Summary:

Technical team members went to the VE7EGO site to check RFI on the HF bands. A remote HF SDR receiver for club and public use had been proposed for the site earlier in the year but an RF survey was required to see if the site is quiet enough from the RFI perspective. Additionally, the new AC relay for the shack fan was properly protected by installing an electrical box extender and cover plate on the electrical box that houses it.

Attendees:

VA7SZ David
VE7JWS John
VE7KPZ Mike

Access:

The usual route was taken to access the VE7EGO Commonage site. Mike drove his Unimog with David as passenger and John drove his Jeep. Access track conditions were good with no snow although the temperature was below freezing.

Just before heading up to the VE7EGO site, Mike telephoned Kevin at 250-744-0732 who is in charge of exploding/disposing of WW2 munitions still in the hillsides. Upon departure from the site, Mike texted Kevin to notify him of our departure. Kevin likes to know both the ins and outs of our visits to the VE7EGO site. He prefers a call when inbound and a text when outbound.

Events Leading Up To The Visit

David was interested in installing a Kiwi SDR receiver at the EGO site for club and public use via the Internet. An RFI survey was required before proceeding further.

When the AC relay for the shack's fan control was installed earlier in the week, the size of the relay exceeded the size of the existing electrical box.

Actions Taken:

The team took Mike's end fed half wave (EFHW) antenna (HyEndFed Field Day) resonant for 80 (3.7M centre), 40, 20, 17, 15, 12 and 10 metres and strung it up between the back of Mike’s Unimog and a tree. The length of the antenna was 40 metres and it was approximately 4 metes above the ground sloping downhill from the EGO shack to the northwest. This was connected to Mike’s FT-891 transceiver after checking for a satisfactory SWR on the above bands with Mike's RigExpert AA-230 ZOOM antenna analyzer.

David then proceeded to scan each band and note the results. The S meter on the FT-891 was used to measure noise on 80, 40 and 20 metres.

Here are the results:

80M S7-8

40M S6-7

20M S5-6

David noted that some of the noise on 80 metres sounded like “crackle” from power lines, which is not entirely surprising because a BC Hydro line terminates at the site with a single transformer. There are six independent shacks at the site, which probably generate RFI from switching power supplies and other hardware. Unfortunately, these levels are rather high and an HF SDR would only deliver mediocre performance with this much noise.

While David was checking the HF noise levels, John and Mike proceeded to install an electrical box extension and box cover plate to completely protect the new AC relay which controls the shack's fan.

Next Steps:

None - the results of the RFI survey were discussed at the monthly club meeting later in the day and the consensus was that a more suitable site was needed before the project could proceed.

 

FYI,
David VA7SZ
NORAC Technical committee member

 

Ps: here are some pics from the trip:


John supervises David's HF site scan.


The HyEndFed Field Day antenna strung up from the corner of the Unimog's camper.
NORAC shack in the background.


The HyEndFed Field Day EFHW antenna is a full 40m long.
The other end is attached to the far tree.