Background

Enoki would like to know indoor to outdoor range whether receiver elevation does effect.

Summary

The elevation effect is negligible, if the transmitter antenna is lower than the roof.

Building receiver in case with bar

Enoki built receiver and battery holder in 700 mL plastic case as shown in Photo1. The case was fixed with 0.9m woods bar.

Photo1 Receiver in box

Indoor to outdoor test

Riding a bicycle, Enoki monitored LED flashing on Arduino pro mini.

Enoki measured two directional range as the previous report.

Receiver antenna elevation
Enoki held up the receiver bar up and down at the limit of the ranges. The ranges unchanged, however.

Range is proportional to transmitter H and receiver root height h, if radio wave propagates like light.

Range ∝ (H^1/2 + h^1/2)
Range ∝ H^1/2(1+(h/H)^1/2)

When h/H is 1/2, 1/4 and 1/8, the above value in the bracket is 1.7, 1.5 and 1.4. In case of Enoki's transmitter antenna, it is lower than 1F ceil. The theory is meaningless.

enoki.net is surrounded by 2F houses. If transmitter antenna is installed on the roof, the theory might fit.

E32 433MHz 1W range is 8km nominal. By the above theory if the transmitter and receiver is the same 0.97 m high, the theory is satisfied. is it true?

Photo2 Southern range

Figure1 Southern range map

Photo2 and Photo3 shows to Enoki.net in the south and north. The ranges were as shown in Figure1 and Figure2. The measurement was by Google Map.

Battery dissipation
Enoki measured batteries voltage by DMM PC510 before and after the range tests.

Photo3 Northern range

Figure2 Northern range map

Table1 Battery dissipation - South

Bat	Start [V]	End [V]	Drop [V]
NiMH T	1.265	1.251	0.014
NiMH P	1.283	1.243	0.040
Time	07:09	07:52	43min

Table2 Battery dissipation - North

Bat	Start [V]	End [V]	Drop [V]
NiMH T	1.253	1.238	0.015
NiMH P	1.260	1.248	0.012
Time	10:08	10:42	34min

Table3 Range elongation

Direction	No bar [km]	With bar [km]	Ratio
South	0.77	1.44	1.87
North	0.67	1.18	1.76

Conclusion

Enoki doesn't know why the range of the receiver in box elongated almost twice. In case of the receiver in hand, Antenna coupling might change. Human fingers and palm seems to be a capacitor.

Ref

[1] Mitoshi kyori