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Action B
2010.01.05, 07:33 PM
Here is some of my work.

I'm also working on a FET replacement tutorial of my own.

Here is a sample of my work:
http://farm3.static.flickr.com/2601/3837938514_fda1649031.jpg
http://farm3.static.flickr.com/2737/4248770883_f698b89926_o.jpg
http://farm3.static.flickr.com/2768/4248751519_eb3350a6a5.jpg
http://farm5.static.flickr.com/4026/4248751353_c10022ecf4.jpg
http://farm3.static.flickr.com/2784/4249524024_0758c6452a.jpg

larger sized images below


http://farm3.static.flickr.com/2768/4248751519_eb3350a6a5_b.jpg

http://farm5.static.flickr.com/4026/4248751353_c10022ecf4_b.jpg

http://farm3.static.flickr.com/2784/4249524024_0758c6452a_b.jpg

http://farm3.static.flickr.com/2755/4248751021_0d345c312c_b.jpg

Let me know what you think! If you have any questions about FET work I'd be happy to help. These are all on my Z and an Xmod board.

JeremyC
2010.01.05, 07:54 PM
That is nice work. Very nice..

I'll take photos of my 8858 install (fets bought from Action B), and they look nearly as good, but not quite.

Felix2010
2010.01.20, 12:41 AM
I luv anything that has to do with power - FETs especially. I put a lot of time and research into what Fets I run. What are those Fets you did a 2x2 of on your AM MA010 PCB?

Do you do a lot of Fet work? What is your normal rate? Just curious, Thanks for the info:)

Action B
2010.01.20, 01:38 AM
I luv anything that has to do with power - FETs especially. I put a lot of time and research into what Fets I run. What are those Fets you did a 2x2 of on your AM MA010 PCB?

Do you do a lot of Fet work? What is your normal rate? Just curious, Thanks for the info:)

Those FETs are Fairchild 8858s, they are top of the line!

I have done the FETs on dozens of cars, I've lost count by now. I offer my services to the community here for $10 a layer (FETs included).

2x1=$10
2x2=$20

All of my FET installs have been successful thus far.

I'm also very skilled at lifted FET pad repairs via jumper wires.

for 2.4 boards add $5 bucks due to me having to remove four FETs instead of two.

Half
2010.01.20, 03:48 PM
Action B, have you ever used 8958's?
They're basically the same has 8858, the only difference I could find in the datasheet is that it has less on-power resistence.

Action B
2010.01.20, 04:00 PM
Action B, have you ever used 8958's?
They're basically the same has 8858, the only difference I could find in the datasheet is that it has less on-power resistence.

No, thats news to me. I'll take a look at the data sheet. Thanks for the info! Maybe the 8858 is not top of the line any longer!

I checked that FET. Are you sure you don't have it backwards?

I see that the 8858 is superior in almost every way. Lower on and off resistance and higher amp holding threshold.

Also, though the numbers might be misleading, the 8858 is the newer FET design.

Half
2010.01.20, 05:58 PM
well it happens I got confused,

NDS8858H:
N-Channel 6.3A, 30V, RDS(ON)=0.035W @ VGS=10V.
P-Channel -4.8A, -30V, RDS(ON)=0.065W @ VGS=-10V.

FDS8958A:
N-Channel
7.0A, 30V RDS(on) = 0.028W @ VGS = 10V
P-Channel
-5A, -30V RDS(on) = 0.052W @ VGS = -10V

but on the FDS8858CZ:

N-Channel
􀂄 Max rDS(on) = 17mΩ at VGS = 10V, ID = 8.6A
P-Channel
Max rDS(on) = 20.5mΩ at VGS = -10V, ID = -7.3A

Got confused in manufacturer I guess.
Still I think I'm gonna go for the 8958 since the shop does only have them and the 4562.

Action B
2010.03.13, 11:40 PM
I'd like to announce that I have now removed and stacked FETs on three ASF boards successfully.

I found them no more difficult than the AM boards :)

Here are some pics:

Board with FETs removed, of course, all pads are perfectly intact:
http://farm5.static.flickr.com/4042/4430598807_d5dd542712.jpg

One stack on:
http://farm3.static.flickr.com/2773/4431367598_fc590ba934.jpg

And the second:
http://farm5.static.flickr.com/4072/4431367754_8697ab0a51.jpg

arch2b
2010.03.14, 10:37 AM
nice clean work.

these are the asf 2.4 boards, are the digital 2.4 board any different? you'll get to find out next weekend ;)

Action B
2010.03.16, 08:39 PM
nice clean work.

these are the asf 2.4 boards, are the digital 2.4 board any different? you'll get to find out next weekend ;)

I look forward to it. I'm confident that I can replace the FETs without any damage to the board. As a friend I wouldn't try it unless I was.

Action B
2010.05.16, 08:36 PM
Some pics of my work on Mike Keely's MR-03 from this forum.

Click the pictures to see larger view!

http://farm4.static.flickr.com/3303/4613922008_3dea6b4b95.jpg

(http://farm4.static.flickr.com/3303/4613922008_3dea6b4b95_b.jpg)

http://farm4.static.flickr.com/3352/4613303663_1494b0ff90.jpg (http://farm4.static.flickr.com/3352/4613303663_1494b0ff90_b.jpg)

Action B
2010.12.03, 12:41 PM
I've done several dozens of these MR-03s now, I think its time for some new pictures. I'm going to post some up some new pictures from FET jobs this upcoming tueday at our local hobbyworks track.

arch2b
2010.12.03, 12:45 PM
don't forget i have the computer board for you to work on as well;) it should be easy compared to the spacing/size of mini-z boards.

Action B
2010.12.04, 12:53 AM
don't forget i have the computer board for you to work on as well;) it should be easy compared to the spacing/size of mini-z boards.

Of course Ray, it'll be a nice break to work on something bigger for once.

Action B
2011.05.06, 07:29 AM
Some people have noticed that with my FET work I include a diagnostic test sheet of the tests that I do on each board. These tests are not just something I came up with overnight.

Teaching myself FET work was not easy and it came with a large amount of responsibility. Each fellow racers board is the heart of their car. One slip up on my work and a racer may get a botched board, causing serious inconvenience or worse yet, a blown FET or board during the A main as all of their hard work is putting them in a fighting position for 1st place. Plus its expensive if ever a board was to fry and I was unable to repair. Of course, I would feel obligated to replace in most cases.

I plan on explaining why each test is done and what it accomplishes along with my diagnostic images so that those of you who are interested in doing your own FETs may improve your chances of successful FET transplant and those of you who may be interested in how I do my work can more fully understand what it is I am doing with each board I receive. I think its fairly interesting. Of course, if anyone else has any input on additional testing or other ways of testing, I'd love to hear them as I'm always looking for ways to improve and developing my techniques and evolving my skill to make it more reliable and more thorough (within reason).

Here is a copy of the text from my work, this is not to be reproduced or used at all without my explicit permission. It is entirely my own work. I will be trying to update and work on this periodically until it is complete.

Mini-Z pcb work checklist: Fellow racers MR-03

Yes No

Board power “on” upon receipt (binds)?  
Steering Functions properly upon receipt:  
Centers and recenters properly?  
Left + right turn functions properly?  

Throttle functions properly upon receipt:
Forward?  
Reverse?  
Brake?  

Throttle FET installation: 2x2 (Fairchild 8858)
Check for circuit continuance from top of FET legs?  
Check for bridging of connections in FET circuits?  
Using test cells, board powers “on”?  
Steering functions properly?  
Throttle functions properly?  
FET stress test:
Forward mod motor with resistance test pass?  
Reverse mod motor with resistance test pass?  
Brake functional?  

Customers car is now Awesome?  

Action B
2011.05.06, 07:30 AM
reserved for update (if this is not okay mods please delete)

dr_hfuhuhurr
2011.05.09, 03:36 PM
Just got my FET's done by Action B last week. WOW, what a difference. The car was completely different. His service was fast, clean and complete. The testing sheet was a nice touch.

Thanks again!
Blake

arch2b
2011.07.12, 02:58 PM
just a suggestion but with the new kyosho stock and kyosho cup class racing, i would stock up on stock pcb fets as these are going to be the only race legal replacements for when fets fry. it's not a matter of if, but when.

do you happen to have a list of pcb numbers and corresponding fets?