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Project 4 - JYETech FG085

So, after many, many months of waiting, I finally got around to building the FG085 which was kindly donated to me by the excellent guys at JYETech. I can only apologise for the massive delay of nearly eight months between them sending the kit and my building it, but it's done finally, and working a treat!

I'm planning two video's for the FG085, the first of which is already available here, and also on YouTube. This first video covers the un-boxing and build segment, and the follow up will be a functional overview along with some example of how the device can be used.

I won't cover the un-boxing etc here as it's already included in the part 1 video, but I will say that the kit was well presented in a sturdy box, and everything was present and correct with no damage. Also, seeing as it came direct from China, the shipping was pretty quick to arrive in the UK, taking around 15 days.
The kit included a European style 2-pin 15v 1000mA power adapter, which after breaking it open for a looksie, is pretty much as expected in terms of quality. I always make a point of checking these prior to use, as I've had a couple of nasty surprises with cheap wall-wart type power supplies in the past, so don't leave anything to chance these days. This one is reasonably well constructed, although the soldering is pretty poor.
Its obviously an 'off the shelf' supply, and looking at the amount of unpopulated holes in the board, it is a general device which can be re-manufactured for different requirements. 

I'm pretty sure this supply isn't built by JYETech as it doesn't come anywhere near the quality of their kits, and I'm sure David Jones would be shuddering at the single self-tapping screw holding the thing together. 

Looking closely at the components, it seems that some of the components might even be second hand...there's a lot of dust inside for a new product! Also, there is an STP2NA60 N-Channel MOSFET which is showing clear signs of having been ripped out of something else and re-used. 

Whilst I don't have a problem with re-purposing and recycling of components, I do object when this production method is used in 'sold as new' products like this. As seen in the pictures, there is some isolation between the high/low sides of the board in the form of a spark-gap slot, which give some basic protection, and also they seem to be doing the right thing with the design by using a diode bridge rectifier on the AC side to smooth things out a bit.

I won't be leaving this plugged in all the time anyway - only when required for the FG to operate. Saying all this though, the device works, and meets safety standards, so I'll stop moaning. I certainly don't hold JYETech responsible for this supplies quality, as I'm almost certain they buy them in bulk as new - hopefully this post will encourage them to choose a little more carefully though as a duff PSU is a sure way to kill an otherwise excellent product and tarnish it's name just to save a few cents.

Also included is a basic BNC to Alligator clip test lead, and a single page showing assembly and basic operation of the FG085.

Here's part one of the video.

SS2 - JYETech FG085 miniDDS - part 1

So, it all went together in about an hour - the only thing that isn't obvious is the connection of the BNC to the main board - the tab on the spring washer is clearly not long enough to go through the slot below, so I broke it off and soldered a cut off component lead to it in order to make a good connection. This appears to be working fine. Also, the centre tap on the BNC plug doesn't quite make it all the way to the pad on the board below, so I used exactly the same method of filling the tap with solder and planting a cut off component leg in that too - this then allow a nice solid connection to the main board without stressing anything to 'make' it fit. If this isn't clear, review the video and you'll see what I mean. Everything else fitted perfectly and didn't require any modification. 

So, part two of this will come soon hopefully - my intention is to go over the device functionally, and show how it can be used in real world scenarios.