Here is a start: http://www.stancor.com/pdfs/Catalog_2006/Pg_038_39.pdf
and Line Transformers - Hammond Mfg. and Medical Grade Isolation Power Transformers On Triad Magnetics
However I would look on eBay for something used. Lots of options. Cheap but the shipping is as expensive as the transformer.
For bringing up a new amp with a power transformer I would be shopping for a Variac.
and Line Transformers - Hammond Mfg. and Medical Grade Isolation Power Transformers On Triad Magnetics
However I would look on eBay for something used. Lots of options. Cheap but the shipping is as expensive as the transformer.
For bringing up a new amp with a power transformer I would be shopping for a Variac.
The amp can be found here: tubes4hifi amplifier KITs page
It is basically a Dynaco ST-70 with larger transformers, a better input stage, etc. It comes with 2 conductor power cord.
I built it from a kit.
Everything works just fine - no blown fuses, noises, etc.
I've been using it for more than a year and it occurred to me, I have no idea if its delivering 60 watts, levels of distortion, etc. Basically, I want to learn something.
I've been scouring Ebay and craigslist looking at isolation transformer options.
I have the following:
Variac
Oscilloscope
Function generator
Couple digital multimeters
4 & 8 ohm 100 watt dummy loads
In my area code requires all electrical be run in conduit.
All outlets are properly wired with earth ground.
Correct me if I am wrong, I only need to isolate my oscilloscope from becoming the path to ground for equipment under test - I do not need to power the amp from an isolation transformer? If that is the case then I can score one for well under $100.
Basically, I have the heebee-jeebees that I may blow up my scope. If I do that my wife will kill me, she bought it for me a few months ago.
It is basically a Dynaco ST-70 with larger transformers, a better input stage, etc. It comes with 2 conductor power cord.
I built it from a kit.
Everything works just fine - no blown fuses, noises, etc.
I've been using it for more than a year and it occurred to me, I have no idea if its delivering 60 watts, levels of distortion, etc. Basically, I want to learn something.
I've been scouring Ebay and craigslist looking at isolation transformer options.
I have the following:
Variac
Oscilloscope
Function generator
Couple digital multimeters
4 & 8 ohm 100 watt dummy loads
In my area code requires all electrical be run in conduit.
All outlets are properly wired with earth ground.
Correct me if I am wrong, I only need to isolate my oscilloscope from becoming the path to ground for equipment under test - I do not need to power the amp from an isolation transformer? If that is the case then I can score one for well under $100.
Basically, I have the heebee-jeebees that I may blow up my scope. If I do that my wife will kill me, she bought it for me a few months ago.
Do you have a schematic of the mains input section of the amp, and a specification for the power transformer? I couldn't easily locate that on your link. It appears that the kit would not pass safety requirements in some countries if it was sold as consumer equipment, as it doesn't seem to state it has been appropriately tested and confirmed that it can be plugged in to the consumer AC mains.
If the power transformer, or your AC primary wiring were to touch or break through insulation and get to the amp chassis or any secondary side circuitry then you have AC mains on your chassis and speakers. If you touch a live chassis then you become part of a circuit to earth that may exist. If you connect any widget to the amp circuit/chassis then that may also become live and conduct current to earth if it had electrical connection to earth.
If I had such an amp on my bench then I would firstly inspect for clearances, and do a 1kV megger test from primary to chassis, and then put in a fixed wire protective earth to any test equipment, and probably a redundant protective earth in to a mains socket (assuming you have modern unadulterated mains distribution in your abode).
If the mains accidently connected through to your amp circuitry, then there would be two fault current paths it could take (to your test equipment chassis and then back to mains earth, and to mains earth in a separate socket).
I would suggest that 'earthing' everything is safer than 'floating' everything (as per using an isolation transformer).
If the power transformer, or your AC primary wiring were to touch or break through insulation and get to the amp chassis or any secondary side circuitry then you have AC mains on your chassis and speakers. If you touch a live chassis then you become part of a circuit to earth that may exist. If you connect any widget to the amp circuit/chassis then that may also become live and conduct current to earth if it had electrical connection to earth.
If I had such an amp on my bench then I would firstly inspect for clearances, and do a 1kV megger test from primary to chassis, and then put in a fixed wire protective earth to any test equipment, and probably a redundant protective earth in to a mains socket (assuming you have modern unadulterated mains distribution in your abode).
If the mains accidently connected through to your amp circuitry, then there would be two fault current paths it could take (to your test equipment chassis and then back to mains earth, and to mains earth in a separate socket).
I would suggest that 'earthing' everything is safer than 'floating' everything (as per using an isolation transformer).
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