Guide to fix up a Cmoy 2

[jasonhanjk 0]

Yup. You can change R4 and R8 higher.

[Kube 0]

Woohoo! After months of deliberation, my cmoy 2 looks like crap, the most of the drillings on the casing are out of place, and have 2 opamps fried....but the music's great!

 

Currently using 2 opa2227's... instantly heard the increased mid bass to trebles. Btw, what's the amperage for a normal non-rechargeable 9v? I scouted around slt, and the most I can find is a 280mah rechargeable.

[1bit 0]

according to this website, the rated capacity for energizer alkaline 9v battery is 625mAh

 

personally i'm still using an eveready nonrechargeable battery

it's good enough for me and quite cheap ($2)

 

btw does anybody know where to get a good and cheap 9v chargers?

[arc_sine_squared 0]

Can I install larger caps on the power side? Something like a 2000uF or 3000uF. Will this effect the rest of board in a negative way?

[squalle 0]

you can if you want to

 

but can you afford the space?

and why would you need a 2000uF?

1000uF would be adequate IMO

 

 

[arc_sine_squared 0]

I have some parts and pieces left over from another project. In that stash I have a pair of 2200uf and a bunch of 3300uf. I was just curious if they did anything or made a difference. The 2200uf fit, but the 3300uf don't without extra leads.

 

So will they do anything, or will they hurt the circuit in any way?

[jasonhanjk 0]

It should not hurt it. You can give it a try and hear whether the sounds improve.

[69CamaroSS396 0]

I've ordered 2 pcbs from Jason and I'm getting my parts together. I have encountered a problem with getting the specific Alps pot. Mouser currently has it listed as a "non-stock" item which, if I understand correctly, requires a purchase minimum of 1000 pieces. I realize I can use other pots, but sure would like to take advantage of mounting it on the board. Anyone know of another Alps "drop in" replacement, or perhaps another source for the RK09L12B0A31 in the USA? I've done an exhaustive search on the www, with no luck. I apologize if this has been covered already. I haven't completed reading through the entire 30 pages of this thread just yet.

 

Thanks, Greg

[neutralzz 0]

I've ordered 2 pcbs from Jason and I'm getting my parts together. I have encountered a problem with getting the specific Alps pot. Mouser currently has it listed as a "non-stock" item which, if I understand correctly, requires a purchase minimum of 1000 pieces. I realize I can use other pots, but sure would like to take advantage of mounting it on the board. Anyone know of another Alps "drop in" replacement, or perhaps another source for the RK09L12B0A31 in the USA? I've done an exhaustive search on the www, with no luck. I apologize if this has been covered already. I haven't completed reading through the entire 30 pages of this thread just yet.

 

Thanks, Greg

hi greg,

 

you could probably try out

 

http://www.ampslab.com/accessories.htm

 

he has a few different alps there.. does international shipping too

 

the 50k pot he has might be able to fit, probably ask for the "width" of the pins from someone here and email it to michael to confirm the dimensions..

 

paypal and all should be pretty convenient

[69CamaroSS396 0]

Thanks neutralzz. I'll give that a try.

 

Greg

[neutralzz 0]

one thing, if you are getting from ampslabs dont forget to ask if you could be exempted from the $15 handling fee he charges for amplifier kits etc... cuz he has to sort out lots of parts

 

you're just buying a couple of pots wouldnt need much packaging nor sorting out

[linksix 0]

Finally got mine made up. Definatly needs tweeking - it doesn't sound all that loud, a wee play about with the gain should sort that out. The only thing I blew was the LED (not too bad for my first attempt ).

But I came across a cheap set of mini speakers for mp3/cd etc players - anyone know how easy it would be to use this inplace of the headphones, think it was rated at 2-3 ohm. Would any modification be required?

[jasonhanjk 0]

You should not have to make any modification to drive these mini speaker.

 

Hmmm. Mouser has stop stocking up the 9mm alps. Let me see what I can do.

[neutralzz 0]

Finally got mine made up. Definatly needs tweeking - it doesn't sound all that loud, a wee play about with the gain should sort that out. The only thing I blew was the LED (not too bad for my first attempt ).

But I came across a cheap set of mini speakers for mp3/cd etc players - anyone know how easy it would be to use this inplace of the headphones, think it was rated at 2-3 ohm. Would any modification be required?

2 or 3 ohm speakers.. are the toughest to drive.. draws a lot of current.... i would suggest not trying to drive the speakrs with the cmoy2..

[69CamaroSS396 0]

 

Hmmm. Mouser has stop stocking up the 9mm alps. Let me see what I can do.

Anyone know if there would be any problem with using the RK097 Alps that is switched? I have a few of those I bought from Tangent. I was thinking the tabs for the switch could be snipped off. It looks as though the pot is otherwise identical to the one recommended for the pcb. Someone correct me on that if I'm wrong. Or I could just use one of those and panel mount AND use the switch. Just tossing around some ideas.