RobG 1,892 Posted September 6, 2011 Share Posted September 6, 2011 I agree with zborgerd, LS guy's answer is more about compliance than anything else. They just don't want people to mod their stuff. This module has to work with antennas from different manufacturers and it's the antenna that has to match, you don't have any trimmers on the module. Unlike in ham radio where matching is done on the transmitter side, matching in modules like that should be done on the antenna side. So why would they design PCB antenna that requires changes in the circuit? It just makes sense to adjust PCB antenna's dimensions and have a module design that is universal. In any case, there will never be a perfect match because antenna's environment will affect it's impedance. I think I am safe in assuming that this simple mod will do the trick. There's only one way to find out, mod one module and test it against the original one. Also, if you look at Microchip's modules mentioned above, the only difference between MRF24WB0MB and MRF24WB0MA is the position of capacitors. And here's a quote from cc2520's datasheet 9.7 Antenna ConsiderationsThe reference design contains two antenna options. As default, the SMA connector is connected to the balun through a 0? resistor. This resistor can be soldered off and rotated 90 GeekDoc and zborgerd 2 Quote Link to post Share on other sites
zborgerd 62 Posted September 6, 2011 Share Posted September 6, 2011 So why would they design PCB antenna that requires changes in the circuit? It just makes sense to adjust PCB antenna's dimensions and have a module design that is universal. Here's another question... Why put an antenna on a PCB at all when it can't be used? It's there so that they only have to fabricate a single PCB for all of their modules (a single footprint), and they simply have to add the appropriate parts when they fabricate the module. The matching network on the CC2591 is integrated. I cannot see how there could be any substantial differing components between the two modules. There are no resistors or caps on the PCB that cannot be identified and compared between the two boards. Besides... We have this: Reference Design: http://www.ti.com/tool/cc2520-cc2591em_rd Quote Link to post Share on other sites
zborgerd 62 Posted September 6, 2011 Share Posted September 6, 2011 The LS Research module has a Murata LDB182G4520C-110 Balun (50/200). So here's an even better reference design: http://www.ti.com/tool/cc2530-cc2591em-rd http://www.ti.com/litv/zip/swrc171 For all intents and purposes, the TI reference design in the CC2530-CC2591 Evaluation Module Kit appears to be identical to the RF portion of LS Research module. RobG 1 Quote Link to post Share on other sites
zborgerd 62 Posted September 6, 2011 Share Posted September 6, 2011 Regarding the antenna considerations, there are more details here: http://focus.ti.com/general/docs/litabs ... r=swra308a Page 19 points to two antenna design considerations: Antenna selection guide: http://focus.ti.com/general/docs/lit/ge ... er=SWRA161 Inverted F Antenna: http://focus.ti.com/general/docs/lit/ge ... er=SWRU120 Not sure that these were posted here, but I figured that I should bring them up so that we have them as a reference. Quote Link to post Share on other sites
RobG 1,892 Posted September 6, 2011 Share Posted September 6, 2011 I have mentioned SWRU120 (and SWRA117) before, but SWRA161 is a very interesting find. Thanks! Quote Link to post Share on other sites
zborgerd 62 Posted September 6, 2011 Share Posted September 6, 2011 I have mentioned SWRU120 (and SWRA117) before, but SWRA161 is a very interesting find. Thanks! Yeah. Lots of really good info in there. Quote Link to post Share on other sites
zborgerd 62 Posted September 6, 2011 Share Posted September 6, 2011 Just poking around, I've observed that LS Research appears to have a business model that involves the following: 1. Create modules that are "certified" in their labs. The owner of the company appears to have started a certification company in the 90's (per their homepage). 2. Modules have closed-source firmware. It looks like the files that they provide on their site are based on TI's Media Access Control stack 1.3.0. They give you the option to buy the source and design files if you wish to use their modules in your products, or you can buy the source and design files to use to create your own products. They will certify your modules for a fee. Quote Link to post Share on other sites
kenemon 29 Posted September 8, 2011 Author Share Posted September 8, 2011 Wow! all this discourse makes me want to get it going even more! Anyone mount it yet? I am waiting on the boards :think: Quote Link to post Share on other sites
4pyros 0 Posted December 18, 2011 Share Posted December 18, 2011 Thay still have 18 in stock at the Limited Offer price of $8.31. Has anyone tried theirs yet? the problume with the on board ant may be that it didn't pass regulatory tests, and this may also be why thay are selling them off. Andy Quote Link to post Share on other sites
kenemon 29 Posted December 30, 2011 Author Share Posted December 30, 2011 I am "actively" working on these babies. I managed to get the thing mounted and wired up using the "minimum" connections, which did not require any components besides LED's and 2 buttons. The firmware which is loaded, modflex, seems to work fine, but I have not been able to connect with my 2531 dongle.... yet. My efforts to load SimpliciTI have also been unsuccessful. I found a code for IAR which allows for larger code, but as with the CCS version, I cannot find the device when flashing. I will post more regarding this progress...... Thanks. KB Fri Dec 30, 2011 09:20:37: Interface dll version 2.4.8.2 Fri Dec 30, 2011 09:20:37: Invalid parameter(s) Fri Dec 30, 2011 09:20:41: Fatal error: Could not find device (or device not supported) Session aborted! Fri Dec 30, 2011 09:20:41: Failed to load debugee: C:\Users\Ken\Desktop\LSR Simplicity\480-0013-R0.2\SimpliciTI-IAR-1.1.1\Projects\Examples\SRF05_MSP\Simple_Peer_to_Peer\IAR\ProFLEX01\Exe\Simple_Peer_To_Peer.d43 Quote Link to post Share on other sites
kenemon 29 Posted January 6, 2012 Author Share Posted January 6, 2012 got some drivers swappped and i can flash again. still no ccs or iar.... Fri Jan 06, 2012 07:59:03: Interface dll version unknown Fri Jan 06, 2012 07:59:04: Device : MSP430F5437 Fri Jan 06, 2012 07:59:04: External voltage : 3.3 V Fri Jan 06, 2012 07:59:04: VCC voltage : 3.3 V Fri Jan 06, 2012 07:59:06: Fatal error: The Object file contains features not suported by the driver. Session aborted! Fri Jan 06, 2012 07:59:06: Failed to load debugee: C:\Users\Ken\Desktop\LSR Simplicity\480-0013-R0.2\SimpliciTI-IAR-1.1.1\Projects\Examples\SRF05_MSP\Simple_Peer_to_Peer\IAR\ProFLEX01\Exe\Simple_Peer_To_Peer.d43 Quote Link to post Share on other sites
kenemon 29 Posted January 9, 2012 Author Share Posted January 9, 2012 ANother "gift" from Arrow, for less than a penny: comes with two boards, batteries, cables, and CD get them while theyre hot, and try to help me program these. Cant get SimpliciTI workin with IAR. I am working on a CCS port. KB Quote Link to post Share on other sites
GeekDoc 226 Posted January 10, 2012 Share Posted January 10, 2012 Well, that was nice of them! Are they still available? Quote Link to post Share on other sites
kenemon 29 Posted January 10, 2012 Author Share Posted January 10, 2012 There are 4 kits there left now.... Quote Link to post Share on other sites
zeke 693 Posted January 10, 2012 Share Posted January 10, 2012 linky please Quote Link to post Share on other sites
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