It's a 5-pin component in a radio car power supply (looks to be switching), and it looks like this:

The information was filed off by the manufacturer, although a few characters remain.

I've made a decent (but not entirely sure if correct) schematic of the entire power supply too:
.
TO-220 package implies a power device, either a regulator or transistor. 5 pins suggests something a bit more intricate than a single big power device.

R2 and the pot connected to an output suggests feedback, and inductors are suggestive of a switching regulator. It's clearly not a buck or boost converter since those use only one inductor (and the output here is lower than input so a buck converter wouldn't make sense). The topology does match a SEPIC converter though, so it's probably a SEPIC controller with integrated switching like (but not exactly) a LT1170.
I think it's a LM2575T; I'm taking a closer look at the device right now to see if any other markings survived.

[edit] The photos are in. processed with various methods before and after doing a highlight-then-wipe:


The markings precisely match up, including the bottom row saying -5.0 P+ as would be expected.
Look closely at the image in the second row, second column, and see that it reads '-ADJ' on the third row instead of '-5.0'. This means the output voltage is adjustable, not fixed at a particular voltage. The LM2575 is available in -3.3, -5.0, -12, -15, and -ADJ variants, and the fixed-voltage ones do not provide the 6V the radio is looking for (it cannot operate below 5.4V). I've found what could be the exact part used, after a lot of google-image-fu.
I somehow managed to find this picture:


So that answers that, and confirms I had found the (almost) right component. LM2576T is the actual component.
Where'd you get those expensive microscopes from? Shock
After doing some power testing, I found the radio pulls somewhere around 5A continuous / 7A peak when transmitting at full power ([edit] the high amounts of RF appear to fudge my multimeter's readings, I should use a dummy load for this instead of actually transmitting. I will do more detailed testing after I wake up to a freshly charged battery pack, as I expect around 2A transmit high power). This is well above the rating for the LM2576T of 3A; no wonder that component is fried.

oldmud0 wrote:
Where'd you get those expensive microscopes from? Shock

I actually use this lens. At closest focus, it can resolve really tiny details.
Thanks for those details, and good luck putting together a sufficiently-powerful supply for it. I suspect that your results may be rather useful to other people experimenting with SDR.
  
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