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TI just emailed me about a promotion they are going to run in the coming weeks. Make sure you check their site and facebook pages.   Week 1: MSP430 LaunchPad - $6.99 Week 2: MSP-SA430-SUB1GHZ

Don't turn it on, take it apart:   http://flic.kr/s/aHsjHPrs1H (MSP-SA430)

It's available now http://e2e.ti.com/blogs_/b/msp430blog/archive/2013/08/25/back-to-school-sale-part-2-sa430.aspx   Coupon code SA_BTS

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Heh, for a simple comparison's sake, typing "spectrum analyzer 2.4ghz" into aliexpress.com I found this:

http://www.aliexpress.com/item/2-4GHz-USB-spectrum-analyzer-Cost-effective-Free-shipping-via-Express/795297115.html

$210 for a similar type of gadget.  So maybe its original price wasn't too far off the mark for this kind of thing, but $25 is great too ;)

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Don't turn it on, take it apart:

 

http://flic.kr/s/aHsjHPrs1H (MSP-SA430)

So, the JTAG is exposed and the UART is probably contained in the lines going to the TUSB.  That is a good start.

 

On another note, the noise on the SA430 seems high.  I build 433 MHz sensor tags and I have a lot of them in my office, which is small (maybe 100 square meters).  The noise floor in here is lower than -70dBm.  I have a SA430 and I have noticed mine also reports a high noise floor.  The CC430 RSSI is reliable to about -88 dBm in my experience, so there must be some noise on the board.  There are some long traces and switches to connect all the different baluns, so that must be where the noise comes from.

 

Why am I going-on about this?

I'm always looking for CC430 dev boards.  Knowing about the noise, I wouldn't recommend hacking this into a CC430 RF module.  PanStamp has a too-small ground plane, but if you use a dipole antenna instead of the monopole they seem to show in the pictures, it might be the best low-cost option.

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It is pretty fun hunting around and seeing some consistent humps in the graph... I found one around 780MHz or so, no idea what it is but it was very consistent.

 

edit: According to http://www.wpsantennas.com/cellular-frequency-information.aspx, 4G LTE Verizon is in the upper 700MHz band around 746-787MHz.  Wonder if that was it.

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More fun with SA430:  I'm trying to profile a new PIFA antenna I built despite working from home today.  The results are pretty darn good. I have my test device beaconing regularly.  It takes a little bit of time for the SA430 to perform enough sweeps of the spectrum in order to accumulate a decent plot.  But, there it is.  It took a minute or so, but my device isn't beaconing at a high rate (1 per second).

 

Perhaps a trained eye can tell this is GFSK on center channel 433.16 MHz, using +/-50 kHz subcarriers and data rate 55.5 kHz   :smile:  It is below ERC and FCC spurious emission limits, and the device antenna appears to have good efficiency.

 

post-13902-0-33252900-1377909173_thumb.jpg

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It is pretty fun hunting around and seeing some consistent humps in the graph... I found one around 780MHz or so, no idea what it is but it was very consistent.

 

edit: According to http://www.wpsantennas.com/cellular-frequency-information.aspx, 4G LTE Verizon is in the upper 700MHz band around 746-787MHz.  Wonder if that was it.

Likely VZW, as noted. AT&T LTE is 698-746 MHz- block B; VZW is block C.

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Hi guys,

 

Very interesting dissection. If you need different or wider frequency coverage there are a couple of other options. At the lowest price range you can simply get a DVB/TV dongle like this one https://www.cosycave.co.uk/product.php?id_product=282 and choose from a number of public domain software packages. 

 

I have one of these http://sdr-kits.net/VNWA3_Description.html which is very good for antenna analysis.

 

Hope this helps..

 

Steve

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I bought a Chronos earlier, thinking of playing with it, and now was thinking of buying two more with the idea being that myself, my wife and our nephew would each have one, and he'd be able to get some notification that we were at the school to pick him up and if he didn't get the notification he would go to the office without leaving school grounds.

 

However, there are issues with TI signing the drivers so they work on newer versions of Windows and I refuse to reboot just to work on something.

 

Am I being pedantic or trivial? Yes. But why should I, and many others, have to disable driver signing verification when all it takes is a little bit of effort from one TI dev to get around this?

 

I may buy a couple anyways, but it'll be under protest.

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