Mutchus

Among the many smaller jobs that have to be done to this vintage Hofner Colorama II is to flatten the warped plastic pickguard and rear tremolo cover. Here’s how they both looked before starting: Pickguard: Rear tremolo cover: I decided to tackle the rear tremolo cover first, since it appeared to be a much simpler job and also easier to replace should things go horribly wrong. I really couldn’t find any information about this on the Internet, so I did what seemed logical in my head, which was to sandwich the plastic in-between two panes of tempered glass, clamp the whole lot together, and heat it with a very hot hairdryer. Here’s the setup: After 10 or 15 minutes of heating the area above AND BELOW the cover, I took the top pane of glass off to confirm that the plastic had become soft, then clamped everything back in place and left it to cool naturally. Since I wasn’t in a hurry, I left it for 24 hours, although I’m sure that wasn’t necessary at all. The tremolo cover came out complete...

A very simple solar charger circuit project can be designed using few external electronic parts . This simple solar charger circuit is capable of handling charge currents of up to 1A. Alternate component values are given in the figure for lower current applications. Circuit diagram:   Solar charger circuit project using transistors circuit diagram The only adjustment is the voltage trip point when the current is shunted through the transistor and load resistor. This should be set with a fully charged battery. As the transistor and R3 have the entire panel’s output across them when the battery is fully charged, all of the current from the panel will be going through R3 and the Darlington transistor TIP112, so these must be well heat sunk. Adjust R1 for the trip point, usually 14.4 V – 15 V for a 12 V SLA or a 12 V Ni-Cd battery.