Hi folks. Recently purchased this vintage alarm clock. Everything is working fine. My only gripe is that the bulb is not bright enough to view the time in a dark room. Before I venture into disassembling the clock, is this normal for this era? Do the bulbs get dimmer with time, or do they simply "burn out" completely. I even considered maybe using some aluminum foil near the existing bulb to diffuse the light. One last question... must you replace the original bulb with an exact duplicate, or are there modern, compatible bulbs available that are brighter?