N7BHC/B Beacon in FM15

The N7BHC/B beacon is located in Oriental, North Carolina. Its primary purpose is to aid transatlantic troposheric ducting research.It is housed at the QTH of Chris, W4SLH. A special note of thanks and gratitude go out to Chris for her hospitality, and to Glenn N4LV for his local technical assistance.

Status: On the Air, fully operational

Beacon Details

Frequency: 144.291 MHz
Mode: CW, 13 wpm
Transmit sequence: N7BHC FM15PA N7BHC FM15PA N7BHC FM15PA <15 second carrier> <15 seconds receive period>
Latitude: 35.0302 N (35° 1' 49'' N)
Longitude: 76.7146 W (-76° 42' 52'' W)
Grid: FM15PA

Beacon Equipment:

The beacon is a "Simple Multifunction Beacon". It is based on a transceiver which can be used to work DX during a band opening if desired.

Transmitter: Kenwood TR-751A
Amplifier: Mirage B-3016G at 100 Watts output
Antenna: KLM 2M-16LBX at 45' agl, beaming 070º True, Horizontal polarization.
Feedline: 120' Andrew LDF4-50N 1/2" Heliax
Keyer: Hamgadgets ID-O-Matic
PSU: MFJ-4245MV

Reporting:

Send reports by email to "n7bhc at drasticom.net", or phone to +1 (704) 225-3928History. The first N7BHC beacon at this location first became active on July 18, 2008. The first beacon was the prototype for the Simple Multifunction Beacon. The first beacon used an existing military surplus case. An "advanced beacon" is under construction for this site which will permit full remote base opera tion as well as a multimode beacon. This first beacon was a quick solution to get a beacon signal on the air for the summer tropospheric ducting season of 2008. It also included rudimentary remote access for remote base operation in case of a band opening. The phone patch was manual operated

and would be initiated by a licensed operator on the site. A VOX was used as well for the remote operation. This mode was never used. The original beacon used an rfconcepts 2-315 amplifier which failed due to overheating despite being fan cooled and operated at reduced power. When the beacon was repaired in November 2008, it was upgraded to the standard rack-mount configuration. The amplifier was replaced with a Mirage B-3016G, the fuse replaced by a circuit breaker, and the phone patch and VOX removed. The picture to the right shows a standard simple multifunction beacon.The beacon in FM15PA is copied 24/7 at the N7BHC home QTH, a range of 223.4 miles (358 km). The receiving station at the home QTH is comprised of a 6 element WA5VJB Cheap Yagi in the attic, 50' of LMR-400, to the Advanced beacon under construction. That uses the preamp in the Mirage B-2530G amplifier and a TS-790A in narrow CW bandwidth. The computer running Spectran indicates signals received on every sequence. Note that this path is pretty much off the back of the 16 element yagi used on the beacon. Signal strengths run from a baseline at the noise level inaudible to the ear but easily seen on Spectran. More than 50% of sequences show aircraft scatter doppler shifted signals. Enhancement from aircraft scatter can be as much as 20 dB. Temperature inversion ducts can increase signals by more than 40 dB above nominal.

First Transatlantic reception of the N7BHC Beacon.

On August 9, the beacon was copied with partial data by CT1HZE. This is a range of 3,707 miles (5964 km). The exact propagation mechanism is not known, but it may have involved multiple modes. Tropospheric ducting was not predicted for the entire path by the Hepburn maps. However, CT1HZE reports a very str ong 6m opening at the time. Meteors from the Perseids meteor shower may have played some small role in enhancing in E-layer propagation. It is possible that coupling between tropo and E- layer for portions of the path occurred as well.. Here is the entire report from CT1HZE."At 1130 CT1HZE (IM 57NH) hrd CN8MC/B (IM63NX) on 50.027 MHZ with 599 on Es over only 412km. This is very unusual even in this region. For about 1 hour from 1130 to 1230 CU8DUB/B was audible at times for m inutes on Es then nil then 599 again and so on. There was a very widespread high MUF bubble over the Atlantic for a long time. CT1HZE wkd about 25 stations from Texas (W5) and one from California (W6) on 6m in the afternoon.Also loud pings from N7BHC/B FM15PA on 144.291 were heard at 18z from CT1HZE at the same time when N3DB (FM18SU) was 59+20 on 6m. Allthough a 100% sure identificat ion of the N7BHC beacon callsign on 2m was not successfull, unfortunately. Thus this will not be claimed “officially” as a transatlantic 2m reception."Future Beacon PlansThis beacon is slated to be replaced in the spring of 2009 with the N7BHC/B Advanced Capability Beacon. The antenna will also be replaced with a vertical stacked array of 5-element yagis designed by VE7BQH. The array will be 6-8 yagis tall by 1 wide, resulting in a wide horizontal beamwidth and a narrow vertical beamwidth.

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