|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
104.14.166.252
....finally.
Had one of those deeply depressing situations last night when I first put power to it: no voltage on the outputs, no LED illumination, no nothin'. 120v at the IEC filter pins, so incoming voltage there, good fuse, and 120v to the transformer. But at the board inputs (hot to ground) I was getting 36v. Huh? Transformer should be at 14v wired in series. That's when I discovered the secondary lead wires were coated. The ends are tinned by the factory, but when you cut them back (for neatness) like I did, you're down to enameled wires. No burning it off with a soldering iron either (yes, I tried) -- gonna need a solder pot which I don't have. Fortunately I had purchased 2 transformers, so I popped in the other with the secondary leads at full length, and life arose from nothingness. Then came tuning for the output voltage. With this design, it's a matter of finding the right zener diode. Same value, but apparently there is a wide variation in tolerance on these, so it's down to swapping different ones until you find the right one. Wish it was as easy as Manny's with a trim pot. :) Not exactly 9 volts, but that's as close as I could get with the zeners I had to try. Don't think it will matter with the Remedy reclocker -- the factory wall wart puts out 9.16, and the iPower puts out 9.26 (both unloaded values though). What's nice with this AMB supply though is that I'm getting 9.11 volts unloaded, and the exact same 9.11 volts loaded down pretty well with a 50 ohm resistor across the outputs. Now time for some listening, but I'll let it break in for a bit first. Hope it was worth the effort!
Follow Ups:
Just a word on transformer wire enamel-
if it is not 'solder-able' the solder pot won't help....
a blade is easiest- even at 24 gauge-
Happy Listening
Ugh. Good to know on the solder pot...thanks. Guess I'll give the scraping another try when I can muster up the patience. :) Lesson learned.
The trim pot did make it a snap. Super clean install in the enclosure. Congratulations!
I'm still figuring out the enclosure for mine. I'll get it there. It's the most fun part of the whole thing aside from when it actually helps make music.
Be sure and give us some pictures when you're done. Real intere4sted to see what you come up with.
Looks like there is enough room to upgrade that pipsqueak tranny! Then and only then can you say that it's really alive. T456
If you'd actually read the original post, you'd see that the power supply will be used for a reclocker, which is a steady-state device. Since you don't know what that means, it means that if the reclocker needs 500mA to operate, it will use 500mA at idle, and will use the same 500mA if you're at decibel levels that would blow the windows out of the house. A larger transformer would do absolutely nothing to improve the sound, and if anything would probably degrade the sound due to its radiated EM field being in closer proximity to the rest of the circuit. Sorry that your "bigger is always better" nonsense fails again.
If a bigger transformer can cure the dt's as bcowen suggested in Central, I'm sure it would also be appropriate in this situation also. It is a virtual certainty that I never said always. Most of the time or at the very least very often is my position. Looks like it might be too big in this situation from an EMI point of view??? The fact that you brought up the IMPOSSIBILITY of a bigger transformer manifesting an improvement in this steady state situation implies a possible improvement in a non steady state situation from a larger than "necessary" transformer. Thanks for the validation. EMI is only one factor. If you have never actually compared a larger transformer in a steady state application you can't say 100% for sure it doesn't sound better. T456
Edits: 11/13/16
. . . would probably degrade the sound due to its radiated EM field being in closer proximity to the rest of the circuit
Not to mention a larger transformer's decidedly un-pipsqueaky tendency to pass mains-borne noise to the circuit and vice versa.
D
.
Nice job.
Where did you get the 2.5mm plug from? looks heavy duty.
Dan Santoni
Thanks!
The plug is an Oyaide DC2.1G. I purchased it a while back intending to use it for something else, but never did. Came in handy for this project. Seriously nice plug, and IIRC, was quite reasonably priced for something with the quality level of an Oyaide product.
Beautiful work, Mr. C....you could be in business by the looks of it.
Thanks, Alan! I've built probably a dozen kits over the years from accessories to tube amps, but all of those have been complete with everything needed. This one required buying a chassis and many of the parts separately, as well as calculating values for some components based on the desired output voltage. Really nice design with a high quality circuit board and excellent instructions, but still a bit more involved than I've been used to. Was fun and interesting to build though, and I'm just happy it actually works. :)
You could have just taken a knife and scraped the coating off the copper.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Tried that. Problem is that it's about 24 gauge wire (it's only a 15va tranny), and just minor bending back and forth is enough fatigue to cause it to break. After snapping the first two ends, I gave up. With enough time and care it could certainly be done, but that would have required patience beyond my capability and continuing to ignore the other transformer sitting there looking at me. :) I'm sure one of my local buds has a solder pot I can use, so I'll salvage the first one for the next unit.
"...24 gauge wire...."
sorry, I missed that.
Yes, that would make it much harder to do.
I like your plan.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Post a Followup:
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: