• These commercial threads are for private transactions. diyAudio.com provides these forums for the convenience of our members, but makes no warranty nor assumes any responsibility. We do not vet any members, use of this facility is at your own risk. Customers can post any issues in those threads as long as it is done in a civil manner. All diyAudio rules about conduct apply and will be enforced.

Gb: F5 Pcb

Status
Not open for further replies.
Jump to Latest
#702
Diodes, use any three legged with Anode Cathode Anode legs. Example:
http://www.mouser.com/Search/ProductDetail.aspx?qs=sGAEpiMZZMtEwUVCuofpuJ8elz361Z6mD/We128j0pc=
(you can also use two legged, but then you need to bend the legs slightly)

Heatsinks, if you want to use onboard sinks use these:
http://www.mouser.com/Search/ProductDetail.aspx?qs=wT7LY0lnAe0UzSGKJGAHIA==

For the snubbers (resistor and capacitor) you can use 100ohm and capacitors in the 20-100nF range.

And of course you will need to buy 4 of each for one board.
 
#703
Hi Christian,

I'm hoping someone can help me troubleshoot my F5. The amp (built with your boards) has worked fine for many months. Sounded great in fact. Suddenly while playing music it stops and begins to buzz in both channels.

A quick check shows the 24v DC at the outputs. No visible damage to the boards but I can't keep it powered on for more than 20 sec or so.

What would be the best way to proceed? Thanks in advance.

Ron
 
#704
:bawling:

What happens after 20 sec? (don't connect speakers)

Do you have replacement components?

You have to start trouble shooting. If nothing burns when it is on, you can start to measure voltages - otherwise you have to figure out which component is shorting the whole thing (you solder out the power fets).
 
#705
No speakers connected. Tested with inputs shorted and open. After 20 sec I start to smell burning. Power supply tests ok when disconnected.

I do have a second set of boards and components. I will build those while I troubleshoot these.

What doesn't make sense to me is that something happened to both boards at the same time.
 
#713
Back at Pass

Hi Christian,
From your Jan. GB: I've been distracted lately with putting together/equipping a varily decent build/test bench: Just current with thread. Curious; the new PCB-3/13/09, Is only change to Q5 silk?

Also, new Rect.B PCB---2 diode bridges, etc. vs PCB. Is improvement because of 'better' ultra fast recovery of To-247 devices like MUR3020W? Or is mainly just to simplify/organize PS input? On brd heatsink option a +plus if needed; yes but I'm using big Conrads with plenty of surplus 'sink' for To-247 RBs . If no real advantage, RectB PCB seems more costly? Just curious, cause cuz last GB you only had 1/2 of PSU brds I needed so I got a couple of Peter's PSBs with snap off RB chips. Just considering my PS options.
Thanks

Charles
 
#714
Re: Back at Pass

cowboy99 said:
Hi Christian,
1. From your Jan. GB: I've been distracted lately with putting together/equipping a varily decent build/test bench: Just current with thread. Curious; the new PCB-3/13/09, Is only change to Q5 silk?

2. Also, new Rect.B PCB---2 diode bridges, etc. vs PCB. Is improvement because of 'better' ultra fast recovery of To-247 devices like MUR3020W? Or is mainly just to simplify/organize PS input? On brd heatsink option a +plus if needed; yes but I'm using big Conrads with plenty of surplus 'sink' for To-247 RBs . If no real advantage, RectB PCB seems more costly? Just curious, cause cuz last GB you only had 1/2 of PSU brds I needed so I got a couple of Peter's PSBs with snap off RB chips. Just considering my PS options.
Click to expand...

1. And I have added a pin header footprint for the LED - but you're right - nothing serious.

2. Well lots of people have asked for these, and they make it easy to use ultra fast recovery diodes and supply more current for bigger amps. In fact I consider them of general purpose nature - and not directly related to the F5, although it seems like an upgrade well worth it.
 
#718
Some informations from Nelson PASS about Power Supplies :
http://passlabs.com/articles.htm
Download the PDF and read the section about Recifiers.

"Yeah, sure, rectifiers are important, after all, the AC has to get converted to DC, but I don't like the fast recovery types that some audiophiles have raved about. Fast recovery means that they withstand many amps and volts in a tenth of a few nano-seconds, something we don't see very often on the old 60 Hz AC line. They are essential element in switching power supplies, but for regular "linear" power supplies, I much prefer SLOW diodes, and we create them by placing small capacitor circuits across the diodes, which greatly reduces radiated noise."

Just wondering about the caps type and values... 😉
 
#719
korben69 said:
Some informations from Nelson PASS about Power Supplies :
http://passlabs.com/articles.htm
Download the PDF and read the section about Recifiers.

"Yeah, sure, rectifiers are important, after all, the AC has to get converted to DC, but I don't like the fast recovery types that some audiophiles have raved about. Fast recovery means that they withstand many amps and volts in a tenth of a few nano-seconds, something we don't see very often on the old 60 Hz AC line. They are essential element in switching power supplies, but for regular "linear" power supplies, I much prefer SLOW diodes, and we create them by placing small capacitor circuits across the diodes, which greatly reduces radiated noise."

Just wondering about the caps type and values... 😉
Click to expand...


Papa has changed his mind since that article, I have read it several times in the pass labs forum, but my search only gave this reference:
http://www.diyaudio.com/forums/showthread.php?postid=321830#post321830


This may also be an inspiration:
http://www.diyaudio.com/forums/showthread.php?s=&postid=17199&highlight=#post17199
 
Status
Not open for further replies.
Top Bottom