Home PageFacebookRSS News Feed
Pocket GPS World - SatNavs | GPS | Speed Cameras: Forums

Pocket GPS World :: View topic - Garmin cfQue 1620
 Forum FAQForum FAQ   SearchSearch   UsergroupsUsergroups   ProfileProfile   Log in for private messagesLog in for private messages   Log inLog in 

Garmin cfQue 1620

Post new topic   Reply to topic    Pocket GPS World Forum Index -> Advanced GPS Lounge
View previous topic :: View next topic  
Author Message
Occasional Visitor

Joined: Jun 19, 2004
Posts: 1

PostPosted: Sat Jun 19, 2004 4:09 am    Post subject: Garmin cfQue 1620 Reply with quote

I am a long time user of Garmin products and have (until now) thought of them as the top of the line GPS company. Ever since I first heard that they were coming out with a CF GPS and software for the PPC, I have been looking forward to it. As soon as they started shipping, I ordered one. I have had it now for about ten days and am very disappointed with it. I have been in contact with Garmin tech support and as usual these days I know more about the system than the tech support guy. My cfQue installed on my Toshiba e755 with no problems and acquired satellite lockons. The problem was that it appeared to me that the reception was a bit weak and sluggish. I compared it with a Garmin GPS III Plus that I've had since they first came out. The III Plus had acquired nine satellites and had a solid 3D lock while the cfQue only had two sats and no lock. Mind you I had the two well separated to avoid and EMI problems. I queried Garmin tech support. Here is our exchanges:
Thank you for contacting Garmin International,

The CF Que should acquire as quickly (if not quicker than the GPS III plus)
Make sure the cf que is plugged in all the way. Flip the antenna down to
turn off the cf que, then power the hand unit off. Wait 30 sec,take the unit
outside with a clear view of the sky, and power the handheld on. Then flip
up the antenna to activate GPS. If the unit still doesn't acquire, you may
have a bad que unit.

Please let me know if there is anything else I can assist you with.

Have a great day!
> Best Regards,
> Wade Slama
> Product Support Specialist
> Garmin International
Hafa Adai Wade,

My CF Que definitely is slower and less sensitive than my GPS III Plus.
What are the RF sensitivity specs on each of them?

I was just looking at an ad for a Pretec CF GPS unit similar to the cfQue
1620. The following is part of the specs listing:

Radio Frequency Signal Environment:
RF Input: 1575.42 MHz (L1 Band) at a level between -130 dBW and -164 dBW to
a reversed MMCX high-retention female connector
Burnout Protection: 0dBW signal within a bandwidth of 10MHz centered about
the L1 carrier frequency


The RF frequency bands are the same for each of them, as that is the signal
the satellites are broadcasting. If your CF Que is that slow and
unresponsive, it is probably a bad unit (most likely) or the Pocket PC you
are using it with isn't fully integrating with it. I would recommend either
exchanging the unit for a new one with the dealer you bought it from, or I
can set up a Return Material Authorization for you to get the unit repaired.
If you prefer the latter, I will be happy to set that up for you.

Hafa Adai Wade,

Please don't insult me! I am a retired Aviation Electronics Technician
(USN). I know that the frequency bands are the same. I was asking about
the RF sensitivity. Garmin hasn't put out those specs. At least anywhere
that I could find. I would really like to have some data to compare the
Garmin units with the Pretec.

Here is the RF data from the CF GPS made by Teletype:

CF v3.0 GPS Card #1653


Frequency: L1, 1575.42 MHz.
1.023 MHz chip rate
Channels: 12 Channel parallel tracking.
Antenna: External patch antenna via MCX connector
(extra cost may apply for antenna)
ROM: TeleType 1651 with automatic initialization
Sensitivity: -170dBW

You will notice the sensitivity figure -170dBW. That is a wee tiny RF
signal and indicates excellent sensitivity. The Pretec was between -130dBW
and -164dBW. The Teletype sells for $249.00 and Pretec goes for $160.00. I
would buy the Teletype. Not only for the sensitivity, but for a number of
other selling points in its' favor. Sensitivity is the major factor in the
selection of any type of RF receiver.


Hafa Adai Wade,

Have you been able to find out what the sensitivity specs are for the
cfQue1620 and the GPS III Plus yet?

Is the cfQue 1620 capable of using NMEA protocol? I've been trying to use
it with Memory-Map Navigator software to no avail. My GPS III Plus works
fine with the Navigator in both the Garmin and the NMEA modes. Is the cfQue
1620 supposed to be able to interface with third party software or is it
only to work with the Garmin software?



The Cf Que is not a nmea compatible device.

Standard GPS test signal level applied to the cfQue 1620 shall be -125dBm
+/- 0.5 dB.

If your cf Que is not acquiring, it most likely is getting RF interference
from your pocket PC's processor. Some pocket PC's will generate excessive RF
interference that will interfere with GPS reception, so it may not work well
on all handheld devices.

The GPS III signal strength is -55dBm

I hope this helps.

Have a great weekend.
Hafa Adai Wade,

I have been in touch with Tech Support at Memory-Map to try to find out how
to get the cfQue 1620 to work with their Navigator software. I received
this email from Ron today.


Dear Mr. Hildebrand,

I have looked over the data that you sent in the debug files. It appears
that Garmin has changed the protocol used for the position sentences for the
CF GPS. The CF units we have dealt with in the past all use an NMEA
sentence. This unit uses a Garmin sentence, but it is a different protocol
from that used in the other Garmin models. This appears to be an attempt by
Garmin to force people into using the Garmin maps. Our developers are
working to create a driver for the new protocol, but I have no idea on the
timeline for that feature. The device you used on the PC (the Garmin GPS
III Plus) uses the standard Garmin protocol I mentioned. If you can find a
way to change to mode on the CF card to an NMEA format, that would work, but
I do not know of a method to do that. I see no documentation in the manual
regarding changing interface mode. On the handheld Garmin units, you can
change the mode in the Interface section of the menu. If you have further
questions, please contact me at [email protected].


Ron Heintzelman

Ronald Heintzelman
Memory-Map, Inc.
(607) 532-4122
Hafa Adai,

My cfQue is acquiring satellites. It gets 2D lockons fairly quick, but 3D
is a bit sluggish at times. I believe your sense figure for the cfQue, but
not the figure for the GPS III Plus. -55dBm is ungodly poor. Evidently you
are not familiar with the dBm unit. It is measured on a logarithmic
-125dBm is humongously better than -55dBm for RF sensitivity. Talk
to one of your engineers and get them to give you a short course in decibel
measurement. I've been looking at data on a bunch of other CF GPS's. I
didn't know there were so many until now. The worst RF sense of the bunch
is the Pretec at -130 to -164. Even that is better than the Garmin. Of all
the units I researched, the Holux GM-270U has the best (-175) RF sense and
best feature set. It has a built-in WAAS that can be toggled on and off as
needed. I can buy one of these for $119.95 and use it with anyone else's
software except Garmins. It also comes with a software utility for test and
configuration. And then there is the capability of hooking on an external
antenna. I'm probably going to buy the Holux unit. I have used Garmin
products for many years and have always (until now) thought of Garmin as
being the top of the line GPS company. I'm very disappointed in you.


Well that's it in a nutshell. It would appear that Garmin has dumped a dud of a CF GPS module on us. They changed its' instruction set so that the only software you can use it with is theirs. They make it so that you have to buy their software AND hardware as a bundle. I was one of the first fools to dive in. Usually I wait until a few months after a new product comes out to buy it. That way I can read the reviews and message traffic to find out if it is really up to specs. This time I trusted in the Garmin name. Don't get me wrong. The cfQue 1620 is a very useable system. It just seems to me that it falls somewhat short of what I would normally expect of Garmin.
Back to top
View user's profile Send private message
Pocket GPS Staff
Pocket GPS Staff

Joined: 11/07/2002 14:36:40
Posts: 23848
Location: Hampshire, UK

PostPosted: Sat Jun 19, 2004 6:44 am    Post subject: Reply with quote

It is true that the cfQue does not output the standard NMEA data stream, they have instead opted for a proprietary protocol for whatever reason. They did the same with the iQue and for this reason I wouldn't consider either device.

Although Garmin's Mapsource products were unbeatable in times past, there are now many better options for mapping when coupled to a PC or PDA and so I cannot see the justification for choosing either of these products. There handheld range are still the best available though and I'm not denegrating Garmin as a company.
Darren Griffin - Editor
Back to top
View user's profile Send private message Send e-mail Visit poster's website

Posted: Today    Post subject: Pocket GPS Advertising

Back to top
Display posts from previous:   
Post new topic   Reply to topic    Pocket GPS World Forum Index -> Advanced GPS Lounge All times are GMT + 1 Hour
Page 1 of 1

Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

Make a Donation

CamerAlert Database

Click here for the PocketGPSWorld.com Speed Camera Database

Download Speed Camera Database
21.034 (22 Mar 23)


Click here to submit camera positions to the PocketGPSWorld.com Speed Camera Database

12mth Subscriber memberships awarded every week for verified new camera reports!

Submit Speed Camera Locations Now

CamerAlert Apps

iOS QR Code

Android QR Code

Terms & Privacy

GPS Shopping