Snob-Bob Fancypants can invest another 75 cents per board, for 250Vac higher voltage rating and 8 times lower DF.
Exactly fits the 6mmx13mm footprint on the board : Siemens/Epcos B32921
Personally, i just like 'm cause they're Blue and had enough of them for the two 10-er boards i got from Jens.
Exactly fits the 6mmx13mm footprint on the board : Siemens/Epcos B32921
Personally, i just like 'm cause they're Blue and had enough of them for the two 10-er boards i got from Jens.
IIRC, http://www.mouser.com/Search/ProductDetail.aspx?qs=qOqV1E1P08Qnk025MRBEEA== should work - check the data sheets and measure the board - I think the lead spacing is ~22 mm which this one would fit. I used a different one from Digikey which doesn't seem to be availble anymore.
Re: searching components for best quality/price rate
Giuseppe, your resistor values in the front end (R6 R7 R9 R10 etc) stray from Jens posted BOM, where you have specified 300R instead of 330R. Please explain this discrepancy.
As I'm ready to build up my first PCB, I need to know what effect (however marginal) this will have on function of the build.
Regards, Rob
AudioG said:While I waited for the arrival of the pcbs, I am searching the components, so I have prepared a datasheet that could be useful to others.
Ciao, Giuseppe.
Giuseppe, your resistor values in the front end (R6 R7 R9 R10 etc) stray from Jens posted BOM, where you have specified 300R instead of 330R. Please explain this discrepancy.
As I'm ready to build up my first PCB, I need to know what effect (however marginal) this will have on function of the build.
Regards, Rob
Re: Re: searching components for best quality/price rate
300r is specified by Leach and discussed in detail in the section covering linearity of the input stage and how degeneration influences this.rob3262 said:Giuseppe, your resistor values in the front end (R6 R7 R9 R10 etc) stray from Jens posted BOM, where you have specified 300R instead of 330R. Please explain this discrepancy.
Re: Re: Re: searching components for best quality/price rate
Merry X-mas....
I chose the 330 Ohm value as this is a standard E12 type.... 300 Ohm may not be as easy to get....
\\\Jens
AndrewT said:
300r is specified by Leach and discussed in detail in the section covering linearity of the input stage and how degeneration influences this.
Merry X-mas....
I chose the 330 Ohm value as this is a standard E12 type.... 300 Ohm may not be as easy to get....
\\\Jens
Hi Jens, Rob & AudioG,
There's nothing wrong with adopting 330r for 300r in the input stage, It's only 10% after all.
Rob asked, why AG reverted to 300r and it appeared that Rob had not bothered to read up on the Leach. Prof Leach gave us all this good design info for free and yet some refuse to read it.
There's nothing wrong with adopting 330r for 300r in the input stage, It's only 10% after all.
Rob asked, why AG reverted to 300r and it appeared that Rob had not bothered to read up on the Leach. Prof Leach gave us all this good design info for free and yet some refuse to read it.
Merry Christmas!
Hi All!
Just wanted to say I'm now home recuperating and everything is fine(except I have to stay off my foot for a few weeks-darned crutches!).
Thanks for the kind wishes.
Also, I got another pair of PCB's(since I'd already started soldering components on mine, I didn't have an empty board to use for indexing the heat sinks!), and all the heat sinks in the current order are spoken for.
I wish all my friends* here a Merry Christmas/Hanukkah, etc, and a Happy New Year!!
-Chas
*special greetings and thanks to Jens, Tad, Ray, Carl, Fred and Bill
Hi All!
Just wanted to say I'm now home recuperating and everything is fine(except I have to stay off my foot for a few weeks-darned crutches!).
Thanks for the kind wishes.
Also, I got another pair of PCB's(since I'd already started soldering components on mine, I didn't have an empty board to use for indexing the heat sinks!), and all the heat sinks in the current order are spoken for.
I wish all my friends* here a Merry Christmas/Hanukkah, etc, and a Happy New Year!!
-Chas
*special greetings and thanks to Jens, Tad, Ray, Carl, Fred and Bill
There's a lot of information to absorb on this project, and many sources for reference material. I will re-read Mr. Leach's documentation, thank you Andrew for pointing me back to this source.AndrewT said:Hi Jens, Rob & AudioG,
There's nothing wrong with adopting 330r for 300r in the input stage, It's only 10% after all.
Rob asked, why AG reverted to 300r and it appeared that Rob had not bothered to read up on the Leach. Prof Leach gave us all this good design info for free and yet some refuse to read it.
With regards,
thermal track pcb
I noticed that the Thermal tracking diode PCB's in this latest group buy are plated thru-hole to unmasked pads on the bottom side.
As seen in the PCB photo on Jens' Delta-Audio website, the pads should have been omitted. These bottom side pads can short out to the heatsink when mounted.
So, best way to remove the pad? Take Exacto knife and scrape 'em off, or hit it with a hot iron until the pads lift?
I noticed that the Thermal tracking diode PCB's in this latest group buy are plated thru-hole to unmasked pads on the bottom side.
As seen in the PCB photo on Jens' Delta-Audio website, the pads should have been omitted. These bottom side pads can short out to the heatsink when mounted.
So, best way to remove the pad? Take Exacto knife and scrape 'em off, or hit it with a hot iron until the pads lift?
The first batch of boards did not have pads on the bottom of the diode boards. It sounds like a manufacturing error since Tad just reordered - the first I've heard of from Advanced. Maybe they'll give us a break on the next buy.
I'll grind the pads off with a Dremel. If you have a sheet of mica or some Kapton tape, you can just insulate them.
I'll grind the pads off with a Dremel. If you have a sheet of mica or some Kapton tape, you can just insulate them.
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