M/V Discovery Tech Notes

Mexican Nautical Charts – this is getting fun

2011-09-25T08:27:00.001-07:00

We’ve always been interested in nautical charts and in particular, electronic charts. When we first came to Mexico we had Maptech charts on the PC running Coastal Explorer (CE) and C-Map charts on Furuno. Both are based on surveys done around 1890. That’s right, over a hundred years old. Here’s an example of these charts in CE -

If you click on the image to enlarge it, you can see that our waypoints where we anchored are up on land with this chart and there is a dreadful lack of detail.

Fortunately the Mexican Navy has been doing a new survey since 2005, using borrowed US equipment they say, and have published new vector charts that while not up to the standards of US NOAA charts, are a substantial improvement over the older charts. Here’s the same area using the new vector charts -

At least the land is in the right spot. Now we can add a third type of chart to the collection, charts from Google Earth satellite images. I’ve started playing with a program ChartAid that makes it very easy to capture images from Google Earth and geo-reference them so that chart plotting software like CE knows where to place them. Here’s the same spot with the addition of the photo chart -

These Google Earth photo’s are not perfect, they don’t show depth for example, but outside of the US, Canada, and Europe they might be a great improvement over existing charts. They certainly enhance areas in Mexico. Will we rely exclusively on photo charts? No, but they are another tool, along with existing charts and guide books, that we can use to stay out of trouble.

Icom 802 Upgrades

2011-01-01T13:53:00.001-08:00

Over the summer we did some changes to our SSB installation trying to improve the radio's reception and transmission and reduce radio frequency interference (RFI).

Here's a summary of what we did -

Installed 6/2 AWG wire from house bank to pilothouse for use by the HF and primary VHF radios, we have 2 fixed mounted VHF radios. This removed some of the RFI but not all. One of our depth sounders still causes a chirping sound but the hum from the pilothouse 12 vdc refrigerator is gone.

Installed a TG Electric N8XJK Boost Regulator - see here
This item claims to perform two tasks; 1) outputs up to 15 vdc from any DC input down to 9 v and 2) Eliminate RFI and cleans up your power source. It does a good job on #1 but not so much on #2. I set the output at 14 volts which it maintains no matter the state of charge of the house batteries but I have not heard a lot of RFI reduction.

CLRspkr DSP radio - West Mountain Radio - see here
This is a replacement speaker for the Icom 802 radio which has built in digital signal processing, DSP, to reduce background noise and static. It uses a process where it converts the analog audio signal to digital and then filters out any repeating noise, such as static, but not voice. The filter is adjustable from none to max in 4 increments and it works great! This unit turns receptions of signals that are difficult to understand to near clear. But I have had 2 problems with this product. The first unit I bought at the Ham Store in San Diego went dead after about one hour of use. I then exchanged it for a new unit just one day before we left on the boat to cruise south and the second unit has the volume 'clipping' indicator light on when ever there is sound present. It seems to work all right in reducing static but if I were in the States I'd return it. Returning items from Mexico to the US is very difficult and problematic so we will wait until next summer and try to return it then.

Our solar panel controller, a Blue Sky 2000E, was creating a constant click, click, ... static on all frequencies and after discussing this on the SSCA forum, the best place for info and advise on marine communications and solar panels I have found, we decided to replace the 2000E controller with a Blue Sky 2512ix controller. Many people reported very little or no RFI with this model. The 2512ix will also be a better model for us in the long run because we plan on adding 2 more panels next year and we'll be able to network the 2512ix controller with another 2512ix and a central control panel located in the pilothouse. The 2512ix model does seem to have less RFI noise in our case and we feel it was a good change.

Combined, these changes have improved the RX and TX of our Icom 802 a great deal. The dedicated power line actually delivers less voltage to the radio, about 2/10 of a volt less than the voltage at the panel but I'm assuming that it's cleaner power. The Boost Regulator then ups the voltage to 14 volts which makes the 802 transmit better. The 802 is very sensitive to voltage under 12.8 volts so it's a good thing to add a power booster. The best change was adding the DSP speaker. DSP audio processors are common and built into many new Ham radios but the CLRSpkr is nice because it builds the DSP circuits into the speaker case so you don't have to contend with another box.

We also discovered that the Danfoss compressors in our refrigerator and freezer cause noise on the 8 meg frequencies which happens to be where the Southbound net is located, 8122.0. We have started turning off the frig and freezer at the panel before the net along with our depth sounder and we have been very happy with the clarity of the reception. So far we have not forgotten to turn the refrigeration units back on, knock on wood.

I also reprogrammed the 802 to is a more logical frequency layout to my mind. I have not been happy with the channel layout design from when I first got the radio and I finally found an internet site that sold the programming software and interface cable. I reprogrammed it to match Gordon West's latest "full load" program layout. I did make a couple of small changes to Gordon's layout because of the Net's in this area but it is a much more logical layout to me.

I also got my Ham General license over the summer taking the Tech and General exams in San Diego. The exams were not easy for me but I did pass both exams on the first attempt and it was an enjoyable experience. We can now participate on the Sonrisa net which is a Ham only net.

Frank

Ok, this got too hot.

2009-09-16T14:17:00.001-07:00

This is the shore side end of our power cable that we used to power our air conditioning. It has obliviously gotten way too hot. The receptacle that it was plugged into was old and worn out and destroyed both of them. I had to cut back 10' of cable before I found clean wire that was not heat damaged.

Good Vector Charts for Mexico

2009-08-21T08:57:00.001-07:00

I finally have found some electronic charts of Mexico that are at least of 'good' quality. The MapTech electronic raster charts of Mexico are unusable outside of the major port areas. The C-Map that our Furuno chartplotter use are better than MapTech but not that good. We have use Coastal Explorer for our PC Chartplotter for many years and when we upgraded to their latest version they noticed that they added the capability to use Navionics S-57 vector from ChartWorld in Germany. These charts have special copy protection and are referred to as S-63 format. In the US, NOAA distributes all of the marine charts for free so the ChartWorld charts are only for areas outside the US. After some research and concern that these vector charts would not be any better than the old raster charts I finally purchased the set of charts for western Mexico. The cost is EURO 150, about $213 dollars US. Coastal Explorer has worked with ChartWorld to make the install process easy. I did have a little problem with the install because I had changed the chart directory settings but CE support was very helpful in sorting it out. The difference between the raster and vector charts are amazing, see photo's (Vector on left, old Rasters on the right). I've read that the Mexican Navy has done a new survey of Mexican waters in the last few years and it's that survey that these charts are based on.
I don't know what other software supports the ChartWorld vector charts but if you are going to Mexico these charts are worth getting a copy of Coastal Explorer 2009 for just to be able to use these charts.

Links -
ChartWorld GmbH
Coastal Explorer 2009

Solar Panels

2009-08-14T13:25:00.000-07:00

Today we finished adding solar panels to Discovery. We bought 2 Kyocera KTM 130 panels and a Blue Sky 2000E Controller. Discovery has a dinghy davit where we store the dinghy except for ocean passages and the top rails of the davit are a natural place for the solar panels. We ran the 6/2 gauge wire inside the davit upright tube into the lazarette and then into the engine room where the controller is located. At anchor we use 300 to 320 amps per day and we hope to get at least 100 amps from the panels which will reduce our generator run time by an hour or more. We purchased the panels and controller from Northern Arizona Wind & Sun

Links - Northern Arizona Wind & Sun

Boat Wire - GenuineDealz.com

DVD Hack

2009-08-12T14:13:00.000-07:00

We have been renting DVD's from the Blockbusters in Guaymas since we got here, we just requested a card and they quickly provided one with few questions. This is our 3rd country that we have a Blockbusters card for; 1)US, 2)Canada, and 3)Mexico. Most of the DVD's play without a problem, all you need to do is select Inglés (English) as the language and/or turn off subtitles. On two occasions we got an error that said 'Wrong Region'. Not having a clue what this meant I did a Google search and it seems that DVD producers can encode what region of the world (US, Europe, Latin America, etc.) they want the DVD to play in and the player has a region code embedded in it when it's manufactured. If your DVD has a region code and it doesn't match your player's region code it won't work. Fortunately there is a way around this for some DVD players. Our player is a cheap Cyberhome brand but I found a undocumented hack for changing the region code on the player. Once I did that it would play all the DVD's we rented. Isn't the internet great!

Link - VideoHelp.com

Shade Tent

2009-08-12T13:56:00.000-07:00

Last winter when we were in the West Marine in San Diego near Shelter Island, Linda found a shade tarp made for a sail boat to hang over the boom that had a small tear in it and was on sale for nearly 50% off. She felt confident that we could make it work to cover the bow of the boat so we bought it and she was right. It looks like it was made for the boat and in fact some people have said that they thought it was a custom made cover. It covers the bow and provides shade for the entire front stateroom and the shape allows us to open the hatches to let air in but protects us from the rare rain shower.

New VHF & SSB Antennas

2009-08-12T13:50:00.000-07:00

When we bought our boat it had the original 15 year old 23' VHF and SSB antennas mounted on the pilothouse roof. When we did an update of the electronics in the winter of '08-'09 we added a second VHF with a Digital Antenna 8dB 6' antenna. On our trip south down the Pacific coast the 23' antennas took a beating and the VHF reception through the 23' antenna degraded greatly to the point that it only received nearby broadcasts. The antenna had obliviously had saltwater intrusion and needed to be replaced. While we were at it I also wanted to replace the matching SSB antenna. Both antennas are Shakespeare brand and 15 years old so I wanted to replace them with the best antennas I could find. After doing some investigation, isn't the internet great, and asking on some forums I decided on Morad brand antennas out of Seattle. Being from the Seattle area I was familiar with Morad, they are made from a distinctive gold anodized aluminum tube and are easily spotted on boats. Most commercial fishing boats in the PNW and Alaska use Morad as does the US Coast Guard.

I contacted Morad directly and after exchanging emails with the owner Ken Holland we decided on the configuration that would best fit our needs and he custom made the antennas with custom milled bases to run the coax out the side and be able to screw into the hinged roof top base. These are not the cheapest antennas on the market but for about 50% more than a Shakespeare they are truly a quality product that is far superior to the cheap fiberglass antennas on the market. Here's what we got -

VHF-156 HD "Hot Rod" HD Style VHF 6dB Gain
9130 WH-23G-UPS SSB Unloaded 23' Whip Antenna, Gold - UPS Shippable
9130 WH-23G-UPS SSB Unloaded 23' Whip Antenna, Gold - UPS Shippable WITHOUT FIBERGLASS TIP
999 8" ALUMINUM ADAPTOR - CUSTOM MADE
1203 RG-213 Coaxial Cable 35'

The 9130 SSB antenna without tip is used as a base for the VHF-156 HD antenna. We haven't been out of the marina since installing the antennas so I haven't been able to give them a good test but I'm very impressed with the initial results.

Link - Morad Electronics

Is This Too Hot?

2009-06-30T08:17:00.001-07:00

I spent the day obsessing about the temperature of the shore power cables. The shore power cables on our boat have a rather clever configuration. The boat has two 50 amp connectors and our slip has two 30 amp plugs so we have run two cables to the dock with two shore cables that have been configured with 50 amp plugs on the boat end and 30 amp plugs on the dock side so we don't have to have conversion cables and the additional connections. With two shore power cable connected we can select on the service panel to have the Air Conditioners (A/C) to be dedicated to cable #2 so that the A/C and only the A/C runs off of that connection. All other 120 VAC loads are on cable #1. On the dock the 30 amp plugs are in the deck box, one facing out and a second that was added later is inside the box. Both have 30 amp breakers.

We have three Air Systems units on the boat: 1) Model VRP16K (16K btu) in the main salon, 2) Model CMP12K in the Pilothouse, and 3) Model CMP 12K down below with ducts to the Main and Center staterooms. With the two 12K A/C running the #2 cable plug at the dock is at 104° to 107°F. This is with an ambient air temp of 92° F. Cable #1 has a temp of 101° F.

I've switched the function of the cables so the A/C cable is connected outside the box with similar reading so being inside the box does not cause the temperature of the plug to increase. Running all three A/C will raise the temp of the plug to 112° F. My concern is this too hot?

I inspected the plugs and there is no sign of overheating, no discoloration or burn marks. We have not thrown a breaker on the dock in the three weeks we've been here even when we have all three A/C on and running the washing machine, a Splendine 2001.

We'll be watching this closely to make sure that we don't burn the plug or cable during the summer. If we lose a shore power cable we'll be in trouble trying to run the A/C's and during the summer the A/C is not a luxury, it's a necessity.

New Blog

2009-06-29T16:25:00.000-07:00

Welcome, this new blog is a partner to our M/V Discovery Travel Log Blog. In this blog I will discuss technical issues and projects that we undertake on the boat. As with all full time cruising boats, maintenance is a full time job so there should plenty of fodder for this blog.