Check your led polarity on the side which didn't light up, that would be my guess.
Make sure the power lead is disconnected and the caps are completely discharged first.
Take your time to get the psu 100% and stay safe !
You'd think the external chassis would provide the shielding, but not completely in my experience, I've had vintage pre/power combos that would hum like crazy through the speakers if the preamplifier is on top of the power amp. Lift the preamp amp and the hum would get audibly quieter the further it got from the power amp. Mind you, that was a poor 1200VA E-I transformer in the power amp that had a hard 40 years with no soft start and had some mechanical hum anyway.
I think it's primarily down to the winding+core quality, followed by potting. I've got a relatively cheaper Toroidy Audio grade coming for my EF3-5 so will be interesting to compare with the Supreme Audio grade I have here already.
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For safety reasons you'll want everything in one chassis, with a single mains earth.
Dual chassis means detachable earth cable, which is no good.
Dual chassis means detachable earth cable, which is no good.
Hi Gent's, I have a question may be is stupid or irrelevant. have you also match the Q107 with Q108?
Fixed! The LEDs were installed opposite of what they should have been on the -71vdc side of the psu.
Is one Hypex Soft Start module sufficient for both of my Antek 500VA transformers wired in parallel to it? It's specification is up to 1500VA and 6A continuous operation.
https://www.hypex.nl/products/smps-family/softstart-module
https://www.hypex.nl/products/smps-family/softstart-module
Hi Guy's,
Just a very quick update.
The boards has been shipped from the pcb manufacturer.
Just a very quick update.
The boards has been shipped from the pcb manufacturer.
Well I know but who knows if there is a double secret rule of thumb this novice doesn't know about? 😉 I am just trying to have someone double check my assumptions!
Shielded it is then. If they have their own shielding, I suppose I could just put them in a high temp plastic enclosure. Maybe even laser cut acrylic (I have a new giant laser machine I am just itching to use for personal project stuff)....... See through enclosure with chrome toroids and nice, fat, blue caps sounds fun..... now I might just do separate PSU just for the aesthetics lol.
Two 500VA transformers parallel, making 1kVA total, on a 110V net will draw up to 9 A
Non-ferrous metals perform poor for shielding low frequencies, iron cabinets are better choice then aluminum for this purpose.
So should I consider a dedicated soft start for each 500VA transformer because of the 6A continuous limit of the Hypex soft start?
I doubt you will draw more then 660 Watt continuous (6 A) while playing music in an domestic setting, I would not drop the Hypex soft start for that reason. However I have no data specific to their circuit, or your use of the amp, so this is a general assumption. Dedicated soft start for each transformer might bring up complications, like dual power switches, troubles with protection circuits and/or remote switching by preamp. In the end you decide.