Salvage a microwave oven transformer and remove the HV secondary.
Wind your own high amperage low voltage secondary to the specs your need
/ work.
The web will have many sites that show how to do this for resistance
welding batteries etc.
Hugh
SRY wrote:
>I've been meaning to build a resistance solder unit. I went to the
>local RS yesterday to see what types of transformers they had. They
>didn't have anything close to what I hoped to find. Not deterred I
>went to an electronics store. There sure were a number of large flat
>screen tvs in for repair! I gave the tech what I hoped would be an
>easy part to provide. Nope, he said, try Jameco on line. So I came
>home and I did. Either I'm not sure what to put in the filter or I'm
>looking for an oddity.
>
>I'm trying to build a resistance solder unit.
>
>I've searched on-line.
>
>For the curious here are a couple of links:
>
>http://www.girr.org/girr/tips/tips1/solderer.pdf
>
>But this one uses a battery charger. I was hoping for something a bit
>smaller and more home-brew.
>
>This is more like what I was hoping to find but a bit pricey:
>
>http://www.istnet.net.au/~wamrc/res_solder/index.html
>
>
>Yeah, I also went out to the Train Index. I have the Mainline Modeler
>magazine. That's what started this train of thought.
>
>And there is this reference too:
>http://www.trainweb.org/bristol-s-gauge/Projects/rsu.html
>
>So what the heck am I looking for???
>
>I thought I knew!
>
>One article suggests a transformer that takes house current and on the
>secondary posts gives 6-8 volts AC at 3 Amps. That's what I was asking
>for at the local stores.
>
>Another articles says I need a filament transformer that provides less
>than 7 volts at 6 or more AMPS.
>
>So far no luck. Any help appreciated.
>
>Gordon
>
>
>
>
>Be sure to visit the group home and check for new Links, Files, and Photos:
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>
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>Yahoo! Groups Links
>
>
>
>
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>