The measurements you see on my website are done with the board sitting on the lab bench. The only parameter I can see improve when moving the amp to a chassis is the mains hum (which is already extremely low on the bench). I'd expect the EMI/RFI immunity to increase further with a metal chassis as well.
I do agree with the safety concerns expressed by others - both in terms of electrical safety and fire safety. That said, I regularly run my circuits as prototypes on a wooden shelf. Just keep pets, mini-humans, and curious fingers away and turn the amp off when you leave the room.
Tom
If you want the looks of a wood chassis with the EMI and safety benefits of a metal chassis, you could line the inside of it with copper foil and connect the foil to safety earth. You can get it in reasonably sized self-adhesive sheets of various thicknesses, and once the PCB standoffs etc. are screwed through it then it isn't going anywhere. If a fault develops that makes the chassis live then it's connected to earth via the foil and trips the breaker: no more fire risk than any other piece of wood furniture.
Thank you's.
I took inspiration from an audio brand that shall remain Naimless!
Shame I only see the oak front and heatsinks.....
1.5mm single strand mains cable, easy enough to work but stiff enough to retain it's shape.
Bent using a pair of straight circlip pliers which have round tapered arms providing a selection of bending radii.
I have also filed a slight flat where the arms meet so they treble up as long nose pliers.
There are many variants of circlip pliers !
I took inspiration from an audio brand that shall remain Naimless!
Shame I only see the oak front and heatsinks.....
1.5mm single strand mains cable, easy enough to work but stiff enough to retain it's shape.
Bent using a pair of straight circlip pliers which have round tapered arms providing a selection of bending radii.
An externally hosted image should be here but it was not working when we last tested it.
I have also filed a slight flat where the arms meet so they treble up as long nose pliers.
There are many variants of circlip pliers !
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I hear a lot of advice regarding insurance companies and I'm not naive enough to suggest that an opportunity to deny a claim isn't irresistible to some (although I've never had any issues with insurance companies; the few claims I've made were handled quite reasonably, but I don't buy insurance from the lowest bidder either), but I've never been able to actually find definitive evidence that a fire claim was denied because of a DIY audio device or the use of a non-UL/CSA listed electrical device (or one with a counterfeit UL/CSA label, which is common enough that there is a regular stream of recalls from Health Canada, whom issue all safety related recalls in Canada, for such products sourced in China and sold at major retailers).
If it's happened somewhere, you would think there would be public records of such, since the homeowner would surely take it to the courts.
Until I do, I consider it an urban myth.
Of course that is not a license to ignore common sense and established safety procedures, and to use the various standards that commercial products are expected to meet in order to obtain approvals as your guide in DIY construction.
RE: Copper foil
You can also buy copper sheet that is thick enough (say, 0.030") to withstand some heat, you would probably only need it in critical areas. A little 3M conductive spray adhesive or some solder and you should be OK. Mostly sold by craft and metal suppliers online.
RE: Pliers
Dental tools come in a variety of shapes (used to shape metal wire when wiring jaws shut due to injury) and are cheap on eBay. Stainless from India is generally good quality.
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You can buy round nose pliers at a tool supply store. I have a pair I've inherited from my grandfather.
There's an example of what I'm talking about:
Wiha 32750 ESD Prec Short Round Nose Pliers Made in Germany | Wiha Tools USA
Tom
There's an example of what I'm talking about:
Wiha 32750 ESD Prec Short Round Nose Pliers Made in Germany | Wiha Tools USA
Tom
Wiha Canada
Wiha Tools Canada
Nice stuff, but I prefer the India-made SS $6 orthodontist ones from eBay. A $10 tub of Plasti-Dip will provide plenty of material to be applied to the handles if you want.
No doubt the Germans make incredible tools, I have some Knoppix stuff that is outstanding, but you pay for it.
Wiha Tools Canada
Nice stuff, but I prefer the India-made SS $6 orthodontist ones from eBay. A $10 tub of Plasti-Dip will provide plenty of material to be applied to the handles if you want.
No doubt the Germans make incredible tools, I have some Knoppix stuff that is outstanding, but you pay for it.
I'm sort of with Tom, except for a couple of modifications (and noting my fave socket set is my facom one).
1. Jewellers screwdrivers get lost and trashed. New cheapish set every 12-18 months
2. For tools I'm not sure how often I will use I sometimes buy cheap and see if I break it. Then buy the good stuff
3. I cannot justify the cost of really good crimp tools
4. I generally look after tools but have killed a number of nice lindstrom cutters over the years. But a pair of those a decade isn't too bad
Then again recent bike repair ruined all my 8mm allen sockets (steel pedal thread into aluminium crank, add (mumble) wet salty winters. Ended up having to cut the pedal out mind. I really need a new hot spanner
1. Jewellers screwdrivers get lost and trashed. New cheapish set every 12-18 months
2. For tools I'm not sure how often I will use I sometimes buy cheap and see if I break it. Then buy the good stuff
3. I cannot justify the cost of really good crimp tools
4. I generally look after tools but have killed a number of nice lindstrom cutters over the years. But a pair of those a decade isn't too bad
Then again recent bike repair ruined all my 8mm allen sockets (steel pedal thread into aluminium crank, add (mumble) wet salty winters. Ended up having to cut the pedal out mind. I really need a new hot spanner
Or yearly... I went to college in Copenhagen. 6 km each way in all sorts of weather, including horizontal rain and salty snow. Thankfully, it was a straight and level road (not uphill both ways... ) I'd totally trash the chain and cables through the winter and just replace sprockets, chain, cables, and a few other sundry items once spring rolled around.
+1 for Lindström Tools. I've been drooling over their RX series of ESD-safe tools for years. Ergonomics matter - especially if you use tools more than just a few times a year.
Tom
) I'd totally trash the chain and cables through the winter and just replace sprockets, chain, cables, and a few other sundry items once spring rolled around.+1 for Lindström Tools. I've been drooling over their RX series of ESD-safe tools for years. Ergonomics matter - especially if you use tools more than just a few times a year.
Tom
180 pf capacitors
Hello Tom,
I have bought two of your modulus86 boards plus the power86 board. Mouser wants me to wait until July for some of the components. A couple of resistor values, the 180pf capacitors, the 1N4007-T diodes, the rectifier bridge and the heat sink and the Amphenol 3 Pole terminals.
I guess I can do without the terminals and use some other rectifier bridge, but what would be suitable substitutes for the other stuff?
Hello Tom,
I have bought two of your modulus86 boards plus the power86 board. Mouser wants me to wait until July for some of the components. A couple of resistor values, the 180pf capacitors, the 1N4007-T diodes, the rectifier bridge and the heat sink and the Amphenol 3 Pole terminals.
I guess I can do without the terminals and use some other rectifier bridge, but what would be suitable substitutes for the other stuff?