center tap transformers

kobresia · Joined: Jul 14, 2005 Posts: 10 Location: Norway

I seem to be unable to find a local supplier for center-tap transformers. A few questions, please forgive my ignorance, if any:

1. Any suggestions as to where one might find them (preferably Europe, also preferably small and reasonably light)?

2. I have seen mention of simulating a center-tap transformer with a standard dual secondary transformer. Connecting one up in series and using the center as ground gives unequal voltage for each side, with one side being much larger. Is there a simple, safe way to simulate this?

3. Where might one find center-tap transformers to salvage from common electronic equipment?

4. Simply using literal ground as ground would be possible, wouldn't it? Still, I suppose my wooden case isn't exactly well suited. Any ideas?

Macaba · Joined: Jul 13, 2005 Posts: 160 Location: UK

The shocking thing I found was that even though most transformers don't specify it on their respective websites, they ARE actually center tapped.

The best thing for you to do is GO to a local shop, LOOK at some transformers to see if they have 3/4 taps on the secondary.

Failing that, see if these nice people will ship to you?:

http://www.rapidelectronics.co.uk/rkmain.asp?PAGEID=80010&CTL_CAT_CODE=&STK_PROD_CODE=M30993&XPAGENO=3

kobresia · Joined: Jul 14, 2005 Posts: 10 Location: Norway

No, the tap configuration is clearly stated in the catalogues of my usual suppliers, there's no center tap on any of them.

Rapid Electronics only ship abroad for orders over £500 in value... I'll check with others, I have a list I can go through.

For scandinavians: Can you recommend other suppliers besides Elfa, Labb, Trimlog, Bhiab?

Macaba · Joined: Jul 13, 2005 Posts: 160 Location: UK

Another thing to note, if it states that the secondary is 0-12v, 0-12v, or whatever voltage, as long as it says it twice, its likely to be center tapped.

v-un-v · Posted: Thu Jul 28, 2005 1:24 am Post subject:

deknow · Posted: Thu Jul 28, 2005 7:17 am Post subject:

a customs trick that i've always used (and i think it has always worked). don't include an invoice, or anything that makes it look like a trade or sale (you can always mail a letter separately). instead, i enclose a store bought card (probably best to avoid birthday card or anything that a date could be confirmed for) saying, and make it look like a gift. at least to the countries i've shipped to, gifts below a certain value are exempted from being taxed. i haven't done this in years, so your milage may vary.

deknow

kobresia · Joined: Jul 14, 2005 Posts: 10 Location: Norway

It would be very nice of you to help me, if you're offering, v-un-v (or anyone else for that matter). Actually, there's no customs tax on items below about £18 in value, excluding shipment price, so this won't be a problem. (So the value should actually be clearly stated on the letter. Even if the value would be higher, the only consequence would be a 25% extra fee for me when I collect it, but I assume this can be avoided.)

The Rapid part number is 88-0265, 6VA miniature transformer, 0–15, 0–15V, price £3.30. If you could find out the price for delivery to you and the postage for a 200g letter (or so) to Norway, I could paypal you the total (I assume you used PayPal for the SoundLab pcb). So, if you want to do this, just PM me with the total price and your paypal details, and I'd pay you up front. Sound ok to you?