New ham, Ubitx issues #ubitx

dwhacks
 

Well after many years of wanting to do it I finally took the test and passed with 87/100 questions! That gives me Basic with Honours up here in Canada, which means I have access to all bands.

Of course, now after being issued my callsign today while I was at work I was eager to get on the air, and finally try out the transmit on my ubitx (I've been listening for a while now). To make a long story short, I've messed something up. I think I may have blew the finals (IRF510) on my V4 board by running an unmatched antenna (like I forgot to tune it, and tried FT8). I touched the heatsinks with my fingers after a few cq calls on FT8, the first one (closest to the power plug) was cold, not warm at all, and the second one (closest to the antenna jack) was cooking hot! too hot to put my finger on! So I attached a dummy load and wired in my meter to check how much amps it was pulling, and I got 1.3A without speaking into the MIC just on key down. Idle is around 370mA which is about right seeing as I have the nextion display and second arduino board.

I don't have any spare IRF510's, and I've read that the IRF520's I have wont work, but I would like to be sure this is the problem before I swap them out. To troubleshoot I tried swapping the IRF510s on the board thinking that now maybe the one closer to the power input plug would get hot, but this wasn't the case, the one closer to the antenna still got hot. Is this bad finals? or is there something else I should look at also.

Thanks!
Dayne
VE7DNT

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