MRF 477 replacement with IRF 520

Emelso · Post by **Emelso** » Monday 27th Oct 2008, 20:30

I got an old President Jackson (silver faceplate) with MRF 477 final, which has been banged

Is there any chance to replace/rebuild it with IRF 520 or similar FET?

Thanks!

http://www.youtube.com/user/TheDefpom · Post by **The Defpom** » Monday 27th Oct 2008, 21:33

You can probably replace it with a MRF455 instead,it will require different mounting, and some capacitor changes (as per the HR2510 / Lincoln mod), but I expect it would work, and I doubt the final would ever fail again.

Emelso · Post by **Emelso** » Tuesday 28th Oct 2008, 0:31

Hi Defpom, tnx for help! I know this mod, but MRF 455 is hard to get and expensive (by us). I saw some good mods for 2SC1969/2312, now I try to redesign it for the 477.

Warbird · Post by **Warbird** » Tuesday 28th Oct 2008, 9:52

Isn't there a mod around somewhere for the HR2510/HTX100 that replaces the 477 to 455 mod with a 1446? The IRF520s are not a pin for pin replacement for the 477 and you wind up with them "cross-legged".

timrim · Post by **timrim** » Tuesday 28th Oct 2008, 10:24

You can directly replace the 455 with the 1446, so do you just need the mod? I may have a Lincoln here somewhere that has a 455 in it.

Emelso · Post by **Emelso** » Wednesday 29th Oct 2008, 4:40

I know the mod with MRF 455, as I wrote it before. I just need a cheap solution for the final.

warhorse · Post by **warhorse** » Thursday 30th Oct 2008, 6:39

Hi, this pre rogerbird mod works well'' uses sd 1446. this download site is currently ok.3 pics show the mod (ziped)virus free.

http://rapidshare.com/files/12584867...Mod__.zip.html

warhorse · Post by **warhorse** » Thursday 30th Oct 2008, 6:54

http://rapidshare.com/files/125848670/H ... _.zip.html

2nd time lucky..

KC7NOA · Post by **KC7NOA** » Tuesday 15th Nov 2011, 18:35

warhorse wrote:http://rapidshare.com/files/125848670/H ... _.zip.html

2nd time lucky..

Long gone .... still somewhere??

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