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"Corrected" Tropospheric Path Loss = TX ERP [in dBm] + RX Ant. Gain [dB]  -  RX feed line loss [in dB, often negligible] - antenna height loss  [in dB, see graph below] -  -145 dBm [CW RX sensitivity level] - band noise above 290 K [in dB, from upper graph per  your location's man-made noise level]

It is expected your RX system Noise Figure is substantially below 3 dB! (RX k curve)

Using the calculated Corrected Tropospheric Path Loss value, you are able to determine the approximate maximum range (CW mode) from upper graph (signal received 50% of time).

Note: the "Corrected" Path loss here is used include effects that reduce RX S/N ratio specially on 50 and 28 MHz due to higher noise levels on those bands to get the true range and not just pure path loss. If you need only the path loss for shorter range to estimate signal level when S/N is not an issue, do not correct for band noise!

Note: Range can be reduced by lower TX and/or RX antenna's height,  terrain and other obstructions and by factors such as poor RX system Noise Figure, higher local noise level which to some degree can be corrected using the graphs.

OH5RBG's 70 MHz  beacon's ground wave coverage. Computed signal strengths (S-units) with 8.5 dBd RX antenna at 25 m above average ground level with unobstructed take-off, S 1 = 0.2 uV (-121 dBm) @ RX input.
 

The 70 MHz beacon was built during fall of 2009 with latest technology: USB-controlled synthesizer, PIC-based PC-configurable keyer and MMIC driving the FET PA. The basic scheme works for all bands from 28 to 70 MHz with just modifications to driver LPF and PA stage coils and capacitors - the single-ended FET PA is narrow-band type. Using the 175 MHz application sheet for RD06HVF1 FET, the beacon can be built for 144 MHz operation also. 432 MHz model would need different version for the synthesizer chip - the faster LVDS reaching up to 910 MHz.

The first built beacon module was for 40 MHz, but uncertain and troublesome licencing caused a rebuild to 70 MHz (took some 2 h) which has been a ham band in Finland since 4th Nov. 2009. The enclosure holds the 70 MHz beacon TX module with G4JNT keyer and a 4.5 A SMPSU. FET PA feeds some 5 W to a horizontally polarized low-gain (7 dBi) antenna (Aerial AV1462-70) beaming Az. 232° (SW for sporadic-E propagation) mounted on a cellular tower on a hilltop 131 m + 8 m ASL and delivering 15 W of ERP.

In detail, the synthesizer, which is configurable for any QRG from 3.5 to 260 MHz in 1 Hz steps (and for exact FSK shift) via the USB connection, delivers a 0 dBm (square wave) fed via 2- section LPF to ERA-5SM MMIC amplifier. G4JNT RS-232-configurable PIC-keyer keys the SDR-Kits USB-synthesizer. The +16 dBm drive feeds a low-cost SWR tolerant Mitsubishi PA FET delivering 5 W RF-output. The output is filtered with several LPF stages, one for UHF for added attenuation on cellular frequencies (harmonics are attenuated by 119 dBc on 900 MHz UMTS band). Total currrent is monitored with a 2 A analog panel meter. The antenna output circuit has a 230 V gas-disharge tube, 2 kV series capacitor and antenna connector & case bonded to site ground bar.

 The TX is the ex. commercial Multitone TA8 TX modified to FSK with G4JNT keyer.  With 1 dB cable lossses and mid-line LC-match (50 to 71-j20 ohms), some 4 W RF is fed to a slanted horizontal dipole at 9 m AGL with maximas to 250 deg. and 70 deg. and shallow side minimas not more than -13 dB and and a vertical dipole at 7 m AGL producing together circular polarisation since 24. June 2016 . The ID "OH5TEN KP30HV" is send  every 45 seconds and in between a 30 second carrier.  The frequency stability is unknow so far, but the XTAL has the QH40A heater bundled along with some thermal insulation. The ambient temperature varies from +20 C to +8 C annually.
 

OH5TEN's 28.228 MHz  beacon's ground wave coverage. Computed signal strengths (S-units) as received with a 6 dBd antenna at 25 m AGL.
 
 

CW keyed (G4JNT keyers) Si570 local oscillators (120 and 108 MHz) with QH40A heaters, are indoors at room temperature. The 12 V DC power from 4 A SMPSU is fed to ODU via Lo coaxial cables with bias-Ts, each ODU drawing about 1 A current. The mutipliers are from DB6NT kits (5.7 GHz modified link TX unit and a 10 GHz BCN TX unit). 5.7 GHz PA is commercial Walkera PA5801 and the 10 GHz PA is from Dirk Fisher Elektronik.

ODU is build in an ex. Allgon 900 MHz base station panel enclosing 1 m long home made waveguide slot antennas from std aluminium profiles milled with hand tools for each band, delivering horizontal polarisation, very flat beams and 13 dBd and 16 dBd of gain illuminating 100° wide sectors centered at WSW with 5° of up-tilt to climb over an adjacent hill and treetops there. Because of the tilt, the beacons works better on rainscatter propagation than on tropo. Except for the opening towards WSW, treecover is generally dense except for some narrow gaps to S and SSW. The 10 GHz coverage map is modified to account for the trees blocking the takeoff.

OH5ADB received in KP30HV on 144.455 827 MHz with 19.7 dBd antenna and 1.4 dB feed losses at -117 dBm.