encouraging words honestly means a lot, I'll continue with my adventures and sorry for a late post, couldn't turn a deaf ear to monk's call

 

[Audiodoc]

One of the forum members had used the vero board beautifully for his circuits. He used the small pieces of wire cut from the ends of resistors or capacitors or simply bending them. You can cut open a LAN cable to get solid core copper wire too.

 

[Thad E Ginathom]

You can cut open a LAN cable to get solid core copper wire too.

I'm digging here, ten years back: aren't cat5(-etc) flyleads supposed to be twisted? For flexibility?

I have a dim memory of a real network engineer telling me that the reason my hand-crimped cables didn't work was that I was using the wrong cable. It is indeed a dim memory, and I don't have any known-not-to-work flyleads to cut up.

 

[novice-akki]

One of the forum members had used the vero board beautifully for his circuits. He used the small pieces of wire cut from the ends of resistors or capacitors or simply bending them. You can cut open a LAN cable to get solid core copper wire too.

Doc, I've a few resistor and capacitor snipping's with me and also have a single strand cable that can be put to use, now if only someone can take a look at the schematic and picture I posted and tell me what gets connected with what to have a working amp !!

Waiting...

 

[novice-akki]

I'm getting correct reading when connecting ground to v+ and v- which is 4.4 volts in positive and 4.4 volts in negative...but when I add jumpers to connect the amp's v+ and v- to that of board I get incorrect readings...the amp am using is lm386

Please ignore the upper half of the board as its a failed attempt.



Sent from Samsung Galaxy Note II GT-N7100

 

[omishra]

I'm getting correct reading when connecting ground to v+ and v- which is 4.4 volts in positive and 4.4 volts in negative...but when I add jumpers to connect the amp's v+ and v- to that of board I get incorrect readings...the amp am using is lm386

Please ignore the upper half of the board as its a failed attempt.



Sent from Samsung Galaxy Note II GT-N7100

Dear friend, not able to understand your build. Please take a clue from here. Build it clearly using cat5 cable strands. And post hi res pictures. Many could jump in here.

 

[novice-akki]

I'll have to that eventually...but isnt it true that all 8 pin amps will have different pin configuration which can be had from their data sheet?

Sent from Samsung Galaxy Note II GT-N7100

 

[omishra]

I'll have to that eventually...but isnt it true that all 8 pin amps will have different pin configuration which can be had from their data sheet?

Sent from Samsung Galaxy Note II GT-N7100

All 8-pin DIP8 package has standard for single opamp/ dual opamp chips. So pin numbers are same for all manufacturers.