[splaz]

I was just wondering this as I might have to make another order with tangent.

Basically a regulated 24V DC plug pack is fairly expensive, even at a trade price through my dad or mate.

A TREAD or STEPS would be even more expensive but seem like a better option in regards to giving a cleaner power supply and a lot more flexibility.

Opinions anyone ?

While I'm at it, stupid as this question may seem, what are the main differences between the TREAD and STEPS... ?

From what I can tell TREAD is a little stripped down with less filtering and without an on-board toroidal transformer.

Also thought I might slip in this last question at the end, is the TREAD more complicated than basic designs because it's adjustable or that the TREAD is just better designed and adjustable?

like so: http://www.jaycar.com.au/products_up...Large_5705.jpg

I'll stick up the schematic if I can find it but it's really simple anyway.

I know that's a +-15v but consider two TREADs then or cut that in half and compare it to a TREAD.

Sorry if some of this sounds noobish but I'm still not too great at the whole theory thing... good at the burning my hands part though.

 

[Polaris111688]

http://www.tangentsoft.net/elec/psu-tests/

The TREAD/STEPS outperforms the Elpac WM080 regulated power supply significantly.

 

[tangent]

Quote:

Originally Posted by splaz A TREAD or STEPS would be even more expensive

Really? Here in the US, the cheapest option for a linear-regulated wall wart style power supply is the Elpac WM080, at $30. The full TREAD kit is $17, and you can find a basic unregulated wall wart to go with it for $5-6. If you put the TREAD in the case with the circuit it's powering, it's cheaper than the Elpac. If you kit your own parts, it's cheaper still.

I guess you're either adding in the cost of a separate case, or you're comparing against a switching regulated power supply. If it's the latter, I'd want to do noise and isolation tests on it before using it to power audio equipment. Some switchers are suitable, but most are not.

Quote:

is the TREAD more complicated than basic designs because it's adjustable or that the TREAD is just better designed and adjustable?

The latter. While you can build an LM317 based regulator using just two outboard resistors, you don't get the full promise of the regulator's capabilities. So, you add two filter caps to lower the noise floor. That in turn requires the protection diodes.

The only other "questionable" part is the film bypass across the main filter cap. That's just a nicety, and you can leave it out if you want.

 

[SnoopyRocks]

Quote:

Originally Posted by tangent Really? Here in the US, the cheapest option for a linear-regulated wall wart style power supply is the Elpac WM080, at $30. The full TREAD kit is $17, and you can find a basic unregulated wall wart to go with it for $5-6. If you put the TREAD in the case with the circuit it's powering, it's cheaper than the Elpac. If you kit your own parts, it's cheaper still.

Jameco has cheaper linear regulated supplies than that

]http://www.jameco.com/webapp/wcs/sto...goryId=453520]
http://www.jameco.com/webapp/wcs/sto...egoryId=453530

In particular, these two stand out as great deals.
+-12V@310mA,+5V@1A, $9.69
24V @ 500mA, $13.15

 

[tomb]

I'm glad you brought that up!! I've been eyeing those JAMECO power packs and wondering about them (besides ordering DIP-8 BUF634's from them - they have them in stock!).

I am hoping Tangent might offer an opinion on their suitability. They have some with much higher amperage than the typical regulated ELPAC at 0.3A, too.

Also, was humbly wondering about this:
Quote:

"If you put the TREAD in the case with the circuit it's powering, it's cheaper than the Elpac. If you kit your own parts, it's cheaper still."

I thought the TREAD kit was a pretty good deal. It's not possible for the same quality parts with less, is it?


P.S. JAMECO also has a tabletop wart at 24V-1A for $18.65.

 

[tangent]

Quote:

Originally Posted by tomb I am hoping Tangent might offer an opinion on their suitability.

If I knew anything about them, I wouldn't have said what I did above.

Jameco's website offers no useful information, so I still can't tell you anything.

Quote:

It's not possible for the same quality parts with less, is it?

If you want to use exactly the same parts that I put in the kit, then yes, I believe you're right that it's not possible to kit your own parts for cheaper. You would either have to order from multiple sources so shipping kills the deal, or order from Digi-Key where high prices and minimum quantity limits kill the deal. But if you're willing to select a different regulator, you can put everything together with parts from Mouser for about $14, including the board. If you had to order parts from Mouser anyway, then the extra shipping charge doesn't matter.

 

[tomb]

Thanks for the answer. The TREAD certainly seems the way to go, and makes the question of the JAMECO "linear regulated" power supplies moot.

 

[splaz]

Quote:

Really? Here in the US, the cheapest option for a linear-regulated wall wart style power supply is the Elpac WM080, at $30. The full TREAD kit is $17, and you can find a basic unregulated wall wart to go with it for $5-6. If you put the TREAD in the case with the circuit it's powering, it's cheaper than the Elpac. If you kit your own parts, it's cheaper still. I guess you're either adding in the cost of a separate case, or you're comparing against a switching regulated power supply. If it's the latter, I'd want to do noise and isolation tests on it before using it to power audio equipment. Some switchers are suitable, but most are not.

You must have missed the part where I said I could get one at trade price. My mates dad has an electronics repair business and my own dad is a sparky.

After the currency conversion and shipping, plus populating the board, a TREAD populated myself would wind up being slightly higher in price and a STEPS would definitely be more.

The kit is nicely priced and would probably end up roughly the same or slightly more.

$17US = $23AU. Plus a plug pack ~$15 for $38AU total. Which is around about how much one with a discount would be.

But I would be planning on using a toroidal transformer, which I can get at discount as well, but even then they are still quite expensive. Which means then I'd probably get the STEPS anyway. Actually I think I might get a STEPS board and a TREADs kit. I think I have a use for both.

Well cheers for the answers.