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I think that you have to check what happens to the system if one of them is overloaded or fails. For example what about the pumps operating at 12V?
The reverse parallel diodes should guard against that, assuming they have a high enough current rating.
I ordered a E36313A as well and delivery is confirmed Januari the 26st. Perhaps this model is produced in lower quantities or more popular than expected.
Mine arrived today so that is slightly ahead of schedule. I'm going to update the firmware first and do some tests.

My expected delivery date is now changed to March grrrrr
Repair / Beginner trying to fix Philips 212 turntable circuit
« Last post by CarlJacob on Today at 10:32:29 PM »
Hi. I am trying to fix a Phillips 212 turntable for a friend. I noticed that there was a lot of activity on this forum back i 2015 about this turntable, so I thought it would be a good idea to ask you guys for help. (I already have the curcuit diagrams and the PCB layout.)
When I turn it on and play the first record (33rpm), it works fine for a few minutes! All the internal bulbs are working, and the speed is perfect. Then suddenly the speed control goes bananas. It changes to 45rpm and stays there. There is no reaction if I touch the STOP button, but if I leave my finger on it, the 45 bulb starts flickering and when I remove my finger, the 33 button gets active for a couple of seconds, and then the system goes back to 45 and stays there.

The only way I can play records at 33rpm is to quickly put my my finger on the 33 button when it lights up an LEAVE IT THERE!

Sitting in front of the turntable all night with a finger on the button is not that interesting, so I hope somebody out there can help me. Thanks.
I can set my voltage cut-off and currently it's at 10 V even though the UPS shuts down when my my DMM value reached around 10.3 V or so.

I and currently only used 400 W and pulling 45 A from the battery but though it would be better to size up for the maximum power capacity for future-proofing.

In the manual, they say that 4 AWG is the minimum required thickness for the conductors. Knowing this and only having access to 3 AWG and 1/0 AWG, would the run-time from the cut-off voltage difference due to voltage drop make any significant difference in run-time? 5% is worth it if the cables run cooler.
I think that you have to check what happens to the system if one of them is overloaded or fails. For example what about the pumps operating at 12V?
Repair / Re: Yamaha RX-V440 turns off after 1/2s after power on
« Last post by mzacharias on Today at 10:29:36 PM »
I turned it on normally and allow it to fail. It lasted for 1.25 seconds. The initial display error message reads

"PS PRT : 23% D"

Hopefully the problem is just the power supply end and something like a capacitor or something

This appears to refer to the the microprocessor receiving about 1.15 volts at a PS input where 5 volts is the norm. This would indicate a positive voltage regulator IC is probably bad. Could even be bad solder at an IC leg.

In any case, you need to start up in Protection Cancel mode, at which point the unit will stay on so you can troubleshoot at your leisure.

Check the output of each of the IC voltage regulators, one voltage will be low or missing.

Most of this stuff is conveniently located on the "Main 3" board, shown in the upper right of page 86 of the PDF manual. This board is mounted along the top of the amplifier heat sink, and includes a rear center channel amplifier channel.

I find a long thin multimeter probe handy in these situations. If you cannot quite get to an IC output lead, get your probe on the capacitor associated with it's output.
Repair / Re: Soldering station Yihua 899D+ blown R4 and fuse
« Last post by webgiorgio on Today at 10:29:02 PM »
Has anyone the schematic Yihua 899D+ solderign station?
Projects, Designs, and Technical Stuff / Re: Double MOSFET action
« Last post by Hero999 on Today at 10:27:47 PM »
I'm not sure exactly what you're asking. Yes two MOSFETs connected back-to-back is a fairly standard way to ensure it doesn't conduct in the reverse direction, when it's supposed to be off. Other than requiring more components, the main disadvantage is the on resistance is doubled.

What does R112 and C39 do? They will slow it down, which I think is a bad idea.
I've got some allpcb boards, that the Silk screen is just awesome.   One thing is that i dont' use Stroke fonts. My tend to use Arial, and its very readable.

Same PCB font, gerber etc submitted to two manufacturers with same specs and all.. and comparable price too
Different pcb material, different solder-mask color (ok thats not an issue anyway!), different silkscreen method obviously but one came as you see, the other nice and smooth and clear to read even for their own batch code which btw, is hald the size of that on allpcb pcbs!
Is the SS issue the same on all the PCBs in that batch?  They clearly use some sort of "dot matrix" printer for the SS.  I have gotten a number of boards with less than ideal printing but nothing quite as bad as what you are showing.

I ordered 10pcs and received 13, the problem was in 6 of them
The other 7 were ok but not as good as jlcpcb board next to them
Its not "dissapointing" its juust not good.... yes they might be functional and yes they might be prototyping pcbs etc but it is not what you pay for anyway and not what you expect!
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