18. Screen Readability

Figure 96: Measuring Screen Readability

In order to test the 765T's screen brightness, I used a Mastech Digital 4-range luxmeter (LX1330B), capable of accurately measuring from 0 up to 200,000 lux. A luxmeter is used for checking the level of illuminance, defined as: 'the density of the luminous flux incident on a surface'. It is the quotient of the luminous flux by the area of the surface when the latter is uniformly illuminated. - (E = df / dA). This luxmeter has a rated accuracy of ±3% ±10 digits.

The nuvi 765T was placed in a controlled lighting area, inside a light tent illuminated by daylight balanced (5500° K) fluorescent lamps (the lamps are positioned on both sides of the GPS, as well as directly above it.

The luxmeter's sensor was held 1-inch away from the LCD display, with the light sensor horizontally facing the screen. The GPS was set to the Main Menu during the light reading, and the screen brightness was set to 100%. Measurements were taken three times, and the average was used.

In order to accurately compare screen readability between models, I have established Garmin's nuvi 660 as the baseline reference model. At the time of its release, the nuvi 660 sold for around $1,000, and was Garmin's most expensive automotive GPS at that time. The nuvi 660's LCD display was generally considered to have the best display of any GPS at that the. Other GPS displays may have come close, but none were better. In fact, the 660 at the time of its release was as close to a spare-no-expense GPS as had been seen.

The nuvi 765T's display measured almost identical brightness to the reference nuvi 660. The average reading for the nuvi 765T was 302, while the nuvi 660 scored 305 - a negligible difference that's within the margin of error for the luxmeter's rated accuracy.

In other words, the nuvi 765T has a bright, high contrast* display that's on par with the nuvi 660 reference display.

* The ability of a display designed into an electronic device to produce and maintain a viewable image with discernable differences between the lightest and darkest parts of the image when subjected to varying external and/or ambient lighting conditions.

19. Speaker Volume & Quality

Figure 97: Measuring Speaker Volume

Like most GPS units, the nuvi 765T has a rear-facing internal loudspeaker.

An Extech Type 2 digital sound level meter was used to measure the sound level at maximum volume. This type 2 sound level meter meets ANSI and IEC 651 Type 2 standards, and has a rated accuracy of ±1.5dB.

The sound meter was setup on a tripod spaced 12-inches (measured horizontally from the face of the LCD display to the tip of the sound meter) from the GPS.

The volume was set to maximum on each GPS tested, and the sound level meter was set to capture the peak level over a 2 minute period while the GPS simulated a route.

Although the nuvi 265WT registered slightly "louder" than the 765T, the speaker was tinny and distorted at maximum volume. The nuvi 765T wasn't quite as loud as the nuvi 660, and I did, at times, find it difficult to hear the GPS when driving at highway speeds.

More problematic is using the built-in speaker for handsfree speakerphone; the nuvi 765T's internal speaker isn't nearly loud enough to hear phone calls when driving around in the car.

20. Bluetooth & Hands Free Calling

Using Bluetooth, the nuvi 765T can be paired with a Bluetooth-enabled cell phone to become a hands-free device. Garmin has a website (garmin.com/bluetooth) where you can check if your phone is officially supported, although many phones that aren't officially supported will likely work as well.

Figure 98: Settings, Page 2

Before you can use the nuvi 765T's bluetooth features, the GPS must be "paired" by establishing a trusted relationship with a compatible cell phone. After the initial pairing, the nuvi will be able to connect to your cell phone automatically whenever it is within range.

To pair and connect, the Bluetooth device and nuvi must be within 10 meters of each other. The nuvi can be connected to a phone and a headset at the same time.

To begin the one-time pairing process, touch Main Menu > Tools > Settings > Scroll down to page 2 > Bluetooth

Figure 99: Bluetooth Page

Make sure your phone has Bluetooth turned on, and tap Add from the Bluetooth menu.

Figure 100: Set Your Phone To Discoverable Mode

Your phone must be set to discoverable in order for the nuvi 765T to find it.

Figure 101: Nearby Bluetooth Devices

After a brief scan for all Bluetooth discoverable devices within range (10 meters), the nuvi 765T displays a list of all found devices.

Figure 102: Passkey Information

When prompted, enter 1234 as the passkey on your phone. This Bluetooth security measure prevents unauthorized devices from connecting to your phone.

Figure 103: Successfully Paired

The nuvi and phone are now successfully paired. Note that you could have also initiated the Bluetooth pairing from your cell phone instead the nuvi.

Figure 104: Main Menu, With Phone Features

Once the nuvi 765T is paired with a phone, the Phone icon appears on the Main Menu. Touching this icon brings up the Phone page, where you can place phone calls, view your phone's address book, and more.

Figure 105: Map Page, With Phone Feature Enabled

The phone icon now also appears on the lower-right portion of the map.

Figure 106: Incoming Call

If a phone call is received while navigating to a destination, the Incoming Call alert is displayed, as shown above. Touch Ignore to send the call to voicemail and close the alert, or Answer to pickup the phone and user the GPS as a speakerphone.

The incoming call screen is accompanied by an audible ring tone that sound identical to the tone made when you place a call and hear the other end ringing. In other words, the incoming and outgoing ringing tone is identical. It's hard to miss the large pop-up screen that says there's an incoming call, but the ring tone is not loud enough, and sounds like you're placing a call instead of receiving one.

I was successfully able to pair two different Blackberry devices (8700 and 8820) without issue, as well as an Apple iPhone. The pairing process was smooth and worked without a hitch. The GPS can be paired with multiple phones, but only one phone can be actively connected at once.

A number of early Bluetooth issues have been addressed by a recent firmware update. Be sure to run Garmin's WebUpdater program and update the 765T firmware if you're having any dropped calls or difficulty pairing a cellphone.

I found overall Bluetooth performance was better on the 765T than on previous nuvi models. The annoying echo issue of earlier models is gone, probably thanks to the 765T's additional microphone intake on the front of the GPS (note that only ONE of the holes contains a microphone. The second hole is designed to reduce echo and improve audio pickup).

The 765T's internal speaker isn't nearly loud enough to hear a caller when driving in the car, so if you plan on making regular use of the Bluetooth hands-free calling capabilities, I'd recommend connecting a cassette tape adapter (like the kind made for using portable MP3 players in a car) to the nuvi's headphone jack, or buying a 3rd party FM transmitter that's better than the 765T's internal one.

Another option, if your vehicle supports it, is to use an audio input jack, or connect via Bluetooth directly to the car's audio system.