I got this Silvertone 1448 Guitar/Case/Amp combo for a good price at the pawn shop. My wife wanted it as an antique-decoration-thing for the library. Who was I to argue about the wife wanting me to buy another guitar and amp? My first internet searching, just to find out what it was worth and what to offer, pointed out the well-known safety issues with it. It was designed with a tube-set used in old budget radios, with a voltage that roughly added up to 120v, and did not have a power transformer. It also had a non-polarized two-prong plug, so, depending on how you plugged it in, the chassis/ground was either direct wired to hot or to neutral. I tested it when we first got it home, and, after rearranging the tubes to their proper slots (and replacing the 12v preamp tube that burned out, I'm guessing, from being in the 35v rectifier tube slot while powered on), and cleaning the volume pot, it worked. I'm guessing most folks either put up with the safety issue and left them alone, or followed the common advice to take them to an experienced amp tech, so the update schematic wasn't available anywhere. I have very little experience with electricity beyond some wiring in my house/machinery and replacing a couple broken components with exact matches on other electronics in the past, but I really wanted to use this as a toe-in-the-water for working on amps, and figure out how to do it myself. There was plenty of mention on the interwebs that it needs an isolation transformer and 3-prong plug added, but I couldn't find a schematic for performing the update that matched the schematic of this specific amp (or any of the many models that exactly match it). There was also mention that this sort of amp would have a "death cap", but none of the schematics that pointed out where a "death cap" could be found matched what I saw on this amp's schematic. I didn't want to start with a "show me how to fix this"-type thread anywhere, since most of those I see end up with "if you have to ask, you don't need to know"-type responses. Also, I figured I'd learn more if I had to do some leg-work and figure out how to adapt the tribal knowledge to my specific application. I figured out what I could regarding sizing and selecting the isolation transformer, and got one ordered. When I got it, I didn't like any of the mounting possibilities inside the case, so I decided to mount it remotely in a power cord brick. I gathered that having the primary of a transformer before the on/off switch was poor form, because it would continue to draw power when plugged in and 'off'. So, I put a switch on the power brick, and added another fuse to get it on the hot line as early in the circuit as possible. I also gained an understanding of the problem with a "death cap", why they were used, and why they could be removed once an amp was properly grounded. This amp did not have a ground switch (you just had to reverse the plug if it was buzzy, I guess), but I did find one place (C3) where the only thing between hot line and ground was a capacitor (0.05uf / 600v). After I had everything wired up and proven still-working, I clipped out C3, and it still worked, so I think it was the correct one and no longer served a purpose with the proper grounding installed. I've got about an hour play-time on it, and have had it plugged in, but powered off, for as long as 6 hours. The transformer is not any warmer than room temperature, and the amp sounds surprisingly good for its size and speaker. The 50c5 power tube is uncomfortably hot to the touch, but I gather this is normal for this tube/circuit. I'd appreciate it if someone who actually understands amps/electronics would compare the before/after schematics and tell me if they see anything I did wrong, or still need to do. I think it's right, but I'd like someone with experience to critique it. The first picture is the original schematic. The second is my revised schematic. The third is the actual wiring. I took it before I removed C3 (the one directly above the red tube electrolytic), but with the new filter cap in place. Thanks in advance.