Search found 15 matches

by Dr T
Sat Aug 26, 2017 2:15 pm
Forum: The GAM
Topic: The Enduring Appeal of the classic 13-foot Boston Whaler
Replies: 4
Views: 263

Re: The Enduring Appeal of the classic 13-foot Boston Whaler

Newer and more expensive do not make a boat more valuable. The value of the 13 lies in its functionality, and it is this value that appeals to owners that could afford a much more expensive boat. If it ain't broke, don't fix it. And the worse comment I have had on my refurbished 82 about like Jefeci...
by Dr T
Thu Aug 03, 2017 7:16 pm
Forum: The GAM
Topic: Sport 13 Now Back on the Water
Replies: 10
Views: 405

Re: Sport 13 Now Back on the Water

I think that I will declare the shake down phase of my rebuilt Sport 13 as complete. There are a few tweaks left to do (transducer on the sonar, retightening of some screws, etc.), but it has now been shaken. Yesterday I was reminded of several things: The stability of the boat as a fishing platform...
by Dr T
Sun Jul 30, 2017 7:15 pm
Forum: The GAM
Topic: Advice to First-time Boat Owner
Replies: 34
Views: 2530

Re: Advice to First-time Boat Owner

One more simple suggestion: Unplug the trailer lights before backing down the ramp. I replaced far too many trailer light bulbs before getting in the habit.
by Dr T
Wed Jul 26, 2017 12:32 pm
Forum: SMALL BOAT ELECTRICAL
Topic: GPS Speedometers
Replies: 7
Views: 223

Re: GPS Speedometers

Just to beat the dead horse a bit more. The 0.4 mph resolution accuracy is related to two things: The 5 second update rate of most commercial devices and the 1 meter accuracy of GPS. In 5 seconds, at 0.4 mph you will move about 35.1 inches in 5 seconds, and 35.1 inches is pretty close to 1 meter (39...
by Dr T
Wed Jul 26, 2017 12:03 pm
Forum: SMALL BOAT ELECTRICAL
Topic: GPS Speedometers
Replies: 7
Views: 223

Re: GPS Speedometers

The plastic device using water pressure is called a pitot tube when it is used in an airplane and uses air pressure. Don't know if the terminology changes for maritime use. When you start looking at such small measurements, you are in Heisenbug territory: The increment that you want to measure is le...
by Dr T
Tue Jul 25, 2017 6:39 pm
Forum: The GAM
Topic: Sport 13 Now Back on the Water
Replies: 10
Views: 405

Re: Sport 13 Now Back on the Water

As an additional note, the Mercury prop selector tool using the inshore fishing hull type gets in the ball park. See
https://www.mercurymarine.com/en/us/pro ... #/step-one
by Dr T
Tue Jul 25, 2017 6:11 pm
Forum: SMALL BOAT ELECTRICAL
Topic: Effect of Antenna Height on Signal Strength
Replies: 4
Views: 1258

Re: Effect of Antenna Height on Signal Strength

After doing the stuff for several years in the days of my youth, I decided that once you considered every filter and amplifier as a noise-contributing operation in an inner product space, then simple linear algebra is about all you need. Even the power spectral density of a signal is just the norm o...
by Dr T
Tue Jul 25, 2017 5:48 pm
Forum: SMALL BOAT ELECTRICAL
Topic: GPS Speedometers
Replies: 7
Views: 223

Re: GPS Speedometers

I would only add that any sonar (fishfinder) with a GPS has a GPS speedometer. (Mine is a Hummingbird 788ci HD).
by Dr T
Tue Jul 25, 2017 5:42 pm
Forum: The GAM
Topic: Sport 13 Now Back on the Water
Replies: 10
Views: 405

Re: Sport 13 Now Back on the Water

It is a Mercury aluminum. I believe the model is called the Spitfire. It is about 12 inches in diameter. I don't have the part number. I described the performance I wanted and where I would be using it to the to the dealer, stated that I thought that a 11 pitch sounded about right, and left the sele...
by Dr T
Mon Jul 24, 2017 4:55 pm
Forum: The GAM
Topic: Advice to First-time Boat Owner
Replies: 34
Views: 2530

Re: Advice to First-time Boat Owner

Note: It is not enough to just have a boat plug. You also have to put it in. On the bright side, at least you are in a Whaler so it won't sink :-).
by Dr T
Mon Jul 24, 2017 4:46 pm
Forum: The GAM
Topic: Sport 13 Now Back on the Water
Replies: 10
Views: 405

Re: Sport 13 Now Back on the Water

When I picked it up, a guy at the marine dealer remarked, "When I looked at that boat for the first time, I thought that that is an awfully big motor for a little boat." It actually weighs only about 80 lbs more than the 35 hp Johnson 2-stroke it replaced (and it is about 20 or so lbs ligh...
by Dr T
Mon Jul 24, 2017 2:03 pm
Forum: SMALL BOAT ELECTRICAL
Topic: Effect of Antenna Height on Signal Strength
Replies: 4
Views: 1258

Re: Effect of Antenna Height on Signal Strength

Nice article, and a trip down memory lane. Back in the 80's and 90's when I was working on systems, we needed to worry about how close we would have to get in order to see something (context intentionally left blank). Since I was trained as a pure mathematician, I relied on our physicists and antenn...
by Dr T
Sun Jul 23, 2017 7:11 pm
Forum: The GAM
Topic: Sport 13 Now Back on the Water
Replies: 10
Views: 405

Re: Sport 13 Now Back on the Water

I misspoke when I referred to the battery as a "gel pad". It is a Cabela's Advanced Anglers size 22 battery with absorbed glass mats between the plates for isolation and vibration dampening. The technical description can be found at http://www.cabelas.com/custserv/custserv_popup.jsp?pageNa...
by Dr T
Fri Jul 21, 2017 9:20 pm
Forum: The GAM
Topic: 1969 13-footer with Center Console
Replies: 2
Views: 338

Re: 1969 13-footer with Center Console

Sounds like you have [a SOURPUSS model]

http://www.specialtymarine.com/BOSTON-W ... -p297.html
by Dr T
Thu Jul 20, 2017 9:35 pm
Forum: The GAM
Topic: Sport 13 Now Back on the Water
Replies: 10
Views: 405

Sport 13 Now Back on the Water

I acquired my 1982 Sport 13 back in 1987. It had a Johnson 35-HP with manual tilt and a 13-pitch propeller. I was using it on lakes in the Dallas area (at 600-feet elevation), and--on a good day--it might get all the way up to 26-MPH. It also took a while to get on plane. I moved to Colorado in 1996...