[EMAIL PROTECTED] made an utterence to the drakelist gang ---------------------------------------------------------------------- To my knowledge, the same transformer and thus the same voltage was used on all L4B and L7 power supplies. Some diodes had equalizing resistors and/or capacitors across them. With later versions of the supplies, better quality control of the diodes, etc, some of these components were dropped.
It is generally a good idea to replace all the diodes with higher ratings, e.g. 1 KV at 3A. In addition, replacing that 5K 7 watt resistor on the underside of the supply is a good idea as well. When that resistor opens up, it puts high voltage across the ALC pot and takes it out. That pot hasn't been made in over 20 years and is unavailable. Hence, that resistor should be replaced with one of 20-30 watts to help guard against such a failure. It's a good idea to check the bleeder resistors as well. In the 8-10 supplies I've rebuilt, failure rate seems to be around 75%. To reduce heat related problems, I use two 220v muffin fans, that will start on 110v, by placing them on top of the power supply cage with a small, stick-on rubber foot (thin) under each corner. The fans are very quiet and reduce the internal temperature of the supply dramatically. 73s, Evan ---------------------------------------------------------------------- On Behalf of [EMAIL PROTECTED] Submissions: [EMAIL PROTECTED] Unsubscribe: [EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost: [EMAIL PROTECTED] - help in body of message Zerobeat Web Page: http://www.zerobeat.net Brought to you courtesy of TLCHost.net http://www.tlchost.net/ ----------------------------------------------------------------------
