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HF Beacons / Re: Coastal Slider Back On 4109.5
« on: September 06, 2023, 1825 UTC »
Greetings to all beacon aficionados!
In the rugged coastal mountains of California, a daring mission was undertaken last week to ensure the continued operation of a certain clandestine HF beacon known as the 'Coast Slider'. Join us as we recount this thrilling adventure up a misty mountain.
The journey began under the cool embrace of morning fog, creating an eerily quiet atmosphere. As our intrepid team ascended towards the beacon site, the persistent chill in the air was a most welcome companion. The sun eventually broke through the mist, but fortunately the temps remained pleasantly cool, setting the stage for an afternoon of repair and maintenance work.
Over the winter months, it became apparent that the Coast Slider's battery was no longer up to the task, struggling to hold a charge. This left the beacon operational only during daylight hours when the solar panel received sunlight. To address this issue, a comprehensive plan was hatched: replace the aging battery AND upgrade the solar panel.
Upon summiting the ridge, we were relieved to find the CS's container and solar panel in great condition - unmolested by human hands, vexatious varmints or curious condors. With great care, the box was unsealed and its contents eaxmined. To our delight, the battery and electronics were dry and pristine, untouched by the relentless rain of an unusually wet winter. This underscored the meticulous sealing of the box's lid and cable penetrations - care taken when the CS was first emplaced nearly 18 months ago.
Our first task was to replace the battery, installing a new 3Ah SLA to rejuvenate the transmitter. NExt, we turned our attention to the solar panel, upgrading it from its original 5 watts to a more robust 11 watts. These enhancements should ensure the the Coast Slider's uninterrupted operation for an extended period.
Replacing the panel meant cutting into what had been a continuous 10' underground run of cable to the beacon's container. This task was executed with precision, and the splice was carefully sealed to prevent moisture ingress, an important step in wet coastal conditions. (Oh, for a dry desert location with mostly sunny days!)
With the upgrades complete, time was spent to assess the beacon's performance. Its output power remained steady at 1/3 watt, a reassuring sign for its continued operation. However, the SWR had increased slightly to 1.8:1 (from 1.5), most likely due to the development of 2-3' sag of the antenna wire. And the resonant frequency also shifted down from 4110 kHz to 4060 kHz. The bungee cord which served to accomodate movement of the scrawny 'pine' trees supporting the antenna was replaced with a fresh bungee cord, this time enclosed in black nylon mesh tubing to protect it from the sun. The sag was left in the wire, since the antenna had survived a number of winter storms perhaps due to the slack.
The hike and maintenance tasks had far taken longer than anticipated (they always do!), so the elevated SWR issue was left for another time. The late afternoon sun cast long shadows as we started our descent.
Until the next adventure,
Beaconpop
In the rugged coastal mountains of California, a daring mission was undertaken last week to ensure the continued operation of a certain clandestine HF beacon known as the 'Coast Slider'. Join us as we recount this thrilling adventure up a misty mountain.
The journey began under the cool embrace of morning fog, creating an eerily quiet atmosphere. As our intrepid team ascended towards the beacon site, the persistent chill in the air was a most welcome companion. The sun eventually broke through the mist, but fortunately the temps remained pleasantly cool, setting the stage for an afternoon of repair and maintenance work.
Over the winter months, it became apparent that the Coast Slider's battery was no longer up to the task, struggling to hold a charge. This left the beacon operational only during daylight hours when the solar panel received sunlight. To address this issue, a comprehensive plan was hatched: replace the aging battery AND upgrade the solar panel.
Upon summiting the ridge, we were relieved to find the CS's container and solar panel in great condition - unmolested by human hands, vexatious varmints or curious condors. With great care, the box was unsealed and its contents eaxmined. To our delight, the battery and electronics were dry and pristine, untouched by the relentless rain of an unusually wet winter. This underscored the meticulous sealing of the box's lid and cable penetrations - care taken when the CS was first emplaced nearly 18 months ago.
Our first task was to replace the battery, installing a new 3Ah SLA to rejuvenate the transmitter. NExt, we turned our attention to the solar panel, upgrading it from its original 5 watts to a more robust 11 watts. These enhancements should ensure the the Coast Slider's uninterrupted operation for an extended period.
Replacing the panel meant cutting into what had been a continuous 10' underground run of cable to the beacon's container. This task was executed with precision, and the splice was carefully sealed to prevent moisture ingress, an important step in wet coastal conditions. (Oh, for a dry desert location with mostly sunny days!)
With the upgrades complete, time was spent to assess the beacon's performance. Its output power remained steady at 1/3 watt, a reassuring sign for its continued operation. However, the SWR had increased slightly to 1.8:1 (from 1.5), most likely due to the development of 2-3' sag of the antenna wire. And the resonant frequency also shifted down from 4110 kHz to 4060 kHz. The bungee cord which served to accomodate movement of the scrawny 'pine' trees supporting the antenna was replaced with a fresh bungee cord, this time enclosed in black nylon mesh tubing to protect it from the sun. The sag was left in the wire, since the antenna had survived a number of winter storms perhaps due to the slack.
The hike and maintenance tasks had far taken longer than anticipated (they always do!), so the elevated SWR issue was left for another time. The late afternoon sun cast long shadows as we started our descent.
Until the next adventure,
Beaconpop
