ELAD DUO ART REPAIR

If you’re a frequent visitor, you’ll know I like a bargain and I’ve managed to bag a few over the last few years. The last one was a dead Micro PA-100 Amp which I bought for peanuts and then fixed it for a few more peanuts. So when I spotted this £1300 Elad Duo Art for very little money, I couldn’t resist, despite my spidey-senses tingling like crazy (spidey-sense is an extrasensory, near-precognitive awareness of impending danger) 😂.

Well, to cut a long story short, it was super cheap because it had a serious fault - there was no power output on the 40M band! In all fairness though, it worked perfectly in every other respects including the built-in ATU. When I attempted to use 40M, I could immediately detect that dreaded burning component smell 🔥 Oh dear! 😥

I contacted the amazingly helpful Vianney at ELAD and described the problem. He  responded very quickly with a useful schematic and some advice on what the problem might be and gave some recommended specs for replacement capacitors. Thank you Vianney 🙏🙏🙏

I’ve highlighted the area affected

I delayed tackling the job for quite a while because, in all honesty, I was scared to dismantle the Duo Art. It looked quite complicated and I could easily end up with a useless electronic jigsaw! 

Anyway, for some reason I decided that today was the day to grow a pair of ball$ and dive in! I removed the top cover and saw that there were basically 3 boards and I had to deal with two of them. Looking at all the electrical and SMA connectors, I felt a little overwhelmed, but carried on regardless. 

I started off by taking as many photos as possible to aid reassembly and then started to snip all the cable-ties. Then it was a case of removing the various screws holding the boards in place. 

Once I had removed the smaller top pcb (the ATU), I could see a metal shield which also needed to be removed. 

You have to be careful with this because it has a set of cables taped along its edge. In the end, rather than removing it completely, I managed to slide it to one side.

With that (awkward) bit out of the way, I could see the RF Filter board and after careful examination, I could see no signs of burned components or any other damage. The damage was obviously on the other side of the board 🙄 which meant more stripping down, so out came the camera again. To remove this (large) board, you have to undo the three DB-9 sockets from the chassis’s backplate and then carefully manoeuvre it out. 

Straight away I could see the damage on the underside! It didn’t look pretty, but apart from the thought of removing and replacing those incredibly tiny SMD caps, I was really worried that the tracks on the PCB might be damaged too!

I felt that I would really be stretching my luck by tackling this repair myself, so I contacted a friend in Scotland to ask if I could post the PCB to him for repair. I'm waiting to hear back from him, but if he isn't able to help, I think I'll just have a go myself. I've found the 1206 caps on Farnell's website. They're 1000V instead of 630V, but I'm guessing that doesn't matter.

I'll update this page soon, with a big smile or floods of tears, LOL.

73, Tom, M7MCQ.