![]() CR907 is being replaced with a STTH2R06 ultra-fast rectifier. Also known compatible as some units shipped with them in. Crap by modern standards but cheap and with a higher voltage headroom and similar characteristics to the original device without being too daring. Pre-regulator exploded The pre-regulator MOSFET Q9070, an IRF710 exploded. I applied 43V across TP940/950 to bring the scope up on DC and it came up fine. After this explosion, I tested the pre-regulator mostly worked by applying 22V across C925 to see if the SMPS controller was still working. Took the driver transistor out and a diode. About 30 minutes after power up, the IRF710 in the preregulator blew it's arse out. ![]() A sticker will go on the back of the unit saying these need to be replaced in 10 years. I replaced the RIFAs with NEW Kemet RIFAs. Pretty good condition: First step I did was empty it of the ageing electrolytic capacitors and mains filter: New high quality Panasonic and Rubycon parts were substituted in. Decided to do a full refurb on it as these are known to be occasionally dodgy as hell. Powered it up, seemed ok bar a couple of issues. Described as working, which it mostly was for a bit so no complaints there. Bought a 2235 from a hamfest type event for a whopping £25. Thought I better break this off the TEA stuff so it's easier to find if anyone else comes across it.
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