|Tout door[°C] / f[kHz]||10 m BCN
||4 m BCN||6 cm BCN GPSDO locked <2*10-10||3 cm BCN
GPSDO locked <2*10-10
|+20 °C||28 228.001||<1 min from start-up: GPS lock||<1 min from start-up: GPS lock|
|+15 °C||70 032.823||@ 5 min: +-6 Hz
@ 15 min: +-2Hz
|@ 5 min: +-10 Hz
@ 15 min: +-3 Hz
||70 032.784||5760 934.992
||10 368 935.040
Most recent measured "mark" QRGs underlined:
Try your DSP FFT display on these at great ranges!
OH5TEN&RBG Beacons' ODXes
|OH5TEN 10 m bcn: EA5OM 2965 km (40 spots/a)
||OH5TEN 6 cm bcn: OH2AXH 92 km|
|OH5TEN 3 cm bcn: OH2AXH 92 km|
|OH5RBG 4 m bcn: CT1HZE 3606 km (50
|Ham , BC & air frequencies in KP30:||Link to: Six and Ten Reporting Club|
|114.599 MHz 200 W ERP
UTTI VOR, AM CW ID: "UTT"+FM voice WX
105.700 MHz 30 kW ERP Radio Nova RDS: 6209 __NOVA__
102.700 MHz 30 kW ERP The Voice RDS: 62AB _VOICE__
99.500 MHz 30 kW ERP FSR Mix RDS: YLE_X3M_ YLE_VEGA
96.900 MHz 30 kW ERP YLE Radio Suomi 6203 YLESUOMI
92.800 MHz 30 kW ERP YLE X RDS: 6202 __YLEX__
88.500 MHz 30 kW ERP YLE Radio 1 RDS: 6201 YLE_YKSI
70.033 MHz 15 W ERP
28.228 MHz 4 W ERP
Send reception reports to DX-Summit
We also QSL (OH5TEN OH5RBG via OH5IY )
"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.
|10-2010->10-2015||28.228 MHz||50 MHz||70 MHz||432 MHz||1296 MHz||2320 MHz||5760 MHz||10368 MHz|
|TX Pout||+37 dBm,
|Refl. coeff, VSWR||pi (LC)-match||-26.5 dB,
1/1.37 or better
1/2.3 or better
|Pant, ERP||4 W,
This TX uses QRP2000 Si570 synthetizer followed by MMIC
amplifier stage driving RD16HHF1 10 W FET power amplifier. The
MMIC is CW keyed with a G4JNT keyer. With 1.4 dB cable
lossses and mid-line power splitter LC-match, some 4+4 W of RF is
fed to crossed dipoles for circular polarisation at 8 m AGL. The
ID "OH5TEN KP30HV" is send every 50 seconds and in between
30 seconds of carrier. Expected frequency stability is +-50
Hz annually. Si570 chip is thermally stabilized with QH40A heater.
Ambient temperature varies from +10 °C to +25 °C (winter/summer).
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.
5.7 GHz: GPSDO (108 MHz) indoors at room temperature,
drives ODU via LPF and 12 dB attenuator pad, an ERA-5SM MMIC stage
followed by 120 MHz BPF and is +Vcc CW keyed from G4JNT keyer.
14 V DC from 4 A SMPSU is fed to ODU via Lo coaxial cable via bias-Ts, ODU drawing about 1.11 A current at key-down. The mutiplier is a DB6NT kit (5.7 GHz modified link TX kit). 5.7 GHz PA is a commercial Walkera PA5801 Pout: 1.55 W.
Exact frequency of this beacon is 5760 934 992 Hz.
10 GHz: GPSDO (108 MHz) indoors at room temperature,
drives via LPF and 6 dB attenuator pad a +Vcc CW keyed (G4JNT
keyer) ERA-5SM MMIC stage, followed by 108 MHz BPF. The 14 V DC
power from shared SMPSU is fed to ODU via Lo coaxial cable with
ODU is drawing about 1 A current. Multiplier is a DB6NT kit (10 GHz BCN TX unit). 10 GHz 1 W GaAs-FET PA is from Dirk Fisher Elektronik. Exact frequency of this beacon is 10 368 935 040 Hz.
ODU electronics is build inside an ex. Allgon 900 MHz City GSM
base station panel, also enclosing two 1 m long home-made
waveguide slot antennas, one each for both bands. They are made
from std aluminium profiles, slots milled with Dremel-type hand
delivering horizontal polarisation, very flat beams, 13 dBd (5.7 GHz) and 16 dBd (10 GHz) 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, these beacons work better on rainscatter propagation, than on tropo. Except for the opening towards WSW, there is substantial treecover, but also some narrow gaps to S and SSW.
The 10 GHz coverage map is modified to account for the trees blocking the takeoff.
|OH5IY||measured Prx (@input)||Ga , line loss||hant|
|28.228 MHz @ QRB 10 m, GP||+7.5 dBm (6 m ant. 70°, V/UHF array: 130°) 08-2017
+6 dBm (6 m ant 210°. V/UHF array: 166°) 06-2018
|+0 dBd, 1.0 dB||9 m|
|28.228 MHz @ QRB 2.1 km 260.43 deg, dipole
||2017: -54.5 dBm H, -52.5 dBm V
2018: -47 dBm H, -49 dBm V (RF-Expl.) (V/UHF array QTF 180°)
|0 dB, 0.5 dB
|70 MHz , LPDA||-55.6 dBm 07-2016
-54 dBm 06-2018
|+2.5 dBd, 2.5 dB||10 m|
|5.76 GHz, 13 dBi horn||-43 dBm at 335 m az 226° (TX high tilt 5°)
-44 dBm 05-2017
-43 dBm 05-2018
|11 dBd, 0.5 dB||2 m|
|5.76 GHz, 13 dBi horn|| on Radome surface, top of radome=max power: +22.5
||11 dBd, 0.5 dB||NA|
|10 GHz, TV SAT LNB||+3.2 dBm at 335 m az 226° (TX low tilt 0.5° - just for the test)||+49 dBd (horn+LNB), -1 dB||2 m|
|10 GHz, TV SAT LNB||-17 dBm at 335 m az 226° (TX med. tilt 3.5° - first weeks)||+49 dBd (horn+LNB), -1 dB||2 m|
|10 GHz, TV SAT LNB||-25.7 dBm at 335 m az 226° (TX high
tilt 5° in use) 07-2016
-24.5 dBm 05-2017
-14.2 dBm 05-2018 (trees cut nr RX site)
|+49 dBd (horn+LNB), -1 dB||2 m|
OH5ADB received in KP30HV on 144.455 827 MHz with 19.7 dBd
antenna and 1.4 dB feed losses at -117 dBm.