The iG4 (released
October 2019) is the fourth
generation of the popular iG3s, X900S-OPUS and X90D-OPUS receivers which
were first released in June 2013 by iGage.
The iG4 tracks more
satellites (GPS + GLONASS + Galileo + BeiDou) with a huge channel count.
Complete differences are listed [ here ].
price seems too low, is it too good to be true? This is
the #1 comment from callers inquiring about static receivers from
iGage. Please be
assured that these receivers are extremely well built.
The accessories are first class and the hard-shell carry case and
foam insert will protect your receiver for years of hard service. The GPS
engine is top notch, the ground plane antenna is large, well anchored, the phase center tolerances are tight and
extremely well matched between devices and the Lithium-Ion batteries
are top of the line. With 4-gigabytes of flash
memory, you can keep months worth of observations on the device.
These receivers are built specifically
for iGage by one of the largest (and we think the best) GPS
manufacturers in the world. We designed it to exactly fill the
requirements for static processing with no extras.
We (iGage) write and maintain the
software tools and provides fantastic service and support. The iG4, like its predecessors is the 'Real-Deal.'
1. How long will the
iG4 run on a
battery? A new battery at 70 deg F. will typically last 6
hours and 30 minutes. We supply 3,400 mAH batteries. A wide range of
aftermarket batteries are available. Typically 3rd-party batteries are
advertised as 2,200 mAH
batteries and will power the iG4 for around 4 hours.
An external battery clip cable is included in each kit
for attaching the receiver to an external 12-volt battery. We also
have optional heavy-duty cables available.
For applications with line power available, the power supply for
the battery charger will also power the head. (And the external
power clips will power the battery charger for charging cells at a
remote location.) An internal battery is not required (however we
recommend that you still use one) if external power is provided.
2. How long does it take the supplied charger to
recharge a battery? From empty to full charge it typically takes
hours to charge a battery. You can charge four
batteries at once with the supplied charger.
3. How much memory do
these receivers have?
4-gigabytes. When the download tool copies
a file from the receiver, it leaves the original on the receiver
with a '_' pre-pended on the filename.
satellite counts (22-300 the iG4 generates approximately 1.75
megabytes per hour.
The internal memory
is large enough to store 90 days (24-hours / day) of 5-second interval data.
4. Has the antennas been calibrated by
the NGS? Yes. The antenna is also listed in the OPUS
dropdown box. Calibration files may be found [
5. Can the
iG4 be used as a RTK receiver? The iG4 does have
Bluetooth and it is possible to configure it to be a RTK Base,
sending corrections out the serial port.
6. Can this
receiver be used as a source of network real-time corrections?
It is not a great choice: it does not have an Ethernet port, it
would be relatively difficult to configure with an external Serial
to Ethernet adapter. Checkout our [ network
purposed ] receivers for an inexpensive, perfect solution for this
7. Why do you
have to paste (Control-V) then press enter to fill in the ZIP
filename when submitting to OPUS? The Internet Explorer
has a reasonable security precaution that will not allow a program
to automatically upload a file from your computer to the internet.
If the iGx-Download tool could automate this step, then a malicious
program could steal your address book, or any file, from your
8. Why does
the download program decimate and ZIP observation data?
OPUS initially decimates submitted data to 30-second intervals, so
there is no reason to submit higher rate data. We ZIP the submitted
files to shorten the upload time.
For alternative services and RINEX
files exported with the 'Export' button, the tool exports full rate data
9. Does the
iGx Download tool support OPUS-Projects? Yes. See page 34
in the User Manual.
Would the iG4 GNSS receiver be a good choice for a large highway control
The iG4 receiver is a fraction of
the price of alternative devices. Given the same hardware budget,
you could purchase three to 8 times more iG4 receivers than you
could using repurposed RTK heads. More receivers allows densifying a
control network with fewer sessions.
11. The batteries look familiar, can I
use another source? There are also several third party
replacements available on Amazon and eBay that may work, search for
'Trimble 5800 Battery'.
You will find that our batteries are
the highest quality Lithium-Ion batteries available and the 3,400
mAH capacity is higher than most alternatives.
cautioned to ONLY only
charge CHC batteries in the CHC charger and to not charge alternate
batteries in the CHC charger. Intermixing charging
technologies (for example charging CHC batteries in Leica chargers)
is asking for a meltdown and possible fire.
In other words "All
of the 7 volt Lithium-Ion batteries that fit in the hole, probably work well"
but we are not responsible for issues and mishaps that occur with
batteries that we don't sell.
you want to search Amazon for compatible batteries, try this link [
Compatible Batteries on Amazon ]
Yes. L5? Yes.
432-channels, 4-constellations, 5-hz rate, tracking:
GPS: L1, L2, L2C
GLONASS: L1, L2
BeiDou: B1, B2, B3
Galileo E1, E5a, E5b
3.02 RINEX output
files have these observables:
G 12 C1C C2P C5I L1C L2P L5I S1C S2P S5I D1C D2P D5I SYS / #
/ OBS TYPES
R 8 C1C C2P L1C L2P S1C S2P D1C D2P SYS / # / OBS TYPES
E 12 C1X C5X C7X L1X L5X L7X S1X S5X S7X D1X D5X D7X SYS / # /
Sample output files
are available [
13. What is the
difference between a iG4 and other receivers?
In a nutshell: Price, download
simplicity and performance.
It depends on
the specific GNSS model that you are comparing to. Here are the possibilities: Bluetooth or No Bluetooth; UHF
Radio or no UHF Radio; Cell Data Modem (three models) or no Cell
Data Modem; 32 Megabyte flash or 4 GB flash; USB Flash drive
interface or RS232 Serial Interface; GPS or GNSS; "+" or no
"+'. There is a huge variety of GNSS engines available in the
Who does warranty and non-warranty service on
these receivers? iGage Mapping Corporation in Salt Lake
City provides service on the iG4 receivers. The receivers are
warranted for 2-years, accessories for 1-year and batteries for
15. Is the
iG4 a good solution for aerial survey applications?
Yes. Unless your application requires recording faster than 5 Hz. The internal GNSS boards are enabled for 20 Hz
recording, however there may be issues recording at this rate with
low elevation masks due to the higher data rate.
16. What is
the maximum recording rate for static observations? The
iG4 will record 5-Hz (5 observations per second, 0.200 second
spacing.) 16B. Are higher data rates
(faster than 5Hz) possible? Please call us.
17. What about
a Tripod? Fixed height tripods are best. We include a
Stedi-Rest with every receiver: [ Click Here
What kind of data tests are performed
by the iGx-download tool?
- Observation files shorter than
the programmed length (7,000 bytes by default) are outright
- Observation files without
navigation messages are flagged and transferred to the hidden
- Observation and navigation
files are checked for minimum RINEX structure requirements.
- MP1 and MP2 are monitored for
gross problems, although only severe issues are flagged.
- Warnings are generated if the
proper antenna model, HI or email can not be automatically
filled on the OPUS submission
form. (As opposed to just continuing with a default antenna
- Email addresses are checked to
insure reasonable form.
- Occupations are automatically
classified as suitable for OPUS-RS or OPUS-Static.
- Occupations longer than
48-hours are rejected.
- Occupations shorter than
15-minutes are rejected.
- Occupations that ended after
the top of the current hour are flagged as probably having no
overlapping CORS data (yet.)
- For the first 15-minutes of
each hour, occupations that ended in the previous hour are
flagged as probably having no overlapping CORS data (yet.)
In addition you can trim the
beginning or end of any occupation.
We have 'built-in' functions so you
can share your screen with our support staff and you can submit
entire 'problem' jobs with all meta-data to us for us to look at.
When I enter "2" meters for an
HI, the download tool displays "2.000,0"; what's up with that?
The download tool is inserting a comma to make it easier for you
to discern 1/10th millimeters:
Which is easier to
read? 4743107.431 or 4,743,107.431
2.1315 or 2.131,5
Does the iG4 track L5? Yes, see question 12 above.
you download files from the receiver while it is recording data?
No. When you connect the USB plug, the receiver stops recording data
and emulates a thumb drive.
sessions are enabled, do the sessions start at the top of the hour
or 1-hour after the file is opened?
Sessioning happens after the
programmed time has elapsed. A new occupation file is NOT
automatically opened. If you want to record data for an extended
time, call us for help.
How long will the iG4 run on an external
battery? The iG4 draws 0.3 Amps from an external 12
volt source. As the terminal voltage of the external
source drops, the current draw will increase. The iG4 will revert
to the internal battery when the external voltage falls below ~8
24. If the
receiver is set to 30-second epochs, how long will it store data
before the internal memory fills? It depends on the
recording rate, elevation mask and number of satellites that are
tracked. For 5 hz, 0 deg mask and 22 to 30 SVs 1,750,000 bytes per
hour are typically generated.
4 GB / (1.75 meg / hour * ( 5 second /
30 seconds ) ) = 13,700 hours = 570 days
What happens if the battery runs out during an
occupation? If the battery runs out, or the battery is
removed while the receiver is storing data, the file is left intact
in memory. No epochs are lost. This has been extensively tested.
What happens if external power is attached?
The iG4 will run off of external power until external power is
removed and then switch to the internal battery. The internal
battery is not charged by the external power source. We strongly
recommend that you always have a internal battery in the head
because the antenna is calibrated with a battery in the receiver.
What kind of RINEX file is exported?
2.11 by default. You
can manually generate other RINEX versions. Samples are available [
What about 'Elevation Mask'? The
iG4, by default, is set to record satellites above 0 (zero)
degrees. OPUS ignores observations below 10 degrees (this used to be
15 degrees however it was changed to 10 degrees.) We want the engine to begin tracking SV's as soon
as they are visible so that as they rise to 10 degrees they are
fully tracked and locked.
It is possible to change the
minimum value using the 'Receiver Settings' area of the 'GPS
Settings' tab in the download tool via the serial port.
Did I read that the iG4 receivers
write a RINEX file as the onboard data storage? The
iG4 stores occupation data in a proprietary file format with
the extension '.HCN' in the flash memory inside the receiver.
tool automatically convert the .HCN file to standard RINEX (see FAQ
#27) when the file is downloaded from the receiver.
Here are some
good reasons to like the '.HCN' file format:
The HCN file is
compressed. A 9,357,164 byte '.HCN' file is 28,944,578 bytes
when converted to RINEX (32% of original size).
format is engine neutral, we can change out the internal GPS
engine to an alternate brand or model and still write out '.HCN'
files and use the same conversion tool to generate standard
I would like to purchase a campaign set of
Great! However we no longer offer prebuilt campaign kits. We think
that you are better off having 6 separate cases than one huge coffin
sized case. Plus, they cost less too.
What about REALLY long occupations? Will
the iG4 record data for multiple days? Yes, see question
24, call us for
My Yellow and Green LED's flash simultaneously
and the receiver won't store data files. Whoops, you
allowed the battery to run down while the device was attached to a
computer. Instructions for checking the flash drive and reformatting
it are in the User Manual page 51. (Or just call us and we can help you out
What are the
differences between the X90D-OPUS (original static receiver) and the
iG4? Here is a list with explanations:
iG4 tracks 384 channels
instead of 24, more is better of course
iG4 is smaller and lighter weight
iG4 has Bluetooth and works as an RTK Base
iG4 tracks GLONASS, Galileo and BeiDou, this helps the receiver continue
to track under heavy canopy
iG4 comes in a smaller hard case, easier to pack, costs a
little less to ship
iG4 charger holds 4 batteries instead of 2
iG4 battery is qty 1 3,400 mAh instead qty 2 2,200 mAh (we only
ship one battery standard now)
iG4 runs longer on the new battery than the X90 ran, however
the iG4 does use more power
New 3,400 mAh batteries are $120 instead of $90 for 2,200 mAh
iG4 battery is shipped discharged and inside the head (because
of new shipping regulations)
iG4 MSRP costs $2,400 instead of X90-OPUS $2,450 MSRP (however
the street price is probably more)
iG4 includes Ground UPS shipping instead of 3-Day Select
(required because of new shipping regulations)
The new optional 2-meter heavy duty cable is only $100 instead
are there blue and red 'iG4' stickers on the side of the receiver?
When you take a side view picture of the receiver over a mark there
will be a distinguishing feature
that identifies the correct antenna model. The stickers make it clear that this is a
and not a X900U-OPUS, X900+ or one of the other similar devices.
34. If I
want to manually process the observation files, what tool should I
You can use any tool that has the 'iG4' antenna model and accepts
standard RINEX files. Some tools won't have the iG4 antenna model,
but might have the iG3s model which is nearly identical.
CGO2 from CHCNave is a great,
inexpensive tool that is purpose made for the iG4. You should use
our download tool to download and convert the native files to