My F4 Build

[william2001]

Einric, I've sent you a PM...

[Einric]

I have JFET's on the way from Spencer.

[Einric]

Well......It looks like I am at a bit of a stall on the PCB's.
I'm hoping the rest of my parts from Mouser will arrive on Friday so I can complete the PCB's minus the JFET's.

Now I guess I will move on to the chassis.
I will fan cool these with each heatsink having 2 120mm fans for a total of about 100CFM per side.
These are not the fans I will be using but they represent the size of what I will use.
I'm hoping that will make up for my heatsinks only being 5" tall.

[The Space Egg Corp]

Hi Einric

Sorry to hear Santa Claus was peddleing fake gear !!!

So...I take it the 74's fronts, looked 'sanded' ?

Those 'V' 170's @ 2mA...now THATS NOT a Bingo !

You should press-hard for a refund on E-Bay...
...I did on the ringer's I was sent ! ( and got it )...
...The good thing about E-Bay is, you can actualy apply a bit of ( polite ) pressure on 'rouge sellers' & get a result.

I don't think the seller I bought from was actualy aware the 74's were fakes...Mmmm...
...Maybe they were just good at faking, they didn't know about the fakes !
Just tell 'em the FBI will add them to some kind of nasty list !
$$$'s back el sharpo, I wouldn't wonder !

One dude on the site's '10 Most Wanted' page...
...had a tranny draw 100mA and EXPLODE in his face !!!
I might even start wearing some Wayfarers for testing, having read that ! ...
...Whilst listening to Don Henley, of course !

Einric...
...check out 'Akasa' ultra-quiet computer-fans ( they, the BEST ).
I have 120mm ones, 7 orange-blades, ball-races, & fully machine-balanced !...
...lots of CF/M...absolutely NO NOISE !
I've done A LOT of high-power PSU ventilation professionaly...
...these funky Akasa fans, are the best I've ever seen...
...ain't too expensive either.

Cheers.

Si.

Happy New Year !

now....
....where's Spencer got to..............

[Einric]

I was looking at the Arctic Cooling F12 Pro.
They are 54cfm at .5 sone, I was already looking at using some type of thermal sensor to adjust fan speed and bias current for max bias at 50-55 degrees.

We'll see about the chassis as things progress.

[The Space Egg Corp]

Hi Einric

Have you got the schematic you're working from ?
In JPG or PNG etc...
... that you could post HERE.
Would be interesting to see it.

Cheers.

Si.

[The Space Egg Corp]

Hi Einric

2 comments on the fan.

1. 'Fluid Dynamic Bearing' ?
What the dar.gon. is that ?
Ball-bearing is what's needed, surely ?
I hope 'FDB' is not an acronym for 'CHEAP' !

2. Not in a standard fan 'form-factor'.
Possibly makes it difficult to atatch things from both-sides...
...ie. suck OR blow...
...and ducting/guides etc.
Also possibly difficult to REPLACE if need be.

Just a thought.

Cheers.

Si.

Dunno how prices on these fans are in the USA.
Sometimes things are cheaper than in the UK.
Based on UK £'s - USD $'s @ about 1.6 USD/£
The 'Akasa' fan would be about $16.
Mmmm...

[Einric]

Fluid Dynamic Bearing is a technology invented by Sony that floats the motor in a magnetic fluid type thing that eliminates the need for a physical bearing.

I only need to attach it as a "Blow" fan so no biggie there.
At $5 US each they are cheap and well reviewed on the Net.
If I need to replace them I will just use standard 120mm fans on an LM317.

Here is the schematic.

[The Space Egg Corp]

Looks like hi-tech stuff Einric...
...I'm sure those boffins @ SONY have got it nailed !

Cheers.

Si.

How much Volts & Current ?
ie. total dissipation on each sink ?

[Einric]

I will be running +-24V ish, with probably somewhere around 500mA to 1A of bias per device I believe.
I'm basically following the DIY Audio F4 Build thread for my information.
The main difference being I will be using bypassed Panasonic FM capacitors instead of the Silmic II's.
Current all depends on heatsink temperature 50-55 degrees C.