Shopping Advice

[keantoken]

Hi all.

I want some advice from those of you who have been buying your parts online. I need to squeeze the most out of my money.

Do you know where are the best deals for the following items?

1: 12V SLA batteries (over 5Ah, preferably higher than 7Ah)
2: Large assortment of metal-film resistors of every value (E6 is fine).
3: Similar assortment of small caps suitable for audio and RF decoupling.
3: Reservoir/filtering caps.
4: PCB etchant
5: heatsinks
6: plain vanilla PCB boards
7: transformers

I am interested in where you usually go for these items, when you need to squeeze your wallet.

Thank you for your advice,
- keantoken

 

[theAnonymous1]

I can give you a partial list.......

1: Try your best to find a store locally that sells them; shipping charges usually kill any discounts you will find online.

4: The cheapest etchant you can get is 1 part muriatic acid to 2 parts hydrogen peroxide (3%). Do some research first if you've never used this combo before, it's toxic and dangerous.

6: I buy all my PCB stock from ebay seller ABCFAB. He has great service and will cut the boards for you if you ask.

7: I don't think there is such a thing as cheap transformers.

 

[keantoken]

7: I don't think there is such a thing as cheap transformers.

I found someone that recommended this:

http://www.radioshack.com/product/index.jsp?productId=2102703

Exactly what I need for this:

http://www.diyaudio.com/forums/showthread.php?s=&postid=1847276#post1847276

- keantoken

 

[SY]

For cheap transformers (but limited selection), Apex Jr and Antek. Edcor is a highly-thought-of source for relatively inexpensive audio transformers. I've used Allied's house brand power transformers (probably Hammond) with great success.

 

[keantoken]

I found this, I'm pretty sure it's what I want.

I tried looking up the benefits/downfalls of toroids but it seems to be a tossup.

I would go for the toroid right now because of lower EMI...

http://www.antekinc.com/trans.html

I will get the 15-0-15 50VA one and step down to 13.8V using 7x12's or something. After I get bored with that I might build my own + and - regs.

Now what about resistors? How the blip do you guys get all your resistors? Radiosnack only has carbon comps, I want to move up to metal film.

Thank you for your help,
- keantoken

 

[SY]

kt, I had been getting good metal film resistors from Halted. But since leaving California, I need to find another source myself. Where in Texas are you?

Fortunately, mf resistors are pretty cheap even at new retail. Digikey and Mouser have them at attractive prices.

 

[keantoken]

I will look through Mouser and Digikey and see if the filter options give me the range of values I want.

EDIT: Am I going to have to select all the resistors I want manually?

Thanks,
- keantoken

 

[keantoken]

Okay, this is exactly what I was looking for... Except a little suspicious.

What can you say about this?

http://www.rapidonline.com/producti...9_1244270302_e4ec5b71326b7b3b9bec862412fb550e

- keantoken

 

[sidsparks]

Rapid are a UK based distributor so I guess the cost of shipping will make it a no go.

 

[keantoken]

 

[amc184]

For caps and resistors I almost always use Farnell (Newark for you in the USA). For transformers I second the suggestion of Antek, shipping from them is a bit of a killer for me, but not for you.

 

[ChrisA]

Hi all.

I want some advice from those of you who have been buying your parts online. I need to squeeze the most out of my money.

Do you know where are the best deals for the following items?

1: 12V SLA batteries (over 5Ah, preferably higher than 7Ah)
2: Large assortment of metal-film resistors of every value (E6 is fine).
3: Similar assortment of small caps suitable for audio and RF decoupling.
3: Reservoir/filtering caps.
4: PCB etchant
5: heatsinks
6: plain vanilla PCB boards
7: transformers

I am interested in where you usually go for these items, when you need to squeeze your wallet.

Thank you for your advice,
- keantoken

ANy cheap car battery has way more than 7AH. Even a used car battery.

Transformers? What kind? Low or high voltage power, audio? You can salvage them from broken equipment. Wall worts, microwave ovens, broken guitar amps and so on. The last set of transformers I got where salvage from a high powered guitar amp. Hammon wanted $350 for the pair but I paid a LOT less.

You can also re-wind transformers too if you really need to.

People will give you old CRTs, TV sets and computer monitors. They are hapy to have you haul them off. I salvaged a pickup truck load of these and now have boxes of old transformers, inductors, caps, hookup wire. and many good heat sinks of all sizes After a while i found out that the high end CRTs made by Sony have very much better parts inside. 21 inch computer monitors are a gold mine.

I used a propane plumbers torch to de-solder. It burns the PCB but heats the solder so fast the part is not even get warm.

Google for "Dan's Small Parts" Dan has some deals on caps, like a kit of 100 for $5, cheap PCB aterial too. Buy one of his 2 pound bags of "junk" but you will need an LCR meter to soft the 4 or 5 thousand parts - mostly disk caps.

Google for "resistor kit" (with the quotes) will turn up several

Learn to build with SMT parts. SMT is better than though hole in every way and the parts are cheaper and you don't have to drill all those $&%^# holes.

 

[dangus]

For cheap SLA batteries, find an unguarded battery recycling bin, or scrapped computer UPS units. Batteries often get replaced in pairs when only one is bad. Some battery stores (as in car, industrial, etc.) have bins outside.

Cheap transformers: I've picked up new-in-box Hammonds very cheap at a ham radio swap meet.

Heatsinks: Old receivers or integrated amps that used unavailable amp modules are fair game.

PC board stock is much cheaper if you buy a big sheet, or sometimes surplus dealers have leftover chunks from local PCB manufacturers.

Etchant. I just buy the gallon jugs from the local electronics shop. Shipping corrosive chemicals may be costly.