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I`m always on the look out for good equipment on the use market but even use, the Flukes are expensive.
 

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Discussion Starter #25
If you're looking for something to build, consider an analog plate-current monitor. I built this to monitor plate-current of single or dual output pentodes, dedicated to octal tube bases: 7AC and 8ET, a good chunk of NA output tubes. It is hard-wired for 0 to 100mADC. I could have used a dual meter concept however, I went with the dual-muliplex mode, the ole slide-switch route. I am in the process of adding a modified LED module for dark settings...for those long sessions when you what to watch some TV at night and just set your amp under test in the corner, in glimpsing range of the meter...for those intermittent or reliability issues - or you could spark-up a bowl lay back and just watch that meter. Don't get couch-locked though...you may not move if the meter starts pegging. Ip meter.JPG
 

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Discussion Starter #26
Built a new load box today, 8 ohm resistive...rated 100W (2 paralleled, 16 ohm resistors). I can now test higher-powered amps for extended periods of time. I have been considering an active load and it will require further research into the emulation...anybody have some tips?

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Built a new load box today, 8 ohm resistive...rated 100W (2 paralleled, 16 ohm resistors). I can now test higher-powered amps for extended periods of time. I have been considering an active load and it will require further research into the emulation...anybody have some tips?

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Looks "COOL" in every regard! Congrats!
 

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Discussion Starter #29
Can I ask why the fuse ?
I added that as a series component, I have a fixed value L-pad that I use with the load box for 200W testing. I will sometimes install a fast-blo fuse in the holder...mainly testing for transients during certain test conditions. The fast-blo fuse will be more sensitive to a transient response...a slow blo may not fuse enough to open. Even though I have a scope, it is not smart...no delayed trigger and no memory so, I cannot track and hold a high frequency transient...one thing for sure, sometimes I do miss the calibre of equipment when and where I worked...you make do with what you got and sometimes you get creative.
 

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Discussion Starter #32
finally a use for that drawer full of old CPU fans I saved!!
I get those odd ball feelings sometimes a lot, kind a of a gut feeling...do I keep it or do I turf it? If it's small I keep it...end up with a pile of storage cabinets. I have my wife keep most containers for that very reason...I may be a pack-rat for certain things, it's almost like a security blanket.
 

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Here's the other one that I built. An 8.87 ohms, 50W resistor mounted to a 45W CPU cooler. The camera freeze-framed (The J. Geils Band) the fan which is on during this shot. The power to the fan is provided by a 12VDC wall wart.

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I'm guessing that while using that, you'd be monitoring output on a scope to confirm that things are happening? I've got 4 of those same resistors in 10 ohm. Been thinking of making a dummy load for a while now. Be nice to have a watt meter inline.
 

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Discussion Starter #35
I'm guessing that while using that, you'd be monitoring output on a scope to confirm that things are happening? I've got 4 of those same resistors in 10 ohm. Been thinking of making a dummy load for a while now. Be nice to have a watt meter inline.
That's my main problem. I should be using a storage scope so, that I can freeze the trace and store it for study...transients occur too quickly for my eyes to catch it...if the fuse blows, it may lead me to believe that a transient is occurring. One of these days I will probably take the plunge and buy one...I'm the same way with most things...sometimes wait to long to pull the trigger.
 

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Here's some more test equipment I have. The power supply has been modified a bit. I use it for zapping shorted scanners and percussion circuits in Hammond tonewheel organs.
 

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Very nice Tube testers...those models are commanding high value now. The modern types are so complex now but I think yours have a cooler look.
I got both of them when I bought the assets of a tube amp tech who passed away here in town. I use the Stark most often as it's easier to set up....That said, for tubes I plan on selling, I use the Hickok.
 
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