I'm a circuits/electronics noob, but I've already built a small (10w) amp and understand most of the basics. I'm going to be searching for a Toroidal transfomer which I saw a few last weekend. I'm going to be going here:
California Electronic & Industrial Supply (Great service, willing to help, great prices! and an awesome dog in the back! Located in San Diego)
Greg of SKA audio says:
"'However what you should look for is a 2 x 35Vac (or 0-35 x2) transformer of 300VA power or more for shared use and twin ones of min 225VA for monoblocks."
This is going to be for a pair of GB150D SKA amps that has already been populated and built. Just need the jacks, transformer, and I'm golden!
I read the thread on salvaging, but that was on consumer stuff- TVs, etc. I'd figure the industrial stuff will have good sized ones, anything else I should/need to be looking for? And when it says, min 225VA, that still means I need a min 225VA with 2x35vac correct?
I also already read the specs, and how to read for higher quality manufacturer specs on the labels. Any dangers or removal instructions? Also, the only thing I don't really get is the MHZ thing, I know that you want something that doesn't drop across the frequency spectrum, but on the label, they usually just say 50hz or something.
Thanks! - Ken
California Electronic & Industrial Supply (Great service, willing to help, great prices! and an awesome dog in the back! Located in San Diego)
Greg of SKA audio says:
"'However what you should look for is a 2 x 35Vac (or 0-35 x2) transformer of 300VA power or more for shared use and twin ones of min 225VA for monoblocks."
This is going to be for a pair of GB150D SKA amps that has already been populated and built. Just need the jacks, transformer, and I'm golden!
I read the thread on salvaging, but that was on consumer stuff- TVs, etc. I'd figure the industrial stuff will have good sized ones, anything else I should/need to be looking for? And when it says, min 225VA, that still means I need a min 225VA with 2x35vac correct?
I also already read the specs, and how to read for higher quality manufacturer specs on the labels. Any dangers or removal instructions? Also, the only thing I don't really get is the MHZ thing, I know that you want something that doesn't drop across the frequency spectrum, but on the label, they usually just say 50hz or something.
Thanks! - Ken
Well a toroid designed for mains use will be 50/60Hz. If you have a toroid much larger than 300VA you may need to soft start it so as not to cause surge. Most of them state the VA rating but you can get a generalized idea by the physical size. Keep in mind you can always re-wind a secondary if the damn thing isn't glued solid, just consider proper wire size. Salvage is the best cheapest way to obtain expensive hardware such as transformers, heat sinks, and enclosures for those of us on a cheap budget. The electronics is fairly cheap by comparison.🙂
Ummm... these guys are in the business, they will know if they have any... as far as knowing the voltage and current rating, ur likely on your own there - especially if it is still inside a bit of gear...
You can go by the core size for VA - but you may want specific VOLTAGEs for your projects. No telling what a bit of industrial gear has for a transformer. UNLESS there is a label on it that is generic OEM, not some "in-house" sort of code number - in which case you don't know and will not know unless you take it home, fire it up and see for yourself.
There is no mHz in toroidal power xfrmrs... you want a 60Hz. unit for USA use... 50/60Hz is nice but not required.
It's easier and probably cheaper to buy what you actually need online from one or more sources, including surplus houses. Smarter too, especially if you don't know what you are looking at! 😀
I'd buy resistors, wire, capacitors, diodes and stuff like that, IF you need it. definitely heatsinks if they are right for the job...
The pix on their site do not show much real surplus. 🙁
Go visit, have fun, look, ask questions, and buy only things that you know will work, unless they are very inexpensive, or you just have to have it!
Good luk!
_-_-bear
You can go by the core size for VA - but you may want specific VOLTAGEs for your projects. No telling what a bit of industrial gear has for a transformer. UNLESS there is a label on it that is generic OEM, not some "in-house" sort of code number - in which case you don't know and will not know unless you take it home, fire it up and see for yourself.
There is no mHz in toroidal power xfrmrs... you want a 60Hz. unit for USA use... 50/60Hz is nice but not required.
It's easier and probably cheaper to buy what you actually need online from one or more sources, including surplus houses. Smarter too, especially if you don't know what you are looking at! 😀
I'd buy resistors, wire, capacitors, diodes and stuff like that, IF you need it. definitely heatsinks if they are right for the job...
The pix on their site do not show much real surplus. 🙁
Go visit, have fun, look, ask questions, and buy only things that you know will work, unless they are very inexpensive, or you just have to have it!
Good luk!
_-_-bear
Yep, with the spec information- I'm sure he'll be able to find one, the issue is finding a matching set since I'm building two monoblocks, I may just go the single transformer in a huge case for the time being for ease of use and simplicity. But thank you, I wouldn't have known about the 50/60hz.
Bear, it really didn't look like much either but since it's only a 20 minute drive, why not? They're definitely not an airport hangar, but they do have shelves and shelves, and a backlot/outdoor with more stuff. Some of the transformer actually did have labels, but I wasn't looking at the time.
Bear- I agree with you in terms of buying online, however- I don't have the $200 for a pair of decent quality transformers at the moment. And if I can get these for cheap, that means altogether would be only about $200 for the pair of monoblocks which definitely make us DIYers happy knowing that the entry level pricing can best other equipment costing multitudes more.
BTW, I picked up two old school "Decade Amplifiers" for the chasis and after opening them, they have circuits with tubes! And brand new! Seems powered by those giant flashlight batteries (rectangular ones) that increase gain by 10x, 100x, etc. I grabbed them since they already had some weird speaker terminal looking (all metal). Something I can donate or trash?
Bear, it really didn't look like much either but since it's only a 20 minute drive, why not? They're definitely not an airport hangar, but they do have shelves and shelves, and a backlot/outdoor with more stuff. Some of the transformer actually did have labels, but I wasn't looking at the time.
Bear- I agree with you in terms of buying online, however- I don't have the $200 for a pair of decent quality transformers at the moment. And if I can get these for cheap, that means altogether would be only about $200 for the pair of monoblocks which definitely make us DIYers happy knowing that the entry level pricing can best other equipment costing multitudes more.
BTW, I picked up two old school "Decade Amplifiers" for the chasis and after opening them, they have circuits with tubes! And brand new! Seems powered by those giant flashlight batteries (rectangular ones) that increase gain by 10x, 100x, etc. I grabbed them since they already had some weird speaker terminal looking (all metal). Something I can donate or trash?
Hi.
If you don't find it, you can look at Antek. 41$ each, not bad.
Antek - AS-3435 - 300VA Audio Toroidal Transformers (2x35Vac)
Thanks for the link Chartal... I actually didn't think they were that cheap. I think the ones I was looking at were the Linh-Avel ones at PE. If I don't find anything this weekend, those antecs are probably the best way to go.
Thanks for all the help guys!
Thanks for all the help guys!
put up jpeg of the decade amplifier...
probably keep, especially if the tubes are usable for audio...
_-_-bear
probably keep, especially if the tubes are usable for audio...
_-_-bear
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