My F4 Build

[william2001]

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

 

[Einric]

I have JFET's on the way from Spencer.

 

[Einric]

Chassis Work

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.

 

[Einric]

I also ordered TO-92 heatsinks for the little 3-legged bugs onboard.
I don't know if they are needed but I figured it couldn't hurt.

 

[Einric]

Wouldn't Ya know it, My order is lost in the mail.
My Postlady has no idea where it is but they do admit it made it's way through the sorting at the local post office.

 

[6L6]

Bummer news.

What was in the package? Are you stuck building until you get it?

 

[Einric]

It is the capacitors & large resistors.
I don't have any of the power supply parts ordered yet, I'm still not quite sure how I will arrange it.

 

[6L6]

Do you have a PSU circuit board?

What are the dimensions of the caps you ordered?

 

[Einric]

I will be P2P on the P/S, I will either use some perf board for the TO-247 rectifiers or I will just mount them to heatsinks and hot glue them upside down.
I have ordered Panasonic FM's for the onboard caps and I was looking at CDE SLPX (25.4 x 40) or Panny TS-HA (25 x 45) for the P/S caps bypassed with my leftover FM's and some Evox MMK's I have salvaged.

 

[lhgin]

fake transistors?

Einric,

I was about the decide on the F5 kit from HKAUDIOPARTS eBAY and luckily I read this thread. So it is confirmed that the transistors are fake?

Ken

 

[Einric]

Well....The supplier swears that they are genuine.
Unfortunately they just don't test how they should.
They did give me a refund but I just don't know?????

 

[lhgin]

perhaps he does not even know whether they're genuine or fake. what a sad case.

 

[Einric]

Finally Mouser has shipped a replacement order Free Of Charge.
Great to see they are willing to make things right.