AB100 Class AB Power Amplifier

[neno70]

hi, did someone make the pcb with the Pope's gerber and a couple of them to sell? thank you

 

[jwjarch]

More boards on the way!

Howdy. I just shipped some PCBs from California USA to international destinations. I wrapped each board tightly in photocopier paper (to prevent surface scratches) and mailed them in "#2 Bubble Mailer" envelopes which I bought (here).

When I trotted the mailers down to my local US Post Office, the clerk told me I could send the parcels using First Class Package International Service. This costs about USD 14.50 and varies a bit depending on weight and distance to destination. Attached below is my receipt from shipping a bubble mailer containing 3 PCBs, to a diyAudio member in South Africa.

This service does NOT include package tracking or insurance, and you DO need to fill out the postal service's Form 2976-R which is the US Customs declaration. "Gift" "PCB Sample" "Total Value=$4.00" appears to get the board to the recipient with a minimum of extra hassle at their end.

_

This is great Mark! Thank you for sharing your shipping experience. I just placed an order for 20 boards with JLCPCB. I've done several board runs with them and have always had great results. The boards are as listed previously.

2mm Thick FR4
Red Solder Mask
2oz Copper
ENIG Finish
$7 per board plus packing and shipping (international tracking and insurance would be extra if you want them)

PM me if your interested. I accept PayPal. I should have the boards in hand around the end of next week.

Between this and FreeCrowder's order we should be able to get a few more AB100's up and running.

Thanks again to Papa Pass for his generosity!!!!!

 

[Freecrowder]

Just so everyone knows my boards are the same cost but they aren't quite as good as far as the thickness and copper. Mine will be 1.6mm and 1OZ copper. the same quality from where I ordered doubled the price. Should still be quite good for the job though.

 

[Freecrowder]

How are you guys getting these boards at 2mm and 2oz copper so cheap!! I run them through 2 different places and can only get down to 10-11 bucks for 20.

 

[Skylar88]

Ordering 20 boards from JLCPCB + shipping from Hong Kong with Aramex Global Shopper works out just under $7 each.

That's for 2mm FR4, 2oz copper & ENIG finish.

 

[uchu007]

You use what as output transistors? tip142/147 or other things? Too bad that can not with std03n/ std03p because I like these transistors, I have already made a montage with the LME4702and are it is beautiful

 

[osscar]

I think they can be used - of course you will need custom pcb and 2-3 pairs will be enough...

My reduced AB 100 to AB 60 is slowly being processed- still have to make PCB and wait for the parts to be delivered...

 

[prasi]

no reply yet anyone for post #553?

I am just a 'dime a dozen' PCB designer (and very bad at it too!). I sometimes wonder at why I am messing around threads for and by intellectuals

regards
Prasi

 

[ubergeeknz]

no reply yet anyone for post #553?

I am just a 'dime a dozen' PCB designer (and very bad at it too!). I sometimes wonder at why I am messing around threads for and by intellectuals

regards
Prasi

If you're referring R35 it's been mentioned a few times ... Consensus seems to be it's not necessary. Although I didn't see Mr. Pass chip in.

 

[prasi]

If you're referring R35 it's been mentioned a few times ... Consensus seems to be it's not necessary. Although I didn't see Mr. Pass chip in.

Hello uber,
I was wondering if something like this can be done, with R35 being used to lift input ground, R2 ground and NFB cap ground by 10 ohm resistor from the PSU ground.
regards
Prasi

 

[ubergeeknz]

Hello uber,

I was wondering if something like this can be done, with R35 being used to lift input ground, R2 ground and NFB cap ground by 10 ohm resistor from the PSU ground.

regards

Prasi

No idea.

 

[Nelson Pass]

Yes, you can do that.

Usually the idea is to break a ground loop in an two channel amplifier having
common input ground. Magnetic fields inside the amp and outside can cause
current to circulate from one channel ground back to the source and then
back to the amp via the other channel's cable ground and ultimately causing
noise pick up. If you break one channels input ground connection and replace
it with a 10 ohm or so resistor, you can break that loop.

Doesn't always work, but easy enough to try.

 

[Skylar88]

Hello uber,
I was wondering if something like this can be done, with R35 being used to lift input ground, R2 ground and NFB cap ground by 10 ohm resistor from the PSU ground.
regards
Prasi

Hi Prasi
If you're working on a layout, I hope that you're going to share the Gerbers.

 

[jwjarch]

Hi All,

I currently have 6 boards (3 stereo pairs) left if anyone is interested. I should receive the boards on Wednesday, but I probably won’t have time to ship out until the following week due to the holiday.

 

[jwjarch]

Boards came in a day early! DHL from Shenzhen is amazing! They turned out fantastic. Each boards weighs 2.75oz. This was a heavy package. I have one pair of boards left. If anyone is interested, PM me.

 

[Nelson Pass]

That's two good vendors.

I remember the days when I had to tape this stuff up, have it photographed
to separate blue/red/black and send that off.

Only took a month and $1000 for a single prototype...

Who sez there's no progress?

 

[jwjarch]

Pretty amazing stuff NP! Thanks again for the great design and the gerbers!

FYI, all of my boards are now spoken for. Thanks everyone!

 

[Freecrowder]

So I'm stuffing my first board and I want to clarify some values. I understand value and multiplier but still have some questions. Base resistors are 221. is that 22x1Multi equals 220ohm? Also R7 2210 221x 0 multiplier equals 221ohm? R5= 475 ohm?

 

[6L6]

I'd agree with your assumptions. 221ohm on base, 2210=221ohm, 4750=475ohm

 

[jwjarch]

Post some pics when you get a chance Freecrowder. What are you using for a case and heatsinks?