Mark, I am just pointing out we can be so afraid of death we go crazy and can't live our lives, only exist.
Instead, be aware of the danger, have a clear head, and follow all safety procedures and precautions. As you would for anything dangerous, like driving a lethal weapon, aka vehicle.
Instead, be aware of the danger, have a clear head, and follow all safety procedures and precautions. As you would for anything dangerous, like driving a lethal weapon, aka vehicle.
If there is no risk of arc flash, the risk of injury from electric current is relatively low - it's far more dangerous when the electricity can come and get you - no contact required as like when working in switchgear.
Thankfully, this is not encountered in a tube amp, and as long as someone takes general safety precautions, they will be fine - even if they DO get a shock.
No need for a rubber mat to stand on - buy safety shoes.
Any footwear with these logos will be certified to insulate you.
Some people die from drinking water in any given year - in other words, anything can be dangerous in the right situation.
FWIW, I've gotten many shocks in my life and I'm still here. The most unpleasant was 950VDC from an oscilloscope (that's the day I realised the heater in a focus tube is only 1V but it's sitting at 950VDC above chassis ground - about 20 years ago) even thought the highest voltage was closer to 50kV, it was current limited (ignition coil in a car). That shock was from my hands to my knees (used my kneews to brace myself against the car which had a wet chrome bumper while adjusting timing and the car had wires with cracked insulation).
Now, every amplifier I build has up to 700VDC inside and I'm pleased to say it's been a long time since I got a shock. The last time was just from carelessness - I picked up a 100nF cap that had 400VDC in it by the leads after having just disconnecting it from a test circuit! Oops. So what? LOL We used to charge up small caps like that and throw they to friends saying "Here! Catch!".
I once had a friend of a friend shock me with the head of a hammer that he had but charged up with a Van De Graaff generator, too. I could have swung for him lol.
Thankfully, this is not encountered in a tube amp, and as long as someone takes general safety precautions, they will be fine - even if they DO get a shock.
No need for a rubber mat to stand on - buy safety shoes.
Any footwear with these logos will be certified to insulate you.
Some people die from drinking water in any given year - in other words, anything can be dangerous in the right situation.
FWIW, I've gotten many shocks in my life and I'm still here. The most unpleasant was 950VDC from an oscilloscope (that's the day I realised the heater in a focus tube is only 1V but it's sitting at 950VDC above chassis ground - about 20 years ago) even thought the highest voltage was closer to 50kV, it was current limited (ignition coil in a car). That shock was from my hands to my knees (used my kneews to brace myself against the car which had a wet chrome bumper while adjusting timing and the car had wires with cracked insulation).
Now, every amplifier I build has up to 700VDC inside and I'm pleased to say it's been a long time since I got a shock. The last time was just from carelessness - I picked up a 100nF cap that had 400VDC in it by the leads after having just disconnecting it from a test circuit! Oops. So what? LOL We used to charge up small caps like that and throw they to friends saying "Here! Catch!".
I once had a friend of a friend shock me with the head of a hammer that he had but charged up with a Van De Graaff generator, too. I could have swung for him lol.
Okay, thank you for clarifying. 😀
I get more use out of a rubber mat... Unless has to have a certification too.
Curious, what makes this any different than the rubber soled house shoes I wear at home?
Another way of saying what I said. 😉
Ouch, well, guess one way to find out about oscilloscope voltage.
As for ignition coils, I have to, testing for spark. Also, my great uncle to teach his daughters about electricity made what we called the shocking machine, though could switch it to light a Christmas bulb too (with a brass throw with a Backlight knob). It used a generator from a hand crank telephone and two brass bits to hold on. My sister is still upset about shocking her... Dad when he wasn't in his right mind, took it from me, and gave to a cousin. One of these days find another generator and build one for my nieces and nephews.
In auto shop, there was an ignition circuit in the classroom and students compete to see who could hold on the longest (I never been competitive and had plenty else to do, so didn't). There was this very stout, wide, tall, and basically all muscle football player. He held onto the leads the whole 55 minute class and showed no signs of discomfort, he was bummed he had to go to the next class. 😆 I had forgotten about that, odd how the mind remembers the most random stuff.
🤣
Well Richard (@OldHector ) looked into those transformers, good bit less cost than a standard transformer, significantly less cost and complications then the way I had planned. 😳 Only thing is no 230VAC, closest is 270VAC. So, using an online calculator, says 210Ω drop it down, so put that into PSUD and got 325VDC (300VDC specified) out of the bridge rectifier, plus an interesting result: voltage ramps up taking about a half second to be at full voltage. Neat! Also, the ripple goes way down. Super neat!
Possible lawsuits... Safety footwear is certified, those Jordan 5's aren't 🙂
For the record - these work fine to insulate me -- I found that out when I brushed the probes of my voltmeter and it beeped... I was sitting there connected to B+ for a while with no clue whatsoever until the VM beeped and showed 300 odd volts 🙂
I will say I agree that a concrete floor conducts more than I ever thought.
I was laying under my car working on it. Broke a light bulb (but it was LED so it kept working) which made contact with the jack and therefore the car... Laying on my back on the floor, I found out the car was at 120VAC when I got an anger inducing shock. That light disintegrated when I whipped it at the wall.
Also, piѕѕing away how many Watts with a 210R resistor will make lots of waste heat - use a BIG resistor (20W or so) or just modify the circuit for the higher voltage - the tubes can take it.
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I don't own any shoes suitable for sports, don't play any. When in public wear dress shoes or dress boots, been that way since early in High School (I didn't care what others thought). My house shoes are the most casual shoe I own.
🤣
Well, been a frigid week, high in the low 50s, house is a brisk 70 degrees (wearing an undershirt, turtleneck shirt, a thick jumper, and still a little brisk) so no flip flops here.
These are my house shoes, very old and desperately need polish, my other footwear get kept nice. They are what I wear when working on vehicles, thankfully oil wipes right off.
My house is ~ 26°C at the moment... These slides are just my slippers effectively 🙂
Most people who buy Jordan's don't wear them for sports - they are decorative / status symbol - my other half wants a pair that just came out.
Only 300$
I have one pair of dress shoes - I bought them for a wedding 10 years ago at a thrift shop for 10$. 😛
Most people who buy Jordan's don't wear them for sports - they are decorative / status symbol - my other half wants a pair that just came out.
Only 300$
I have one pair of dress shoes - I bought them for a wedding 10 years ago at a thrift shop for 10$. 😛
I never paid special attention to special shoes, rubber mats, etc. I do have a rubber mat at the kitchen sink, and at my woodworking bench however. Way easier on the joints in my legs these days.
I am however in the habit of using only one hand when working in a live circuit, wether turning adjustment knobs, probing with a meter, etc. A handy trick is to use several multimeters, have one with clip leads attached to the main supply voltage as your main indicator, and a second with one lead clipped to your ground or "zero" rail. That way you can safely poke around with the other meter lead to get your measurements without shuffling around. Write notes as you go, power down the amplifier, and check that the voltage has gone down on the first meter. Then use the second to take a few quick measurements to ensure the coast is clear. Then you can make any necessary changes and power it back up for another round of testing if needed.
Ever since I adopted this method I haven't gotten shocked in years, and it helps you to slow down and be methodical about things.
I am however in the habit of using only one hand when working in a live circuit, wether turning adjustment knobs, probing with a meter, etc. A handy trick is to use several multimeters, have one with clip leads attached to the main supply voltage as your main indicator, and a second with one lead clipped to your ground or "zero" rail. That way you can safely poke around with the other meter lead to get your measurements without shuffling around. Write notes as you go, power down the amplifier, and check that the voltage has gone down on the first meter. Then use the second to take a few quick measurements to ensure the coast is clear. Then you can make any necessary changes and power it back up for another round of testing if needed.
Ever since I adopted this method I haven't gotten shocked in years, and it helps you to slow down and be methodical about things.
I tried that, then too warm to sleep. Weird, huh?
Maybe because I grew up without central cooling (none at all, inside get to 35*C in summer) and no central heat. On heat, it was a wall unit in the dining room and the back of the house, only turned on once too cold with a layer on (Oma's family is mostly Dutch ancestry, super frugal).
House shoes is the same as slippers to me.
Oh dear...
🤣
I found wearing knitwear in 46*C summer weather causes some folks discomfort so I wear a sport coat and no one is the wiser that I run a tad cold. I just can't stomach sport shoes with dress clothes. 😛 Plus, I was raised to dress nice for church, though now you can almost be naked and in rags to church.
Hey @Lingwendil
Like this? LMAO
Also for those in Canada - Mastercraft meters from Canadian Tire are a good value and more than accurate enough for amplifiers... Don't set it to ohms and try to measure B+ in a tube amp though. That yellow meter (not from Canadian Tire) now reads 1.1kohm instead of open.
Like this? LMAO
Also for those in Canada - Mastercraft meters from Canadian Tire are a good value and more than accurate enough for amplifiers... Don't set it to ohms and try to measure B+ in a tube amp though. That yellow meter (not from Canadian Tire) now reads 1.1kohm instead of open.
What ever is going on with my body is driving me crazy. Think finally getting over what ever it is, then last night took a turn for the worse, feel absolutely terrible. But, I was so looking forward to using the program, so opened the cable package and darn it, dyslexia strikes, got a male instead of a female. More money flushed down the toilet, yay. Why do most things have to be a multi day fight to do a simple task? (Rhetorical question.)
I make a modular amplifier that actually might make things easier on you...
Proven design, off the shelf parts. No expensive/exotic tubes/parts, either.
Can choose from over 100 output tubes for it, too - but I would stick with TV Sweep tubes as triodes.
Have a look and see if it might suit you. You can make monoblocs, but it'll cost more since you then need two power supplies, two chassis, two biasing systems etc.
https://www.diyaudio.com/community/threads/modular-amplifier-1.375206/
Proven design, off the shelf parts. No expensive/exotic tubes/parts, either.
Can choose from over 100 output tubes for it, too - but I would stick with TV Sweep tubes as triodes.
Have a look and see if it might suit you. You can make monoblocs, but it'll cost more since you then need two power supplies, two chassis, two biasing systems etc.
https://www.diyaudio.com/community/threads/modular-amplifier-1.375206/
Curious, how is something designed for many specifications at the correct specification for any? I been told and makes logical sense an amplifier designed for multiple tubes isn't nearly as good as one designed for one.
Thanks. 🙂 Are you offering assistance?
Topology. The circuits can be universal with only small changes needed such as biasing and load resistors.
A lot of the tubes in the list are very similar with the main difference being pinout, tube base, plate cap or not etc. 12AV5GA is octal, 12GT5 is Noval, and 12GE5 is compactron. All are the same tube with different pinouts and sockets.
Other tubes might need a different output transformer impedance. 12AV5 etc will work into 2k2 load and be happy while typical audio tubes like KT88 want more liek 5k.
I wouldn't use audio tubes for the outputs myself - I find sweeps a better value and they make a lot of power as triodes where typical audio tubes don't.
A lot of the tubes in the list are very similar with the main difference being pinout, tube base, plate cap or not etc. 12AV5GA is octal, 12GT5 is Noval, and 12GE5 is compactron. All are the same tube with different pinouts and sockets.
Other tubes might need a different output transformer impedance. 12AV5 etc will work into 2k2 load and be happy while typical audio tubes like KT88 want more liek 5k.
I wouldn't use audio tubes for the outputs myself - I find sweeps a better value and they make a lot of power as triodes where typical audio tubes don't.
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Adriel, it might make sense to take a closer look at what kodabmx has to offer. Looks more like a kit to me, maybe with some possible support help. OTOH if you want to build something from nothing more than a schematic then there is a lot more to learn if you want to get it right.
Thank you for indulging my curiosity. 🙂
Well, this is well and good, however, without your assistance, and a lesser degree a BOM, I am in the same place as I am now, nay be worse as have to spend hours and hours doing another BOM. I understand not being able to assist, no hard feelings.
I don't mind assisting people. I made the designs open source.
I can also provide the parts for them. As of right now I also have some boards already built up.
I don't provide a kit, per se. Transformers and chassis are heavy and so cheaper to buy from the usual channels. Chassis jacks, wire, pots, switches etc are a personal touch.
I use the Triad VPT12-8330 for output. You would need two per channel. Arrow has them for 34$CAD, Digi-key wants almost twice that. https://www.arrow.com/en/products/vpt12-8330/triad-magnetics These suit most triode connected sweep tubes.
Power transformer is easy because I designed it to use an isolation transformer. 120V into the PSU board. Triad VPT230-1090 or similar. https://www.digikey.ca/en/products/detail/triad-magnetics/VPT230-1090/2090090
Heater power is up you but I use "12V 13A power supply" https://www.aliexpress.com/item/1005003973467473.html
It's not a Heathkit, but it's probably a lot easier place to start from - It's a lot easier to make wiring mistakes with point to point 🙂 Of course the third option is to just buy a built prototype and since I have too many amps the price won't be very high, but I have a feeling the shipping would be horrifying, and you probably want to built it yourself 🙂
I can also provide the parts for them. As of right now I also have some boards already built up.
I don't provide a kit, per se. Transformers and chassis are heavy and so cheaper to buy from the usual channels. Chassis jacks, wire, pots, switches etc are a personal touch.
I use the Triad VPT12-8330 for output. You would need two per channel. Arrow has them for 34$CAD, Digi-key wants almost twice that. https://www.arrow.com/en/products/vpt12-8330/triad-magnetics These suit most triode connected sweep tubes.
Power transformer is easy because I designed it to use an isolation transformer. 120V into the PSU board. Triad VPT230-1090 or similar. https://www.digikey.ca/en/products/detail/triad-magnetics/VPT230-1090/2090090
Heater power is up you but I use "12V 13A power supply" https://www.aliexpress.com/item/1005003973467473.html
It's not a Heathkit, but it's probably a lot easier place to start from - It's a lot easier to make wiring mistakes with point to point 🙂 Of course the third option is to just buy a built prototype and since I have too many amps the price won't be very high, but I have a feeling the shipping would be horrifying, and you probably want to built it yourself 🙂
I did look and no data on the sound, though was willing with assistance. The other concern is this be worse as these are not designed for one OPT, instead any, so I would have to acquire and learn how to use an oscilloscope. The L1 clone has the advantage of the feedback loop being correct or almost correct.