Galaxy DX 949 Final and Driver question

[8113 Northern MN]

Ok my previous post I was asking about why no possible dead key. We went through and through the radio and again checked the voltages according to spec on the final and driver and found them to be way off. Assuming that was the culprit I ordered two new ones. However, instead of sending me the IRF520s I asked for the company sent me IRF540s. Can these be installed anyway? If so do i need to upgrade the circuitry in anyway? If so is there a diagram anywhere someone could point me too?

 

[ExitThirteen]

IRF540's will not work properly in a 949. You'll have to get IRF520's.



~Cheers~

 

[8113 Northern MN]

By not work properly can you explain? From my understanding the only difference between the two is one is a 10amp drain and one is a 30amp. Is there a work around to make it work. If one was to put it in the radio would it just NOT work or what would happen?

 

[ExitThirteen]

You'd get low output, and they will run hot. You'd have to modify the TX section of the radio to accommodate them, and at that, you won't get full output, as these will require higher drive to excite them to full output.


They aren't a drop-in. Sorry!


~Cheers~

 

[8113 Northern MN]

Thanks for the info. Ok, im trying to find the same pieces or buyer that i got these from and looks like he doesnt have any IRF520s left. All i am able to find now are IRF520 TO-220. Are these the same that the radio needs or something different?

 

[GnG8d]

The TO220 designation is just the package. I bought some 520's a few years ago at Mouser, they were so cheap I think I bought 50 just to make the shipping seem more reasonable. They are still around here somewhere.

 

[8113 Northern MN]

Thank you. I hate asking questions like that but did some google searching and was unable to find anything regarding the TO-220 part. Wanted to make sure the right part came this time