MIRC point to M-point 900Mhz, Limited range, (unusable)

MIRMR2X_KIT Application- Greenhouse, distance between transmitter and receiver- <450 feet, remote antennas about 10’ above ground.
Not really an inside or outside application, basically a plastic tent. no walls, there is a plastic curtain between units.
There are 2" steel support posts about 22 feet apart in a grid supporting the structure. I described this on the old forum, asking if the antenna should be grounded, or mounted to plastic, and was told plastic. So the modules are completely isolated, (electrically via the power supplies, and from ground via PVC/plastic mounting).
With 2 channels activated, the transmitter flashes busy about once per second, ready light is on the rest of the time.
Receivers show ready most of the time, but will erratically flash busy, (with relay clicking and LED flashing) for less than a second from between 2 second to 20 second intervals. The correct relay is being activated. The relay never stays closed, even though the input is always on. Result is the same in beacon or smart mode.
I have very limited time to test / experiment with this stuff, (specially with forum based tech support) I will try metal antenna brackets later this morning and a bit of range testing.
------ Any suggestions, hopefully today, in time to actually try them?

Problem solved - nothing to do with antenna’s, c**py power supplies on the receiver boards.
Samkin brand, the specs were good, output was 12.2 Vdc, until the relay clicked in, then voltage went haywire. I think it also dropped when the receiver polled the transmitter. Supposedly 5 amp output - no way.

Hi Mike,

Glad you got that figured out. Please let us know if you have any other questions.

Thank you,
Travis Elliott