Mosfet mod for early Ranger 2950DX?

[seedkey]

they are not the same device. take any radio that comes factory with the 520 and substitute the 520 with the 2030. in other words, remove the 520's and replace with 2030's. then look at the output with a scope. you will see the 2030 is not stable in a circuit designed for the 520 (especially at low power). many times it will get by in an am/fm only radio, but we have always had problems with an ssb capable radio that comes standard with the 520.

I have done just that and i see no difference in power output just minor the differences that you would see like when you change a 2sc1969 bipolar transistor.
The IRF-520 is the same device as 2030. But there are different manufactors of the IRF-520 you have to get the International rectifier brand. This are the ones I use and find no difference are IRF510PBF-ND $1.75 each.
I also tried the cheap version IRF520V and they sucked and were all over the place , miller charge was high but also cost .50 cents I bought them because they were closing them out to go to RoHS.
International rectifier is what you want.

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=IRF520NPBF-ND

 

[ss8541]

I have done just that and i see no difference in power output just minor the differences that you would see like when you change a 2sc1969 bipolar transistor.
The IRF-520 is the same device as 2030. But there are different manufactors of the IRF-520 you have to get the International rectifier brand. This are the ones I use and find no difference are IRF510PBF-ND $1.75 each.
I also tried the cheap version IRF520V and they sucked and were all over the place , miller charge was high but also cost .50 cents I bought them because they were closing them out to go to RoHS.
International rectifier is what you want.

http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=IRF520NPBF-ND

those are the irf's we use....but that has nothing to do with replacing 520's with 2030's.

when we have dropped 2030's in circuits that were designed for the 520's we have had problems more times than not. with ssb capable radios we always had problems. you can't see it with a wattmeter if that is all you use, but use a scope and a spec-an, and you will see.

an example is the new mosfet galaxy 2517 that comes with 520's standard. if you blow your output and replace the 520's with the 2030, ssb is distorted and your low carrier power for am/fm is as well. we have done this more than once and got the same results on the spec-an and scope.