F5 power amplifier

[GRollins]

One of the most valuable things you can do when you're laying out a PCB is to put it down and come back to it the next day. Better still, two or three days later. You'll see all kinds of things that can be done better. Sometimes you even catch mistakes.

Grey

[jackinnj]

and when you mount the power resistors -- put them at least 1/4 to 1/2 inch above the board as they are gonna be cookin'

[Variac]

It sems that the power resistors could be spread apart a bit more to help with cooling...

[Audiofanatic]

Originally posted by GRollins
One of the most valuable things you can do when you're laying out a PCB is to put it down and come back to it the next day. Better still, two or three days later. You'll see all kinds of things that can be done better. Sometimes you even catch mistakes.

Grey

I second that!


Cheers,


Audiofanatic

[Magura]

Originally posted by twitchie

I'm just not looking forward to the next part - drilling holes.

With any luck ( and wife + 2-year old permitting), I may just have this thing stuffed and singing before summer's over

Thank you Nelson Pass for your immeasurable contributions to this hobby!

Drilling PCB's is a walk in the park.

I would not change anything, but simply just stuff the boards, and see IF any problem at all should arise, but I doubt it should cause you trouble.


Magura

[Babowana]

Originally posted by GRollins


One of the most valuable things you can do when you're laying out a PCB is to put it down and come back to it the next day. Better still, two or three days later. You'll see all kinds of things that can be done better. Sometimes you even catch mistakes.

As I am seldom satisfied with my own PCB work, I do approach in
different way. I darw all paths on the paper with pencil and check
them wether all are going to right directions and branches.
And, if I am sure of that, I just make the PCB and finish all at the same
time. I do not want to cry over my ever-ugly PCB works...
But, the impovement is possible for the second try... third try...

[Bill Fuss]

Hey Twitchie,

I've been studying your board layout and you've done a fine job, but I found a little error in the feedback loop. R1 and R2 should be 10 ohms, not 10K, and should probably be 3W also.

I'm still looking but nothing else jumps out at me right now.

Also, on the traces around the 240, it would be better to locate R14 much closer to the gate pin and pass the source trace under it.

Keep it up, you're lookin good.

Bill

[sandstorm33]

Originally posted by Babowana




As I am seldom satisfied with my own PCB work, I do approach in
different way. I darw all paths on the paper with pencil and check
them wether all are going to right directions and branches.
And, if I am sure of that, I just make the PCB and finish all at the same
time. I do not want to cry over my ever-ugly PCB works...
But, the impovement is possible for the second try... third try...

Once the music starts where's UGLY then???

Twitchie..no need to make the 10ohm resistors 3w. The rest should work just fine. If you do it again consider allowing for choices on the source resistors..I for one have LOTS of Dale 5watters. Also slightly larger pads on the smaller traces aids in solder flow. Good job for the first try.

[jackinnj]

Lateral F5 wiring layout:

[Bill Fuss]

R1 and R2 pass significant current to ground, use at least 1W.
OHM's Law works every time, unless magic is involved.

Bill