Younger son has been down for a week during college half term and with a quiet week on the work front it seemed an ideal opportunity to tackle the work I wanted to do up the masts
Our VHF reception and transmission range on the masthead antenna has been rubbish since day one and I'd laid in a new Metz Manta whip antenna to replace the existing rigid glass fibre job (not, in my 'umble, a great choice for a masthead antenna on a yacht anyway)
Mark made the first of our several ascents up the main mast using my climbing gear. In the process, we made some further improvements to the rig which is now working really well. The only problem, common to all means of getting up the mast, is that it's difficult to get high enough to work right at the top. Indeed, due to his size, Mark simply couldn't reach high enough to get to grips with the old antenna.
My gear consists of a full body harness (actually a fall arrest harness) to which is attached a bosun's chair. The climbing line runs through an ascender with foot loops to a descender attached to the harness and then to a block clipped onto the ascender.
To ascend, you push the ascender up whilst bending your knees then stand up in the foot loops whilst pulling down on the free end of the line which, with your weight off it, runs freely through the descender . Then you sit back and the descender locks and you repeat the process.
To descend, the ascender and block are removed from the line and stowed in the gear pockets on the chair and you then abseil down on the descender
I also insist on rigging a fall arrester on a totally seperate halyard to the back of the harness. That runs freely up and down the line unless you fall at which point it locks and stops you hitting the deck with potentially fatal consequences
It's not actually that hard work to ascend once you get the technique right and it's about the safest possible setup available
So then I had a go ...
... and I had just enough reach to manage. Annoyingly, as I began to remove the old antenna from the stand off bracket, I discovered that the aluminium bracket was splitting and would fail at some point in the not too distant future.
Then I found that it was impossible to remove the screws securing it to the top plate! The only option was to hacksaw it off as flush as possible with the plate (the remains will be removed at some future date when we have the mast down)
Matters then became frustrating as for several days it was too windy to drill the mounting holes. It wasn't too uncomfortable up there but the mast head was vibrating and moving around in the wind.
There were other things to be getting on with though.
As well as the new VHF antenna on the main mast, I wanted to fit an AIS antenna on the mizzen (which will also double as a backup VHF antenna if the main antenna fails).
I decided it would be easier to lower the mizzen mast down and work on it on deck than climb it. There aren't the array of lines to use for climbing and fall arrest gear etc. on the mizzen. With the main halyard connected to the mizzen halyard and the mizzen forward shrouds removed, it proved relatively easy to lower it to the deck and then move it forward to gain access to the mast head.
With the mast down on deck, fitting the new antenna bracket was an easy job. We also, of course, had to run a coax cable down the mast.
Whilst we had it down, the squeaky halyard sheaves were liberally lubricated and I fitted a block and mousing line for a mizzen staysail halyard. We don't have a mizzen staysail yet but I intend to acquire one when I can!
We also removed the Dolphin vertical wind turbine for refurbishment or, if it isn't restorable, disposal.
Pagan looked rather odd as a sloop but she was soon restore to her two masted glory!
Hoisting the mast back up proved quite easy using the main mast halyard winch.
The new RAM3 remote mic for the new VHF needed fitting to the mizzen mast binnacle too.
This will give the helmsman full access to the VHF functions.
At the nav table, the existing VHF needed moving and the new VHF installing. Then all the various cables needed running in and connecting up.
Finally, yesterday morning presented a still, calm, day and I was able to fit the new bracket and antenna to the head of the main mast.
And then it was time to play with the toys ...
The existing M-Tech VHF has been retained as a backup and gets it's position fix from the chart plotter. In due course, it will probably get a dedicated rail mount antenna and it can also be attached to either of the mast head antennas at need
The new Standard Horizon GX-2000 has been mounted at a slight angle to make it more easily usable from the navigators seat position. It gets its position fix from the AIS transceiver
Mounting plates to store the Tack-Tick instrument heads have beeen fitted above the switch panels (the instruments normally mount on the rail above the hatch)
The charging stand for the hand held VHF has been screwed down to the corner of the nav table and various things moved around to better positions.
There are further changes to be made in due course in this setup - the switch panels are slated for replacement and the autohelm is also going to be upgraded later this winter.
With everything connected up and configured, I carried out VSWR checks on both new antennas. The mizzen AIS antenna is giving a very good VSWR of 1.5:1 but the main antenna is rather high at 2.8:1
That is almost certainly due to the length of the cable run, and maybe some deterioration of the existing cables, and at some point I'll replace the below deck cable with RG213, At twice the thickness of RG58, running RG213 down the mast in-situ would be a bit of a challenge so that will probably wait until we need to have the mast down
Despite the high VSWR reading, we are now reaching the coastguard loud and clear from our home berth, which we were not achieving before, and reception is dramatically improved.
Our AIS reception, previously very poor, is now astonishing ...
We're seeing everything out to 20 to 30 miles away no problem at all and picking up some vessels from as far as 70 or 80 miles away! That's not without it's downsides though. The more vessels the AIS transceiver can "see", the fewer transmission time slots are available to it. On the other hand, our AIS transmission range is now dramatically improved which means we should be visible on the tracking websites much of the time instead of intermittently.
Whereas previously we were not showing up on the tracking websites from Fambridge at all, now we are (via a shore station in Maldon)
All in all, an ultimately successful week. We didn't get as much done as I'd hoped but that's the way of it when working on boats!
Mark has, he assures me, enjoyed his week aboard Pagan and plans are afoot for Mark and Heather to join us next year for part of the Sojourn to the Solent
Our VHF reception and transmission range on the masthead antenna has been rubbish since day one and I'd laid in a new Metz Manta whip antenna to replace the existing rigid glass fibre job (not, in my 'umble, a great choice for a masthead antenna on a yacht anyway)
My gear consists of a full body harness (actually a fall arrest harness) to which is attached a bosun's chair. The climbing line runs through an ascender with foot loops to a descender attached to the harness and then to a block clipped onto the ascender.To ascend, you push the ascender up whilst bending your knees then stand up in the foot loops whilst pulling down on the free end of the line which, with your weight off it, runs freely through the descender . Then you sit back and the descender locks and you repeat the process.
To descend, the ascender and block are removed from the line and stowed in the gear pockets on the chair and you then abseil down on the descender
I also insist on rigging a fall arrester on a totally seperate halyard to the back of the harness. That runs freely up and down the line unless you fall at which point it locks and stops you hitting the deck with potentially fatal consequences
It's not actually that hard work to ascend once you get the technique right and it's about the safest possible setup available
So then I had a go ...
Then I found that it was impossible to remove the screws securing it to the top plate! The only option was to hacksaw it off as flush as possible with the plate (the remains will be removed at some future date when we have the mast down)
Matters then became frustrating as for several days it was too windy to drill the mounting holes. It wasn't too uncomfortable up there but the mast head was vibrating and moving around in the wind.
There were other things to be getting on with though.
As well as the new VHF antenna on the main mast, I wanted to fit an AIS antenna on the mizzen (which will also double as a backup VHF antenna if the main antenna fails).I decided it would be easier to lower the mizzen mast down and work on it on deck than climb it. There aren't the array of lines to use for climbing and fall arrest gear etc. on the mizzen. With the main halyard connected to the mizzen halyard and the mizzen forward shrouds removed, it proved relatively easy to lower it to the deck and then move it forward to gain access to the mast head.
With the mast down on deck, fitting the new antenna bracket was an easy job. We also, of course, had to run a coax cable down the mast.
Whilst we had it down, the squeaky halyard sheaves were liberally lubricated and I fitted a block and mousing line for a mizzen staysail halyard. We don't have a mizzen staysail yet but I intend to acquire one when I can!
We also removed the Dolphin vertical wind turbine for refurbishment or, if it isn't restorable, disposal.
Pagan looked rather odd as a sloop but she was soon restore to her two masted glory!Hoisting the mast back up proved quite easy using the main mast halyard winch.
The new RAM3 remote mic for the new VHF needed fitting to the mizzen mast binnacle too.
This will give the helmsman full access to the VHF functions.
At the nav table, the existing VHF needed moving and the new VHF installing. Then all the various cables needed running in and connecting up.
Finally, yesterday morning presented a still, calm, day and I was able to fit the new bracket and antenna to the head of the main mast.
And then it was time to play with the toys ...The existing M-Tech VHF has been retained as a backup and gets it's position fix from the chart plotter. In due course, it will probably get a dedicated rail mount antenna and it can also be attached to either of the mast head antennas at need
The new Standard Horizon GX-2000 has been mounted at a slight angle to make it more easily usable from the navigators seat position. It gets its position fix from the AIS transceiver
Mounting plates to store the Tack-Tick instrument heads have beeen fitted above the switch panels (the instruments normally mount on the rail above the hatch)
The charging stand for the hand held VHF has been screwed down to the corner of the nav table and various things moved around to better positions.
There are further changes to be made in due course in this setup - the switch panels are slated for replacement and the autohelm is also going to be upgraded later this winter.
With everything connected up and configured, I carried out VSWR checks on both new antennas. The mizzen AIS antenna is giving a very good VSWR of 1.5:1 but the main antenna is rather high at 2.8:1
That is almost certainly due to the length of the cable run, and maybe some deterioration of the existing cables, and at some point I'll replace the below deck cable with RG213, At twice the thickness of RG58, running RG213 down the mast in-situ would be a bit of a challenge so that will probably wait until we need to have the mast down
Despite the high VSWR reading, we are now reaching the coastguard loud and clear from our home berth, which we were not achieving before, and reception is dramatically improved.
Our AIS reception, previously very poor, is now astonishing ...
Whereas previously we were not showing up on the tracking websites from Fambridge at all, now we are (via a shore station in Maldon)
All in all, an ultimately successful week. We didn't get as much done as I'd hoped but that's the way of it when working on boats!
Mark has, he assures me, enjoyed his week aboard Pagan and plans are afoot for Mark and Heather to join us next year for part of the Sojourn to the Solent
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