[Skimmertalk] QS1R (Rev C) over heating?

[Dave]

My QS1R failed recently. The fault was the 1.2V supply, which is fed from
an L1117 1.2 regulator.

Running the 1.2V rail from an external supply showed a current draw around
300mA when listening to a broadcast station with SDRMAX V software, but
around double that current when running 7 slices with CW Skimmer.

The original regulator, which uses the PCB as a heatsink, seems inadequate
for the current needed by the Cyclone III FPGA. I tried an LM317 (TO220)
regulator with a small heatsink, however the heatsink reaches over 90C
running 7 x slices with Skimmer.

Before I bolt the regulator to the case, has anyone  checked their QS1R for
boiling hot regulators, modified theirs, or has mine an overheating fault?
By the way, Skimmer works with multiple slices, as does the QS1R when used
to listen “single channel” as in broadcast station listening.

Thanks
Dave G4AON
-- 
Sent from my iPhone SE
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