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General Chat / Re: Would you do this? weighing possibly dumb idea.
« Last post by cdev on Today at 01:22:34 AM »
This is what's happening, this is taken as I rotate the inductor crank.

 I should be able to isolate and fix the problem today, with a little luck.

This is with the sensitivity turned up a bit higher than optimal so you can see the roller cutting in and out. This is receive only so far, I need to get my ticket and get a rig set up to use the tuner, but I can't even think about using it for anything like that until this problem is fixed.

The picture above of the bearing doesn't really tell the story, although it hints at it, because it shows how the black gunk comes out of the well where the roller bearings are, even right after its been cleaned. I had the issue under control briefly but for better or for worse, I stirred it up again, by trying to clean it a bit more, and since there still was black gunk in there, then the problem came back.

Whatever was in the lubricant they used (some carrier and graphite) its usefulness is "debatable" to put it kindly..

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Microcontrollers & FPGAs / PSoC: CY8CKIT-059 first impression
« Last post by technix on Today at 01:18:07 AM »
I have received my dose of PSoC. And it is bitter, at least for now.

First off: CY8CKIT-059 have literally the lamest package I have ever seen. It is just a piece of thick cardboard with a hole cut in it, and some adhesive paper covering the hole to hold the board inside.

Getting the board out - well there is a PCB USB connector. How much more money would it cost to put an actual USB connector there? Just use a micro-B connector as you do on the very other end of the same PCB. Thinning the board down to 1.6mm will more than make up the cost of adding a connector. PCB connectors rarely get reliable unless you put the damn metal shell around it, which actually holds the tab against the board. It also damages the mating connector by putting excessive stress on the spring tabs on the shell. Now I have to either find a shell that fits the board, or solder a SMD USB Type A connector on this mess. Of course I have to solder the connector shell too so some solder mask on the back have to be filed off to make the required pads. Ugh.

Soldering the pins: The board is thicker than usual, so pin soldering is a bit more difficult. Also why is the way too commonly used RESET button and JTAG connector missing?

Now the software. PSoC requires the use of a Windows-only software. This is really a non-starter for me but for the sake of experiment I grabbed an evaluation copy of Windows 10 and installed it in a virtual machine. Speaking of, using USB devices though USB pass through in virtual machines isn't that smooth as you think. Installation speed is acceptable though. Now getting into the interface I am utterly confused - this really is an IDE too hard to work with. Well let me load up an demo project... Well now I am in for even more confusion. The software looks like an awkward combination of some old version of Quartus and Visual Studio. And even though I am using the latest PSoC creator 4.1 it still does not support HiDPI display and looks HORRIBLE on my 4K monitor. A high resolution monitor can make good experience better, and make bad experience even worse. Ugh.

And do I spot a solder bridge on the CY8C5868LTI on the KitProg section of the board? The manufacturing quality...
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Hello Shahriar,

I have been watching the video with lots of interest - thank you very much for the good work you are doing with your reviews and a special note for reviewing the FPH.

Actually, I also quite like R&S brand, despite its price point they do really good instruments. The video convinced me to acquire a FPH  :) I've been playing around with most of the features and like it!
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Repair / Re: Weird signal on oscilloscope
« Last post by PA0PBZ on Today at 01:16:22 AM »
How do you know the hard drive is ok, did you test it in a pc? Are you aware that a PC PSU can deliver in excess of 20A on the 12V rail?
Did you try to power up the hard drive using 12 and 5V from another source? Can you measure the current(s)?
Maybe the logic on the board is broken and it keeps powering up and down the drive?

Enough for now  :-/O
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Test Equipment / Re: Hameg 408-1A
« Last post by Specmaster on Today at 01:15:59 AM »
Double checked the resistors associated with the op-amps today which all checked out fine after lifting one leg from the pcb so I decided to remove the transistors for checking, T404 and 406 came out ok and passed testing, but the SMD ones are a different story, after using my hot air gun to remove T407 for testing, I promptly lost it when despite sticking it onto double sided tape to stop it escaping when probing with the test leads, it managed go flying into the ether, new ones on order...

Did not find any broken traces or bad solder joints anywhere as went round the board and checked traces point to point with my meter.

The +5v circuit all appears to be OK, diodes, caps and resistors, traces and sockets all checked OK.

I also tested for hotspots with an infra-red thermometer before removing the smps and all I found was a few IC's in places across the boards were warming up to mid 30C area, which is what I expect them to do anyway.

Had a response from Sky Messtechnic, they will respond with some schematics and tips / hints on what we need to check on Monday
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PGA2310/11 volume control
TPA6120A2 output amplifier
OPA1612 or OPA1622 anyewhere else required

The issue is not the signal chain. The issue is reasonably powering it (like, not 230V input, and no noisy DC-DC converters), and having a high quality source (AKA: USB DAC)
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Beginners / Re: Newb question - Single transistor oscilator
« Last post by kalel on Today at 01:14:03 AM »
That's a pretty great explanation of the circuit. Thank you both!
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If anyone have a simple open source board layout for them it would be nice ?

It's about $500, if not more, to print a minimum amount of 6-layer ENIG boards with 4mil traces (5mil might be Ok though) and 8mil drills. This will kill all the savings from buying your chips.
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What's the signal source?
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Projects, Designs, and Technical Stuff / Re: Bullshit Alarm
« Last post by The Soulman on Today at 01:11:07 AM »
From the wiki:
"PMPO[edit]
PMPO, which stands for Peak Music Power Output[22][23] or Peak momentary performance output,[24] is a much more dubious figure of merit, of interest more to advertising copy-writers than to consumers.[25] The term PMPO has never been defined in any standard,[26] but it is often taken to be the sum of some sort of peak power for each amplifier in a system. Different manufacturers use different definitions, so that the ratio of PMPO to continuous power output varies widely; it is not possible to convert from one to the other. Most amplifiers can sustain their PMPO for only a very short time, if at all; loudspeakers are not designed to withstand their stated PMPO for anything but a momentary peak without serious damage."

Yes PMPO can actually be easily calculated from the WLS rating: PMPO=WLS/4
So 6000 Watt WLS /4 = 1500 Watt PMPO/10 = 150 Watt RMS  :P
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