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@@Rickta59 That's a nice deal. I have taken apart so many car chargers, you wonder how much it costs to make them :S

 

I just received the final components for a wireless sensor node project. Now I just have to finish my board layouts.

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Idea, create small solar powered node, use supercaps in place of batteries. I'm using some of TI's energy harvesters to perform MPPT to squeeze all the juice from these small panels.

 

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My Elecrow PCBs came in today. This is the 2nd version of a HP-25c emulation. The previous version I had 1 CR2032 to power the thing and it turn out not bright enough. I am multiplexing at 1/12 duty cycle (it has 12 digits). So this version I use 2 x CR2032 and a LDO.

 

This time I also overlay the button labels w/ an image (to print some of the scientific symbols) and they all failed to print. Not sure if it's the problem w/ Fritzing or Elecrow. The whole image (which contains some of the button labels) turn out to be 2 big dots, just below the top left button on the photo.

 

Not sure if I want to redo the PCBs. Don't want to waste these, may be I will hand write the button labels and use them as is.

 

post-23-0-00735200-1411096123_thumb.jpg

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@@simpleavr As it's black, could you get a reasonable silkscreen using the same toner transfer method that's used for home etching PCBs?

 

@@Fred that's a good idea for me to try. Even better if there are ways to overlay different colors. The HP calculator's shift functions are Yellow (F) and Blue (G). That would be really nice if can be done.

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It should be possible. The question is how the toner will react to the temperature when you're soldering. If I had a laser printer I'd have been tempted to try this myself.

 

It's a shame that white toner is so expensive and difficult to get as this would be even better for most silkscreen. (There are a couple of expensive lasers that do white but unfortunately it's not common enough for aftermarket stuff to be available.)

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@@dubnet @@yosh I saw that. It looks really interesting but I suspect it'll never actually get implanted. The size and location don't look ideal. However the real issue might be the silicone coating. The guy who fitted my implant was telling me about some issues with silicone coated neodymium magnets. Apparently with a bit of pressure the contents of the implant can rupture the silicone and it starts getting very nasty. What the guy should do is ensure that it will be possible to implant before going off designing something that'll never be used. I bet he won't though.

 

My much smaller xNT tag is apparently fine even in an MRI. I did have a minor operation recently which required a general anaesthetic and I was asked if I had any metalwork, etc. implanted. I got some odd looks when I told them about this, but obviously it wasn't a problem.

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@@Fred Yep, your implant is tiny compared to the device shown in that post. 5x2 cm is way to large for an implant which should be placed right under the skin. If you have ever seen e.g. cardioverter-defibrillators you know what I mean. I wouldn't want to have an implant that large in my arm (since you move your arm all the time).

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oh well, fwiw:     in my mail box today, not directly related to 430 stuff, but will be supported by 430 (read on)....

 

=======

Crystals :

=======

 

1-----      4.194304 MHz.  quantity 29.       in order to build some IF filters for a 30 meter band ham radio transceiver.

 

The LO is a super-vcxo based on standard 14.318 4x colour burst xtals.   (LO - IF =  10.124 MHz.  30m band 10.1-10.15)

MSP430 task -  control various aspects of the radio:  tuning/display/etc/ auto antenna tuner.

 

 

2----- 9.8304 MHz.   qty 20ish.        still indulging myself with hc811E  and hc11F1 (3MHz versions. so, 9600bps bootstrap mode).

 

Several projects with MSP430 overtones: I'll get the existing HC11s to become SPI slave devices to the MSP430 to do additional processing.   eg:

- inductance meter (shifted Fo technique)

- antenna swr / impedance

-- etc

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Besides the $20 watches that actually looks very nice, got my PCBs from DirtyPCBs. Normally for a panelized design, they cut and send me separate pieces, also they removed V-grooving from their capabilities a year ago, but this time they add V-groove to the boards! 

 

post-32777-0-65174500-1411971109_thumb.jpg

 

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Besides the $20 watches that actually looks very nice, got my PCBs from DirtyPCBs. Normally for a panelized design, they cut and send me separate pieces, also they removed V-grooving from their capabilities a year ago, but this time they add V-groove to the boards! 

 

attachicon.gifIMG_0049.JPG

Are those full-featured JTAG TagConnect adapters? Can you share some juicy details with us?

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Are those full-featured JTAG TagConnect adapters? Can you share some juicy details with us?

 

Sure, they're gonna be used as a substitute for an actual TagConnect TC2050 No Leg connector. Shops in Australia doesn't seem to stock these and shipping from the TC's website increases the total cost of 1 cable to $85, which is quite a bit much. 

 

I'm using pogo pins model P50-J1 from Aliexpress. The mounting holes of the actual TC2050 has a diameter of 0.991mm. It's very specific and I'm not sure where to get those from so for the time being, I'm getting 0.9mm carbide drill bits for now, which is very cheap in packs of 10 from eBay. If they don't fit into the footprint of a TC2050 snugly enough, maybe some taping would do. Two boards make up 1 adapter. They are stacked vertically to ensure the pins are straight. The two larger holes on the sides are for M3 10mm height standoffs. I shall post some details later if this works out fine.

 

PS: Just found out about these 0.99mm rods from eBay. :(

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@@rampadc That looks good. I was going to do something similar as they're hard to get in the UK too. Then bluehash managed to sort out some kits.

 

I wouldn't have thought that it would be too critical on the size of the mounting holes. Whilst your .9mm pins might rattle around a little in the holes for a standard TagConnect footprint, it should still line up well enough to give good contact.

 

You can my my home etched board for a TC2030 here which has holes that are drilled slightly too large. I had no problems connecting.

 

It might be worth reading through that whole thread. We had some confusion around TEST and TCK that wasn't helped by the FET documentation. This is possibly not relevant for the 10 pin TC2050. We also sort of decided between us to standardise on a modified TC2030 footprint that allows use of the TX/RX on the MSP-FET. (You might want to ignore that if you've decided to go with TC2050.)

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