diyAB Amp - The "Honey Badger"

[keantoken]

Krisfr, is it possible you can make the text cut out of the ground plane, instead of having to clear space around it? Seems like something sensible any layout program should be able to do.

D104 and D201 still need to be reversed on the schematic and the board.

It looks to me like the input stage CCS is all foobar'd.

- keantoken

[Krisfr]

Originally Posted by keantoken

Krisfr, is it possible you can make the text cut out of the ground plane, instead of having to clear space around it? Seems like something sensible any layout program should be able to do.

D104 and D201 still need to be reversed on the schematic and the board.

It looks to me like the input stage CCS is all foobar'd.

- keantoken

Done on both

[keantoken]

Okay, one other thing. D102 and D103 should be replaced with a red LED, same for D202 and D203. Green LEDs may be necessary, we will just have to see. I use them this way in my K-multipliers and they haven't exploded thus far with 24V rails... This datasheet gives 1A max surge current:

http://www.chml.com/products/pdf/1-78.pdf

Maybe a 470R series resistor would offer adequate protection...

How about input LTP degeneration/offset trimmer? Is that arranged right?

- keantoken

[Krisfr]

I fixed the pot to connect to the resistors. I put a place for a JUMPER!

I will have to work on the Diodes, enlighten me on the diff between the red and the green...

[Krisfr]

FYI on Alex's board there is no connection between R34 and Q13's base.

[keantoken]

The 100k resistor is chosen to be right on the edge. The base current of the bipolar is several uA. This means there is enough voltage across the 100k resistor to forward bias the diodes. When this happens, the diodes conduct and reduce the filtering capability of the regulator. So choosing a diode with higher breakover voltage will improve filtering. Red LEDs give about 1.8V, green ones give about 2.9V. If green is necessary, then I would rather modify the circuit I guess.

- keantoken

[audiofan]

In this circuit there is a " ground breaker " ( D1-D2-R4 ) and star grounding is on the circuit board betwen C17 - C13.

Should the RCA input connector be connected to amplifier case and amplifier case be earth grounded.

This way amplfier ground is made across ground breaker.

Or should the RCA be insulated from case( as done in LEACH ) and ground of the amplifier be made from the circuit board betwen C13 - C17 to case ?

[Krisfr]

Originally Posted by keantoken

Krisfr, is it possible you can make the text cut out of the ground plane, instead of having to clear space around it? Seems like something sensible any layout program should be able to do.

D104 and D201 still need to be reversed on the schematic and the board.

It looks to me like the input stage CCS is all foobar'd.

- keantoken

The text on the ground plane is not working like I want it to. I want to do a board today, but my testing does not warrant doing it. The text is not readable on the printable sheet.

Any suggestions?

[keantoken]

Well, you could remove all the text and add the component numbers by hand in white text to the printout file. I'm surprised your layout software doesn't have a suitable feature.

- keantoken

[Krisfr]

Originally Posted by keantoken

Well, you could remove all the text and add the component numbers by hand in white text to the printout file. I'm surprised your layout software doesn't have a suitable feature.

- keantoken

Great Idea and I forgot that the program has a WHITE layer, so It can work... Details at 11...