Casio 24 Time Zone Temperature Watch TS-100

CASIO ts100t I bought this watch about 23 years ago. It has 24 time zones. It measures temperature (either in 'on wrist' mode or in 'off wrist mode'). It stores the temperature every hour for the last 24 hours. It is reasonably accurate, and very handy to get an idea how cold it got when in the outdoors. My backlight bulb failed after 5 or 6 years. The waterproofing also went. Now if it gets wet, the battery needs to be replaced and the watch guts need to be dried out. I think the newer model doesn't have a light-bulb but an electroluminescent backlight. Module number is 815

Casio Gulfman DW-9700 I.C.E.R.C 1999

CASIO gulfman This watch is pretty rare. Mine is not a normal Gulfman, but rather a limited edition Gulfman called the I.C.E.R.C. All-As-One Dolphin & Whale. It is from the 8th International Dolphin & Whale Conference, 1999. It model name is DW-9700K, which is the same as the Gulfman. I bought it on the web from, a company in Malaysia. If you are looking for one, be sure it is a DW-9700, as there is another Dolphin & Whale watch. Casio also made several other limited edition Gulfmans, including one for the 1999 USLA National Lifeguard Championships (DW-9700UL-9T). It is really bright yellow and black. Mine is a much more subdued translucent gray, which I greatly prefer. The Lifeguard watch can likely be found on ebay, just search for Gulfman.

There is very little info on the web about this watch. Casio's web page sucks, but if you enter the 'module number' of 2017, you can get the owners manual. I was a bit leery of this watch, due to the serious problems I have had with other Casio watches, especially the Casio Titanium Pathfinder Watch. All my worries were groundless. I now believe that Casio knows how to make really good watches, even if they don't usually do so.

The Gulfman is a pretty complex watch, with many modes and sub-modes. It is a G-Shock watch, which means it is 200 meter water resistant as well as very shock resistant. It is one of the early solar powered Casio watches. The newer 2002 Casio solar watches are more sophisticated, since the solar panel is behind the display, rather than the Gulfman way, on the face of the watch where the display isn't. I have decided that solar power is pretty important for me, because all other Casio watches end up not being very waterproof after changing the battery. Solar power = not having to change the battery = really waterproof. I called Casio tech support, and they told me they had a really sophisticated way to seal Casio watches, which is how it is done when the watch is new, and that you can send back a watch and they will do it for you for around $10 - $12.

The Gulfman has a mineral crystal face. This is much more scratch resistant than a plastic face. The worst plastic face watch I know of is my Suunto Altimeter Watch , which is the watches worst feature. I think all serious watches need a mineral crystal or synthetic sapphire face. All the metal in the Gulfman is titanium. I have always lusted after a titanium watch, and now I have one. By 'all the metal', I really mean all. The watch case, the watch back, the watch back screws, the strap screws, the band buckle, the band retaining thingy, everything. You can see the details in the two pictures below.

The Gulfman displays the phase of the moon, and the tide. It can also display moon rise and setting times as well as sun rise and setting times. It can do this for 8 different locations, specified by latitude and longitude in one degree increments. The manual lists many locations, though the tide information for most isn't in the manual, though it can be found in other Casio manuals, i.e. module 2532. The Gulfman also has the usual stuff like 5 alarms, date, day of week, stopwatch, and the like.

One bad features are the nightlight has a picture of a whale or dolphin, which makes it hard to read. Another bad feature is the really tiny display of some data. You almost need a magnifying glass to read some of it. The owners manual is also quite unclear on a bunch of details.

Overall, I am pretty happy with the watch. The battery is almost certainly a rechargeable lithium ion, and should last for around 20 years. The watch is next to indestructible. It has all the features I really need. Perhaps one day Casio will sell a updated version of this watch, with a bigger, more readable display.

I ended up selling mine, as the display was too hard to read for my tastes.

gulfman top
gulfman bottom

Casio Gulfman DW-9700

dw9700 front About a week after I sold my I.C.E.R.C 1999 watch, I began to regret it. I could find no other watch with all of its features. Displaying all of the features wasn't very intuitive, and it was quite hard to read. I decided to get another DW-9700. The one I bought was a Japanese model DW-9700, module number 2080. It is all black, the backlight is plain (no dolphin picture to make it hard to read), and the band keeper is plastic unlike the I.C.E.R.C watch. I still wish Casio would make a newer version that was easier to read.

dw9700 back
dw9700 side

Casio Gulfman DW-9700 Helly Hansen 2000

dw9700 front I also bought a Helly Hansen DW-9700, which is from the Nippon Challenge America's Cup 2000. The band is off-white. It is in very good condition, and looks new.

dw9700hh back

OVO Decision Maker Watch

OVO Decsion Maker I read about the Decision Maker on in someone's list of essential electronic gear. Having a soft spot for digital watches, I was intrigued by it. I bought it from TokyoFlash, sellers of unusual watches.

Even though the picture of the watch I found was white, the actual watch was a turquoise blue. What was not clear from the description or the picture, was the watch was designed for a very small wrist, like a child's. The strap attached at an angle to the watch itself, so on my wrist, the watch stood out a ways from my wrist. Also the strap was very small. I recall it fit on the last one or two holes in the strap.

It did work as advertised, which was very amusing. Sometimes you had to shake it to get it to not shake the display. It beeped. It flashed lights. It is made by Takara Corp who made that weird electronic pet toy that was very popular in Japan. If it wasn't for the band, I would have likely kept it. It also wore out its battery in about 5 months. Fortunately, there is ebay. Someone in Italy saw it, and I shipped it to them.

Since it isn't generally available anymore, I will include a description:

Ever had a hard time deciding which direction to go, or should I, or shouldn't I? Well this watch will do the deciding for you. It is equipped with several functions that can point you in the right direction or make decisions for you. 3 LED lights flash on the side when functions are selected and all kinds of beeps and screen savers are displayed. I have personally played with this watch for almost 2 hours and there are still new displays coming up. Push both buttons at the same time when in time mode and the time display goes all wacky in un-countless ways. The numbers blur, shake across the screen, go up and down like waves. It has a virus scan, ram, CPU, memory screen displays. I think I will stop here and let you find out the rest for yourself. The sound can be turned off too, so you won't irritate everyone around you.

The Decision Maker Watch by OVO "boots" up and pretends to be a full featured PC, scans for viri, RAM, etc.. but it's actually a watch that just helps you make decisions.

Why we like it: Not only will it answer your deepest most important YES/NO questions with a spin of the dial and flashing LEDs, it will also tell you which direction to go if you're lost.

OVO Ana Digi Watch

OVO Ana Digi I bought the original Decision Maker watch. It was too small for me, but otherwise very cute. I was looking at TokyoFlash and saw the OVO Ana Digi watch. I asked them if they had a copy of the owners manual they could send me (which they didn't). I asked them if it was for larger wrists than the Decision Maker (which they didn't know). It looked like an interesting watch (and they sent me a discount coupon) so I decided to buy it.

It is much more sedate looking than the Decision Maker. It actually fits my wrist quite well. It would be nice if the band was a bit bigger, but I can secure the strap. The strap is black rubber and integrated into the watch, so it cannot be replaced. The watch doesn't have any flashing LED's, nor does it make a bunch of silly sounds. It doesn't even have shake sensors, or weird screens (anti-virus, memory scan, etc.) like the Decision Maker does.

It does have a decent backlight, which the Decision Maker lacked. It has analog hands as well as a digital display (which can be turned off). It has a timer, 2 alarms, a chronograph, world time and a decision maker function. I am not sure how many cities are listed with world time, but I would guess more than 20. I don't even recognize the name of some of the cities. The decision maker function is much more sedate than the Decision Maker watch, and just gives advice. You can even set the time to 24 hour mode (which I like).

The watch does use two batteries, one for the analog watch and one for the digital watch. Hopefully the batteries will last a reasonably long time. For me, this one is a keeper.

Timex Datalink Iron-man Watch

Timex Ironman Datalink I bought this watch when I wanted to go white water rafting and all my waterproof watches were too expensive to risk in the river. It stores around 50 names and phone numbers. It also does laps and the usual watch things. It is reasonably inexpensive, had a very good light, has a excellent reflective LCD that is easy to read during a full moon, and has very high contrast during the day. It is also reasonably waterproof. The worst feature is it is only programmable with windows 95 or 98. It doesn't work with windows NT or 2000 (unless you get a silly serial port led toy which costs about as much as the watch.) I contacted Timex, and they claim that their software simply cannot be made to work with windows NT or 2000. They have some newer Datalink watches which do work with NT and 2000, so I think the folks I spoke to were clueless or misinformed.

The new datalink has an USB connection. In addition to being a watch, it acts as a personal organizer. It can hold hundreds of phone numbers, appointments, notes, and the like. If my Ironman-datalink ever fails (unlikely) I will get this one. Both the Ironman datalink model that I have and the Ironman datalink USB have flown in space. The common space watches are the omega X-33, omega speedmaster, and Casio g-shock.

Timex Datalink Ironman USB Watch

Timex Ironman Datalink USB I had wanted this watch for a while, I got it for a good price. It has a USB connector to communicate with the computer. I got the version with the rubber watch band, and it is a bit on the small side, fitting on the next to last hole for my wrist. The bezel around the glass isn't as substantial as the older Ironman datalink, but seems to do a decent job of preventing scratching. The screen is quite readable, perhaps even better than my old data link. Much more readable than any Casio watch that I have seen. The watch band also seems to be very nicely made. The 'keeper' for the band has an oval hole which mates with an oval bump at the end of the band to securely hold the end of the band. The clasp has 5 holes drilled in it for unknown reasons, but it looks nice. One problem is the backlight. It can be disabled, or enabled during certain times (auto mode). If it is enabled during certain times, it will turn on when ever you press a button, that is there is no specific light button. If you enter a dark theater and want to see the time, you will have to switch from auto mode, to on mode (which can be done), but I would prefer a dedicated button. Perhaps this was done to minimize the number of buttons. Both the Ironman datalink model that I have and the Ironman datalink USB have flown in space. The common space watches are the omega X-33, omega speedmaster, and Casio g-shock.

I loaded the world time program which is very nice, as well as a bunch of contacts (names and phone numbers). I also loaded a program called My Watch which has a wide variety of watch displays, and is highly recommended. There is supposed to be some tide displaying program that I am looking for for the data link usb. There are a few things that could be improved however. The glass front could be mineral crystal or some other scratch resistant material. The watch could be solar powered. It could be more programmable. The backlight could have a different user interface. The plastic watch band isn't very durable. I have broken two of them. I have switched to the metal and plastic band instead. Hopefully it will be more durable.

Timex Datalink Ironman USB Metal Band

Timex Ironman Datalink USB band outside Timex Ironman Datalink USB band inside

Well, my metal watch band broke. More specifically, one of the small black rubber links in the metal band broke. i decided to order another band or two from Timex. I called them, and they said they don't sell the bands anymore. They had some rubber bands, but ran out a few months ago. They have been out of the metal bands for about a year. I asked if they had another watch band that was compatible with the USB datalink and they said no. Well, I was in a tough spot. The part of the band that is next to the watch has a unique end. It sorta looks like a W, and there a reverse W on the watch. I could an aftermarket band, but there would be two gaps on either side of the watch body, and would look quite odd.

I decided I would repair the broken band. I thought about gluing the broken piece of ribber, but I would likely get glue on several moving parts of the band. I thought about substituting a metal clip for the rubber part, but I decided it would be difficult to find metal of the right dimensions and bend it to secure it. Then I decided I could use solid copper wire. I got some 22 gauge copper wiring. I removed the broken rubber link. I wound the copper wire between the two metal rods embedded in the watch band, where the rubber link went. I used four or five loops. I cut off the ends on the side away from my wrist, so they wouldn't dig into my wrist. I then soldered the wire on the outside to secure it and add some stiffness and strength. In making the copper loops, I made them a little tighter than the rubber link, but the band still is flexible where my copper link is. It isn't perfect, but is is quite serviceable.

Well, two more black rubber links broke. I repaired them the same way I repaired the first broken link. I suspect eventually there will be more soldered copper wire on the band than black rubber links. It would be nice if the rubber were more durable or if timex still made bands for the watch. I may have to get a nylon webbing band though it would look pretty ugly - at least it would be durable and hassle free.

Well, four more black rubber links broke in the last 24 hours. I repatied them. For the first time, two links on the same row broke, causing the watch to fall off. In the worst case, I could lose the watch if this happens. I suspect in time most of the links will fail. I have now replaced 8 out of 22 of the links.

Well, two more blank rubber links broke today. I repaied them. Another link went. Finally, today one of the links that attaches the rubber end with the rest of the watch band failed. There is no way to replace it. After repairing 11 links, it is now time for an aftermarket watch band. It will be ugly, but should be much more reliable than the Timex bands have proven to be.

Garmin Epix 2 Pro Sapphire smartwatch

This is the most expensive watch I have ever bought. It is a sports smartwatch. Garmin is a GPS company that also makes watches. The GPS receiver will receive all the major navigation satellites, and is also multi-band. It has a long life while the GPS is enabled. It is very well made.

I have found a number of issues however. First, you install an app on your smartphone, called Garmin connect. Next you install another app called Garmin connect IQ. No idea why you need 2 apps. I downloaded a 'watch face', as the faces included with the watch were not very nice for me. It queued the download, but it wouldn't download. The watch seemed to have the new face, the app said pending. There was nothing I could do to push the download. Finally, I rebooted the phone, and the download showed that it completed. Poor software.

You can customize the included Garmin watch faces. I tried, but the user interface to do it was a bit confusing. Also the navigation to get to the point where I could customize the watch face was quite confusing. Perhaps with more experience, it would be less confusing, but I think it is a poor user interface.

One reason I bought the watch was the pulse oximeter feature. In 1996, I worked on what became the best oximeter company in the world, so I have some understanding of pulse oximeters. I enabled it, and it said if it was always on, then the battery would drain faster. I enabled it anyway. I was having a hard time getting a reading. It said not to move for about 30 seconds. Eventually I got a reading of 93. Now I know this isn't a medical instrument. Still, in 1996, we had technology to deal with motion artifacts. It seems Garmin doesn't. I had assumed I could get readings while hiking or running. I guess not. Another issue is the reading. Based on my experience, I would say my typical reading would be 98 or 99. Getting a number of 93 shows the quality of the measurement is poor. When developing the oximeter in 1996, I had a perfusion of about 5%. This is a really strong signal. The oximeter would get accurate readings with a perfusion below 0.1%. So the signal strength shouldn't be an issue for Garmin. There is a lawsuit in the works between Masimo and Apple for pulse oximeter technology. The International Trade Commission found against Apple, and so Apple has removed the pulse oximeter functionality from their current watches. It would seems that Apple wanted really good oximeter technology, unlike Garmin. There was a lawsuit, which resulted in a hung jury. I might accept the crappy oximeter on a cheap watch, but the Epix is a very expensive watch.

Garmin sent me email asking me to review the watch. I did that on May-27-2024. On Jun-04-2024 I got an email from Garmin saying "Write a Review and Share Your Feedback" So what happened to the review that I did on May-27? Did they lose it? Did they not like it and delete it? Either way, it seems very odd to ask me to review the same watch twice. Best case, Garmin is simply clueless.

Zeblaze Stratos 3 smartwatch

This is a very inexpensive smartwatch, with a lot of features. It turns out it is very inexpensive for a reason. For all the watches I have, I get the owners manual and I keep it on my computer. The owners manual for this watch (or any other Zeblaze watch as far as I can tell) is not available online. The paper copy has really tiny print. This is not unique to Zeblaze, as many Casio manuals have really small print. Unlike Zeblaze, Casio manuals are available online. Also, there is no contact info for Zeblaze that I could find. Most other watch companies have online contact info. There are some YouTube unboxing videos for the watch, but there are no real watch reviews of people actually using the watch. Also there are no other reviews of any other kind that I could find on the internet. These were warning signs, but didn't stop me from buying the watch, unfortunately.

The watch looks ok, with a very bright screen. The band is made of a nice, flexible material. Unfortunately it is a bit on the small side. I have only had a watch with too small a band once, and that was on a novelty watch that was likely designed for children.

There are two cell phone apps. One is called Strava. It seems to be some kind of a site to track performance and post information publicly. They ask many questions during the sign up process. They have support for many smartwatches, but not for any Zeblaze watches as far as I can tell. When you try to check all supported devices, it shows a screen that doesn't list smartwatches. The other app is for the Zeblaze watch. The only useful setting I could perform with that app was to select always on heart rate monitoring. I was expecting a wide variety of settings, but no such luck. I was unable to configure the watch, as it quickly timed out. I couldn't find the setting to set the time out interval. Without that, I couldn't configure other settings. There were some icons, but they quickly blanked out. Having the settings be controllable via the app would be a good idea. Having a setup process for the watch on the watch would be a good idea. Having the default timeout be a bit longer would be a good idea. The watch is supposed to have multi GPS capability and a lot of other stuff that I was unable to verify. The heart rate did seem to bounce around a bit, before the screen blanked. I returned the watch, as it was unusable.

Well, even thought I returned the watch, I have gotten 3 additional emails saying they are waiting for my return. I replied to the latest one, saying that the watch has arrived at their agent (all of which is tractable). I also said I am disappointed that they haven't realized I returned the watch a week ago, and that I will be disputing the charge if I am not promptly refunded. This is the first item I have returned something from aliexpress, and though the process seems simple, it isn't. Just another thing to keep in mind.

Avocet Altimeter Watch - For Sale

Avocet The Avocet watch was the first reasonably accurate altimeter. It sure is bulky and ugly though. A bad feature is it is rated to about 10 feet of water resistance. Probably ok in the rain, but that is about it. It has an anti-hysteresis feature which makes it very accurate when accumulating altitude gained while hiking. The battery life isn't great, and Avocet wants to change batteries and recalibrate the watch. When I bought the watch, it cost $5 to send the watch to Avocet. Then they raised it to $10, and last time I checked, it was $20, which is unreasonable. There is a circuit layout bug in the first generation watch which makes the displayed temperature read high when it is very cold. I put mine in a calibrated -40F, and it read -16F.

What is worse, is the band design. There is a elastic 'ski' band, which is useless for me. There is a nylon webbing one, and a rubber strap one. I used to have the nylon webbing one, but when I was in Fairbanks Alaska, the plastic clasp that held the nylon webbing shattered in the cold temperatures of around -25F. The good news is that I called Avocet on their toll free number, and there was a new rubber strap waiting for me when I got home. I sent them the shattered plastic clasp...

My watch is now for sale. If anyone wants it, it is in good condition, it just needs a battery.

Casio Generic Altimeter Watches

I have owned at least 2 Casio watches that measure altitude. Since I teach navigation, altitude is a handy feature. The first one also had a water depth gauge which I found a novel toy. As for the altimeter, last time I checked it was very temperature sensitive. According to the Casio manuals the displayed altitude varies 100 meters with a 10 degree C change. This makes it unsuitable for any kind of serious navigation.

Casio Titanium Pathfinder Watch

CASIO prt 700nt I think the watch was model PRT700NT-7AV. The Casio watch has many features. It measures altitude, barometric pressure, and temperature. Here are some specs:

The Barometer (range 13.55inHg to 32.45 inHg, display unit 0.05 inHg) takes barometric pressure readings every 2 hours and stores up to 10 sets of readings with the altitude and temperature in memory. The Thermometer (range 14F to 140F, display unit 0.2) checks the temperature once every 5 minutes. The Altimeter (range -2300 ft to 19,680 ft., 20 ft. increments) takes altitude readings every 2 minutes, displays them and stores them in memory. With the Auto Light Switch on, simply tilting your wrist 40 degrees toward you from the horizontal position illuminates the EL backlight for about 2 seconds. Analog and digital timekeeping. 12/24 hour formats. 1/100 second stopwatch. Hourly time signal. Daily alarm. Countdown timer. 100M water resistant.

Sounds pretty groovy, right? Well, there is some titanium. The back of the watch case is stainless steel. Much of the front of the watch is black plastic. Worse, the interface between the watch and the band is black plastic. There is the conventional pin between the watch and the plastic thingy, then another pin connecting the plastic thingy to the titanium band. The clasp of the band is conventional, with a secondary clasp to hold the clasp shut.

Now for the problems. There are two models, one of which has a backlight for the entire watch face, and another with a backlight only for the two small LCD displays. I got the second one, not realizing there were two different models, which is pretty useless. I am used to the Timex backlight, and found the Casio one very dim.

What is worse, is that under normal use, I had the primary clasp of the band open. The band didn't come off, but it might have. Also under normal use, the pin between the watch and the cheapo plastic thingy connecting to the band opened. This made the watch fall off. This is completely unacceptable, as a watch that falls off is pretty useless for outdoor use.

Also unclear until I bought the watch is that the 10 readings the watch stores must be taken manually, not automatically. The readings every 5 minutes for temperature are not stored anywhere. Check the owners manual before buying a Casio watch.

Suunto Core Altimeter Watch


This is a very large watch. The case and bands are available in different styles. Mine is an inexpensive style, all black with a nice black rubber strap. It is comfortable to wear. Like the Vector, it features an altimeter, barometer, compass. In addition, it has a depth gauge that goes to 10 meters. The battery compartment lid is stainless steel, not plastic. The display face is mineral crystal, not plastic, making it much more scratch resistant. Some have complained that the display lacks contrast. No idea why, as it is very high contrast and easy to read. I presume the altimeter is as accurate as the Vector. It has menus to set all of the options of the watch, which makes it easy to navigate all of the options.

After about a year, the watch band keeper broke. Suunto sent me two. Over time, they broke also. I called them, and they had me send in a picture of the watch. They are sending me more, and they say these are improved and more robust.

The display went blank. The battery was drained. I put a new battery in, but the display stayed blank. I measured the battery at about 3v, so that wasn't the problem. I called Suunto support, and they explained the RMA process. I filled out a web form, and it produced a prepaid shipping label. The hardest part was finding the serial number, which is really tiny and on the back of the watch (the plastic part). Hopefully Suunto can fix it. I can't remember the last time I had an electronic watch fail.

Turns out there was a thin plastic flap that was keeping the battery from making proper contact. Suunto found it in one day, and it is being shipped back to me at no charge. They are awesome, and I shoulda seen the plastic flap.

Well, the watch has failed. The display went blank. I replaced the battery and after a month, it went blank again. It seems that pressing the backlight button, causes the screen to blank, and then the watch resets. When I pressed it again, the screen went blank, and stayed that way. I sent it back to Suunto, and after a few weeks, they emailed me saying the watch failed the pressure test. No details. Perhaps toe o-ring failed, perhaps not. They didn't see if the backlight has a short or anything like that. I asked them to send to send it back to me. It will cost about $27 for the diagnostic and shipping. They offered to sell me a new watch for about $170. The problem is I can buy a new watch for $109 or so. It would be nice if they offered me a bigger discount, but they say they can't do that. I am currently using my Suunto Vector (which doesn't have a backlight).

Suunto Suunto

I decided to replace my broken Suunto Core. I bought some watches on ebay. The first was a core with an orange band and the inner bezel being aluminum. The second was the newer Suunto Core All Black. In this watch, the bezel has 2 markings for north, and hourly markings around the inner bezel. Though the markings are of a high visibility yellow, they do not glow in the dark, and are just high contrast paint. Additionally, the display has a black background and the numbers are white. The watch is supposed to have a 'military' style. The display is readable, though not as readable as the original core with the positive display. Also of note is the All Black bezel is made out of what looks to be painted aluminum. The surface is easy to scratch, and the entire perimeter of my used watch is worn down to the bare metal. I suspect the original core has a plastic composite bezel, but I have not scratched it to verify that.

Suunto Vector Altimeter Watch


This is a great altimeter. It is also reasonably waterproof and has an easy to change battery. Just be sure to use a nickel on the battery compartment lid, or you will cause it serious harm. I have the one with the plastic face with the leveling bubble. The bubble is cute, but the plastic scratches very easily. It sure is a large watch. I recommend the glass faced versions.

Like most outdoors companies, Suunto has excellent customer service. When I broke the band they sent me a new one. When I stripped the battery compartment lid they sent me a new one (use a nickel to open it). They didn't want any money for either problem, which were my fault. I still haven't figured out what to do with the rotating bezel for the compass... This is probably the best altimeter watch available (though I am unfamiliar with the Avocet II).

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