It seems to be correct for me 👍
Just to clarify for the others: the red circle only appeared in the course of a question and is intended to show that there is no contact between the cl60 and the board.
Sorry, I must have read it wrong somewhere
Please ignore what I said about the SLB supplys voltage drop in post #557
Hi, I will order the chassis for my Aleph 60 monoblocks soon and would choose the Mini Dissipante 4U300, which has the same height and depth as the normal Dissipante, but with an inner width of only 250 mm - would it work too re heat?
Does anyone have experience with it? Many thanks in advance
Does anyone have experience with it? Many thanks in advance
My F5 is in a mini Dissipante 4U300 and the sinks are typically around 50C. I expect the Aleph60 monos to be a bit hotter than that.
https://www.diyaudio.com/community/...s-chassis-builders-thread.382316/post-6968327 Posts 328 and 330
https://www.diyaudio.com/community/...s-chassis-builders-thread.382316/post-6968327 Posts 328 and 330
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There is good news: Randy's Care-Paket with boards and parts for the Aleph 40 build arrived at my place. I also gathered most of the PSU parts. I am a bit sick at the moment, but I hope to start soldering next days. Most chassis works are already done - the 5U 400 is a real monster compared to the looks of an 4U 300 enclosure.. Transformers should arrive next days, wish me luck!
Hello,
I finished building some Aleph 2 mono-blocks a week or so ago. All parts ordered for both the audio boards and the power supply were those listed in Classic Aleph 2 Build Notes 1.0a.pdf, and the matched devices are from the group buy. I used Antek AN-6435 transformers. Immediately upon power up, the boards are drawing about 3.2 amps before starting to decline, and after a couple of hours they are drawing about 2.8 amps. This is with the current adjustment pot maxed out on both amps, and AC gain set to 50%.
I am attaching the sheet that shows the individual measurements. These are measurements after adjusting the pots. I no longer have the pre-adjustment measurements. I measured output devices then the source devices for each channel, and the cold measurements current drop happens quicker than I can measure each device, so those numbers are suspect. The After ~1 hour measurements actually took place after 2 hours, as by that time the current draw is no longer declining.
My questions is; any ideas as to why am I not able to get a stable 3 amps of current even with the current pot at maximum? I've double checked that all parts are correct according to the document.
P.S. Oops, on the sheet I miswrote the Current Source Mosfet 1 Warm Right value. It should be .449, not .499, and the sum figure for that column should be 2.764, not 2.814. I had to copy to another sheet because my handwriting on the original sheet was unfit for publication 😳.
Thanks,
Alan
I finished building some Aleph 2 mono-blocks a week or so ago. All parts ordered for both the audio boards and the power supply were those listed in Classic Aleph 2 Build Notes 1.0a.pdf, and the matched devices are from the group buy. I used Antek AN-6435 transformers. Immediately upon power up, the boards are drawing about 3.2 amps before starting to decline, and after a couple of hours they are drawing about 2.8 amps. This is with the current adjustment pot maxed out on both amps, and AC gain set to 50%.
I am attaching the sheet that shows the individual measurements. These are measurements after adjusting the pots. I no longer have the pre-adjustment measurements. I measured output devices then the source devices for each channel, and the cold measurements current drop happens quicker than I can measure each device, so those numbers are suspect. The After ~1 hour measurements actually took place after 2 hours, as by that time the current draw is no longer declining.
My questions is; any ideas as to why am I not able to get a stable 3 amps of current even with the current pot at maximum? I've double checked that all parts are correct according to the document.
P.S. Oops, on the sheet I miswrote the Current Source Mosfet 1 Warm Right value. It should be .449, not .499, and the sum figure for that column should be 2.764, not 2.814. I had to copy to another sheet because my handwriting on the original sheet was unfit for publication 😳.
Thanks,
Alan
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https://www.diyaudio.com/community/attachments/classic-aleph-2-build-notes-1-0a-pdf.1054738/
The schematic in the document does not include the correct values, but the values are listed in the BOM inside the document.
The schematic in the document does not include the correct values, but the values are listed in the BOM inside the document.
Started soldering the Aleph 40. Due to the quarantine I am in, it looks like the amp may sing in my living room this weekend.. I had some old transistor sockets to socket the pots, so I can take them out to measure them after setting the desired quiescent current and AC current gain. Still have to mount the boards to the heatsink, solder the MOSFETs and do a lot of wiring and beeping..
This has me curious. My two multimeters are medium priced, and they seem very inaccurate. Resistors are always measuring lower than they are labeled. What brand of multimeter are people using for accurate resistance measurements?
There is a german-developed and chinese-made transistor tester device that also does great in measuring resistances, capacitance, inductance. I use it a lot and it never let me down yet. I took a picture how measuring trimpots work with this device. Search for Mega328 or GM328 on eBay.
I use Kester leaded 63/37 eutectic solder (24-6337-0027). The best solder I tried yet.
Picture was shot after cleaning the flux residues. Most parts where soldered from the top side of the PCB first, and checked on the "solder side" later. Cheers!
What (general) values are you talking about? Sounds silly to ask, but how far are they off? You're not measuring them in-circuit are you? What precision/accuracy are you expecting? Do you want to pay to have it calibrated semi-annually?
For anything lower than 10R (ish), you're not going to get a high precision measurement w/o good measurement technique and a meter that is designed for low resistance.
By contrast, for things in the multi-kilo / mega-ohm range, 'the aljordan circuit' may have less resistance than the resistor you're trying to measure. You don't want to put your body circuit in parallel with the resistor. Don't touch the resistor leads or the conductive ends of the probes during measurement. Try it both ways and see how the results may vary.
Lastly... change the batteries in your DMM and see if it helps.
Anyway... I wouldn't give it much of a thought. The ones you have are likely perfectly suited to the task at hand.
To really answer your question... A Fluke 287 or 289 is an exceptional choice IMO, but I use <$20USD models from a popular online retailer.
Cheers