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All things pertaining to wireless and RF links
By collin
#185020
I have a two XBee pro 900hp 10Kb point-to-multipoint xbees.
I have each xbee connected to a separate computer through two parallax usb adaptor boards (32400, Rev C).

Whenever I send a frame from one device to the other through XCTU, the maximum RSSI on the received frame, is always -40db.
I thought the antennas might be the issue, so I swapped them out, but got the same results.
My next diagnosis was power. I tried sending the packets with different firmware assigned power levels, but again -40db was the best reported rssi.

I swapped out the 900hp modules with some series 1 (non-pro) modules.
I believe the series 1 modules have 1mw transmission power, vs the 900hp's 250mw tx power.

In XCTU I performed the same experiment as above. The RSSIs I saw had much better values. The best I saw was -26db.

Anyone have any advice?

For now, my next test is to hook up a volt meter to the power and ground pins of a 900hp module and see if there is a significant voltage drop upon transmission. my diagnosis from this behavior would be that I'm not supplying enough current to the module.
By stevech
#185052
Series 1 non-Pro 2.4GHZ are about 2mW but programmable as to power.
Series 1 Pro 2.4GHZ are up to 60mW.

900MHz are a totally different beast.