Many CB and Amateur operators (Moleculo, for one) are replacing their hi-amperage linear power supplies with switching supplies because of their light weight , relatively small size. and lower cost per amp.
Mainframe computers have utilized high amp switching supplies for several years, and many of these supplies are now showing up on the surplus market. Last week, I purchased an HP mainframe supply from a surplus outlet in Medellin. This particular supply is rated at 12V-74Amps (110vac input) or 12V-106Amps (220vac input). The supply was "reconditioned": i.e. - cleaned, and run at maximum output (94 amp draw) for 12 hours. It measures 6"W x 4"H x 8"D, and weighs about 4 lbs. The cost was 49000 pesos (approx $22USD). Like PC supplies, this unit is "hot-pluggable", meaning it won't turn on unless it's connected to the mainframe. When I mentioned that I was going to use it to power some of my radio equipment, the store's tech showed me how to hot-wire it by connecting 3 pins on the plug together. He also showed me how to adjust the output voltage, and set it to 13.4vdc, which is the max the supply will do.
I tried it out today, and it easily powered my 5-pill TX600 to 800W peak with negligible (.15V) voltage drop.
The plan now is to build a housing with a voltmeter, ammeter, external voltage adjust control, and some high amp connectors. I also need to change the cooling fan to something quieter. I'll post some pics of the finished unit in a few weeks. 73s.
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Mainframe computers have utilized high amp switching supplies for several years, and many of these supplies are now showing up on the surplus market. Last week, I purchased an HP mainframe supply from a surplus outlet in Medellin. This particular supply is rated at 12V-74Amps (110vac input) or 12V-106Amps (220vac input). The supply was "reconditioned": i.e. - cleaned, and run at maximum output (94 amp draw) for 12 hours. It measures 6"W x 4"H x 8"D, and weighs about 4 lbs. The cost was 49000 pesos (approx $22USD). Like PC supplies, this unit is "hot-pluggable", meaning it won't turn on unless it's connected to the mainframe. When I mentioned that I was going to use it to power some of my radio equipment, the store's tech showed me how to hot-wire it by connecting 3 pins on the plug together. He also showed me how to adjust the output voltage, and set it to 13.4vdc, which is the max the supply will do.
I tried it out today, and it easily powered my 5-pill TX600 to 800W peak with negligible (.15V) voltage drop.
The plan now is to build a housing with a voltmeter, ammeter, external voltage adjust control, and some high amp connectors. I also need to change the cooling fan to something quieter. I'll post some pics of the finished unit in a few weeks. 73s.
- 399
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