Antek Toroidal power transformer for Step-up, Measurements (part 1/2)

[CharlieM]

Originally Posted by bolserst

Maybe I'll setup a donation fund to pay for the sacrificial test
Seriously though, I may do that early next year if I can find the time.
It would need to be a high frequency (1kHz maybe) long duration test, increasing voltage slightly every week if we really want to know what it can reliably handle.

Hey, I'm throw in a few bucks for the cause... just PM me an address!

[chinsettawong]

Nice report. Thanks for sharing.

Wachara C.

[geraldfryjr]

Yes ,Bolserst,those are the the same links to the methods I use I remember them quite well.
I do have a capacitance meter but not an inductance meter yet as it is on my list of things to have to build next.

I was referring to the primary having very good coverage of the core as that makes a big difference in itself.

Again Thanks !!!

jer

[fperra]

AnTek has another transformer with similar specs but rated at 100VA and a shield between the primary and secondary. Also has an external magnetic shield. This might be a better choice. Only about $10 more.
Antek - AS-1206

[dochungwell]

Hello All,

Well I thought the Antec transformers were a great buy...so I bought 20 of them (for myself and friends ESL builds). I am using them nearly everyday with no alterations and have not experienced any signs of arcing.

I have not measured the capacitance of my panels, however they measure 15"x48". I have essentially deviated from the 1ohm/10w resistor to 8ohm/20w, some will argue there would be an appreciable loss of high frequencies, but this was not my experience.

I am essentially using a 3kv bias power supply and my 6um myar is stretched to just over 2.5% elongation.

My Amp is an ADCOM GFA-535II. got it on EBAY for 100.00, it sounds fantastic, however I use it like a rented-donkey!....If it smokes i'll get a bigger one....

In practice it has been working flawless and the only arcing we had to deal with occurred between the XLR connectors if the heat shrink was not on properly (nail polish resolved that issue). Currently several of my friends now have there set-up using those trannies a over time a better longitudinal study can be observed.

I believe these were an excellent find, thanks again Charlie!

Best Regards and Happy Holidays,
Jerry

[tyu]

Just the Facks...real world..that tells a lot for the $$$ thay look like a stel..thanks

[dochungwell]

I too would be curious to hear what the differences between the Antec AS-1206 and the AS-0506?

[dochungwell]

Bolserst,

question, after your analysis of the Antec AS-0506, what if anything would you change?

And what affect if any would it have on either sound quality or Amplifier load resistance?

thanks,

Jerry

[bolserst]

Originally Posted by dochungwell

Bolserst,
question, after your analysis of the Antec AS-0506, what if anything would you change?
And what affect if any would it have on either sound quality or Amplifier load resistance?

The things I would change are:

1) Increase power handling capability by either using more primary turns, or a larger core.

2) Wind the secondary with insulation tape between each layer. This would not only avoid any potential arcing issues, but also cut the winding capacitance by 50% - 75%.

3) In general I like to minimize winding capacitance at the expense of increased leakage inductance. For the same HF bandwidth limit, a design with lower capacitance(but higher leakage inductance) allows you to increase the value of the series damping resistance for the same HF roll off. This makes the HF load impedance higher in magnitude and the phase more resistive, both of which makes the load easier for amplifiers to drive. It also makes "tuning" of the series resistance less critical.

[bolserst]

Originally Posted by arend-jan

Perhaps the other one could be sacrificed for some empirical data gathering? Or in other words turn up the input voltage until it does arc

After thinking some more about the sacrificial test, it struck me that I can get the information we are after without having to destroy another transformer. What we want to know is at what voltage the insulation between two adjacent wires of the secondary will fail. I have the wire I unwound from the first transformer, so all I need to do is twist two wires together for a foot or so and then apply the AC voltage between them. Increase the voltage and wait for the fireworks.

Should probably have some time to set this up next week.
Will probably set up a dozen or so twisted pairs to see if they all fail at similar voltages.