last last F4
Interesting drawing, but I think you'll still need something for balanced to single ended conversion, because the input you have shown on your last F4 must have identical phased inputs, only with 8V dc difference...
I bet pumpkin will kill those tl431 very fast! 😀
Interesting drawing, but I think you'll still need something for balanced to single ended conversion, because the input you have shown on your last F4 must have identical phased inputs, only with 8V dc difference...
I bet pumpkin will kill those tl431 very fast! 😀
mpmarino said:
4 times 4 is 16 wires.
2 transformers with 2*115Vac primaries and dual secondaries count up to....16 wires.
These are so small that they'll fit in a 3 1/2 " high case.
(burp, same height my Aleph-J cases will have)
Ya know,
I had a hard time deciding whether or not to put the trafo in the pre case. In the end I decided to chicken out and keep it outside. I've been having cr@p luck with noise lately - I think it's the 106dB horns' fault.
That is, when I can get back to work on this stuff - I had to put the pumpy on a high shelf
edit: Aleph J? is that anything like the Babelfish?
I had a hard time deciding whether or not to put the trafo in the pre case. In the end I decided to chicken out and keep it outside. I've been having cr@p luck with noise lately - I think it's the 106dB horns' fault.
That is, when I can get back to work on this stuff - I had to put the pumpy on a high shelf
edit: Aleph J? is that anything like the Babelfish?
Zen Mod said:
use that EI and place it in separate box ; 600VA donut is really overkill ....... even for Pumpkin
both transformers you show are probably too large ( physically and inducing hum wise) to be in same box with active electronic
Keeping the trafo in another box is not very high in the WAF - how effective is it to do a aluminum partition or an aluminum cyclinder to surround the trafo (using a tin can? ) - in terms of reducing noise? Or is it the fact that the trafo is bolted to the chassis that causes problems?
I don't mind having a larger single chassis and keeping the trafo as far away from the channel pcb as I can. But I guess if its no go - then I'll use one of those desktop computer power supply boxes to house the power circuit.
her shann
My (humble) experience is that Al is not really (or really not) good in shielding trafos radiations.
Distance is far better, or some iron-sheet.
I had good experience with little piece of wood for méchanical decoupling from chassis.
Manu
Distance is far better, or some iron-sheet.
I had good experience with little piece of wood for méchanical decoupling from chassis.
Manu
Manu said:
Whatever material you choose for the shielding, keep in mind that it's a matter of thickness. Steel can offer the same shielding as aluminum, but require less wall thickness.
Anyhow, you need more than a tin can to make any significant shielding. I did some testing on the subject, for a 1000VA torodial trafo you need approx. 12mm steel to get the magnetic field under control adequately for placing it next to a sensitive circuit.
Magura 🙂
Copper don't hurt but is not so efficient against magnetic radiations. Actually only u-Metal is.
If magnetic strays is the problem. Distance cures it completely. Depending on how strong the radiations are (how big the trafo, but not only) a of course. So " ... both transformers you show are probably too large ( physically and inducing hum wise) to be in same box ..." (Zen Mod)
Manu
If magnetic strays is the problem. Distance cures it completely. Depending on how strong the radiations are (how big the trafo, but not only) a of course. So " ... both transformers you show are probably too large ( physically and inducing hum wise) to be in same box ..." (Zen Mod)
Manu
Manu said:
Free.....and a lot lighter! The boxes I ended up making for shielding the before mentioned 1000VA trafos, are even heavier than the trafos themselves, tipping the scales around 12kg a piece for the shields.
Unfortunately distance is an opposite liniar function of WAF
Magura 🙂
Soon we will all get spam mail on how to get big peckers.🙄
Anybody has experience with the materials from this site?
http://www.lessemf.com/mag-shld.html
Thinking of getting the Magnetshield 4 inch ribbon, wrap it around a big tin can (a few layers?) and covering the trafo to see if it helps.
Why are we so fastidious when preamp manufacturers seems to have no problems? Don't see many 2 box solutions for commercial preamps.
Maybe I should look for smaller trafo - maybe 100VA - except it is hard to find a 80-100VCT small trafo. Any sources?
her shann
Anybody has experience with the materials from this site?
http://www.lessemf.com/mag-shld.html
Thinking of getting the Magnetshield 4 inch ribbon, wrap it around a big tin can (a few layers?) and covering the trafo to see if it helps.
Why are we so fastidious when preamp manufacturers seems to have no problems? Don't see many 2 box solutions for commercial preamps.
Maybe I should look for smaller trafo - maybe 100VA - except it is hard to find a 80-100VCT small trafo. Any sources?
her shann
hershann said:
You are wrong.
Placing the transformer in a separate small shabby case is very common, the ones which also have the rest of the PS in a separate box are un-common and only a handfull.
There's even a straight-6 boxer pre-amp.
(can't wait to hear what the Woody-Pecker has to say about transformer size)
AR2 said:
why - that can be really overwhelming experience
.......AR2 is right - in many commercial preamps man can find eeny weeny xformers , which radiating field is way weaker than of any xformer you (hershann) posted ........
on the other side - Pumpie with Shunty isn't everyday's preamp ...... just look at amount of energy it needs, without any additional fancy gadgets
I think that a hi end preamp in 1 chassis has probably gone thru much R+D in this regard. The maker likely went through several layouts and several trafos before settling in on an arraignment.
I'd rather just stick it outside😀
Manu said:
for piece of mind - untie them , squeeze little of goop with tiny blade , tie them again
Manu said:
Great !
Idea of puting 2 Pumpkin one on top of the others is simply great. And a second after that thought, I realise that Heatshrinks are missing...Are You able to leave it as it is on a picture with Heatshrinks mounted?
About the enclouser - there will be an selector - rellay input switching, correct?
Very nice Alu front ....
spavleski said:
Great !
Idea of puting 2 Pumpkin one on top of the others is simply great. And a second after that thought, I realise that Heatshrinks are missing...Are You able to leave it as it is on a picture with Heatshrinks mounted?
About the enclouser - there will be an selector - rellay input switching, correct?
Very nice Alu front ....
besides somewhat different thermal behavior in time domain (comparing to side by side usual positioning ) , for that physical layout , one need to use sideways (outside) looking multiturns, at least for lower pcbs .
Attachments
spavleski said:
maybe few matched outputs ?
by mistake soldered in Shunty?
edit:
I'll have my dreky Japanese 4-deck pot ( Franco-Osterreich connection 😉 ) probably on Friday , along with tiny DACs .........
Zen Mod said:
maybe few matched outputs ?
by mistake soldered in Shunty?
It was not mistake but to have the exactly the same amount of dreky curent going to shunts in order to have the same temperature on all heatshrinks 😉
Zen Mod said:
spavleski said:
It was not mistake but to have the exactly the same amount of dreky curent going to shunts in order to have the same temperature on all heatshrinks 😉
yeah ....... pretty engineer - like approach .......
"look woman, it isn't hole of my soldering iron - in your new carpet ; that's probably factory defect ......... "
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