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Gebrui nu de roker toets Druk rechts om op de pijltjes

(boven - echts - onder - links) en je komt in het volgende menu.

Ook voor niet rokers geschikt. :rolleyes:

Weetje ook dat met het eerst genoemde menu je de pix kan testen ( of deze allemaal het nog doen!!!). en de knoppen.

 

suc6 en pas op voor rode oortjes

 

Piet

En hoe testen we de pixels dan?

  • 4 weeks later...
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Wellicht een kleine waarschuwing m.b.t. de Diagnostic Screen(s) GPSMap 76CSx;

 

"...Enter - Hold the enter key down while powering up the unit will cause a test mode screen to appear. This test screen is used at Garmin in final testing and calibration of the unit. Warning! Do not use this screen if your unit can get a lock onto satellites. It is possible that a real satellite may spoof the test mode into recalibrating the unit with the wrong data. No permanent damage will be done but you may experience a little longer lockup times or may even have to do a total cold start to get it running again. You may also experience continued longer lockup times for awhile while the unit re-calibrates itself under use. You can read this document for a discussion of this issue from Garmin. If your unit has a removeable antenna then unplugging the antenna is a good way to ensure that no lock can be obtained.

The test mode screen can appear automatically if the unit detects a failure during power up. You can use this mode to verify certain operations of the unit. For example hitting each key will cause the corresponding key in the display to darken. Hitting the enter key twice in a row (on some units it is the page key) will cause a graphic pixel test which could highlight any bad pixels in your display. Hitting the same key again will further test the display. Hitting the key one more time will return to the main test screen. One units that use the page key to perform this test you can use the quit key to perform the graphic test backwards. The power/lamp key will show both an indication and actually light the lamp...."

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Het vervolgverhaal op mijn eerdere reactie:

 

"... WHAT HAPPENS WHEN YOU INADVERTENTLY

ERASE ALL DATA STORED IN THE GARMIN

 

Because of confusion and misinformation on the newsgroup, I have

asked Garmin Engineering to give us a consensus view of how the

accuracy and operation of the G-12XL (and other Garmin equipment

can be affected by operating the factory test mode while in view

of "real" satellites. In my view, the significance of the

"problem" is minimal since calibration points are automatically

restored when the unit is operated locked to SVs the next time(s).

The Garmin answer follows:

 

Joe Mehaffey

 

=================================================================

The answer from Garmin Engineering Follows:

 

Joe,

 

Some one did talk to Jay on the phone. I guess the answer was

not clear to him. What was said to Dr. Reid in the original

email to him (who altered it and then posted it (Garmin never

posted this information)) was that by operating the unit in test

mode, AND locking on to a specific satellite, you would destroy

the unit's oscillator compensation curve AT THE TEMPERATURE WHERE

THE LOCK OCCURS. Perhaps destroy is a bad word, it does sound

somewhat permanent. In fact, it WILL NOT damage the unit in any

way, but will erase the oscillator temperature calibration

point. It would appear that some have interpreted it as a

permanent degradation of the units performance. For that we

apologize. That is NOT correct.

 

Accuracy was never an issue. The only issue at stake is the

ability of the unit to lock on to satellites and calculate a

position.

 

As we know from GPS 101, A GPS receiver must be precisely

synchronized with the satellites to operate. We must know the

exact time the signal left the satellite, and the time the signal

arrived at the receiver, to calculate the time difference and

corresponding range to the satellite. By knowing the precise

location of the satellite when the signal left, and the range

(pseudorange), we know our exact distance from that satellite (at

that point in time). By performing this calculation on multiple

satellites, we can triangulate and calculate our position.

 

Obviously, timimg is everything. We must have a precise timing

source for this to work. We could install a rubidium or cesium

beam oscillator in our GPS receivers, but this would be a little

pricey, use a lot more battery power, and the unit would be a

little bulky. Instead, we use a relatively cheap oscillator, and

a lot of software finesse. Oscillator compensation data is

stored in the unit as a table based upon temperature. When the

unit locks on, it calculates the unit's oscillator error and

enters a correction factor into this table based upon current

internal temperature. In this fashion the unit is CONSTANTLY

"learning" and fine tuning itself. We burn these units in when

new to calculate and store calibration constants across the

entire rated temperature range of the product.

 

What Darrin and the previous Email tried to explain, perhaps in

different tones, was that running the GPS 12XL, or other GARMIN

units, in test mode, would mis-calibrate the units internal

oscillator if the unit locked onto the same satellite it expects

to see in the factory environment when connected to a signal

generator. The amount of mis-calibration depends on where this

particular satellite happens to be in the sky. If the satellite

is low on the horizon and heading directly towards or away from

you, there will be significant doppler shift on the signal which

in turn will grossly mis-calibrate our oscillator. This would be

worst-case and statistically rare.

 

The net effect of this type of mis-calibration may range from

long acquisition times to, on rare circumstances, failure to

acquire at all.

 

If the latter occurs, as Darrin pointed out, the user can put the

unit into Autolocate mode, which ignores oscillator calibration

and the unit will lock on and begin to repair the correction

table for each temperature it experiences. Of course, some users

might not know to put the unit into Autolocate mode, they may

see the unit not locking onto satellites and believe it to be

malfunctioning.

 

As soon as the unit locks on, oscillator calibration is performed

and peak accuracy is immediately restored. Of course, for

complete repair, the unit will need to be locked on to real

satellites for each temperature point that the unit was mis-

calibrated to.

 

Darrin and I do not disagree on any points. He was stating his

perspecive from a designers point of view, and I am giving you

mine from the standpoint that we don't want anyone to erase the

calibration from his unit.

 

GARMIN International

1200 E. 151st Street

Olathe, KS 66062 USA..."

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Ja, de Quest geeft inderdaad ook de informatie door 'on' en 'ok' tegelijkertijd in te drukken.

 

Ik neem aan dat de tijd achter 'Reset' de tijd is dat ik hem heb gebruikt?

 

Dat is dan nu: 1868:46 uur. (= dan ongeveer € 0,37 per uur / toenmalige aanschafprijs / september 2004) :)

 

f3be3ff9-04e0-4666-b83a-b761065257b4.jpg

bewerkt door Ringeling
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