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Reviews For: Leo Bodnar Electronics GPSDO Precision Frequency Reference

Category: Tools & Test Equipment for the amateur radio work bench

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Review Summary For : Leo Bodnar Electronics GPSDO Precision Frequency Reference
Reviews: 15MSRP: 250
GPSDO Disciplined Oscillator Precision Frequency
Reference, 450 Hz to 800 MHz GPS Locked, Low-Jitter Clock
by Leo Bodnar Electronics distributed by Airspy.US
Product is in production
More Info:
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
W4BSS Rating: 2023-03-30
Stable and extremely accurate! Time Owned: more than 12 months.
I'm using Leo's single port GPSDO with my Kenwood TS-890 and I must say it is extremely accurate and stable. Definitely worth the money for 100% accuracy for your HF rig.
W9AC Rating: 2019-06-15
Compact, stable, and accurate Time Owned: 3 to 6 months.
I'm using the dual port model. Output 1 is set to 10 MHz, output 2 set to 48 kHz for synchronizing the sampling rate to digital audio devices with wordclock capability.

Extremely sensitive GPS receiver. The unit locks with the antenna sitting on the shack floor but it comes with enough RG-174 coax so that it can rest on a windowsill. Locks to GPS in seconds.

Can be powered by USB alone. Very low current drain. The software is simple and easy to use.

The holdover accuracy (during unlock) is not quite as good as other GPSDO devices but with such a sensitive antenna, I have yet to see holdover occur unless I force it for testing.

Phase noise performance is very good but not in the same class as the Trimble Thunderbolt and Datum LPRO 101 when powered from low-noise power supplies. Still, a solid 5 and highly recommended.
VK4SX Rating: 2019-06-14
2 years + use Time Owned: more than 12 months.
Excellent product, hassle free operation, very stable,
K3 (S) & IC-7610 Connected, perfect,
very versatile.
Dennis vk4sx
PA3MET Rating: 2019-06-14
works fantastic and no drift issues Time Owned: 0 to 3 months.

I am feeding my 9700 and 7851 with the ref signal and they both work flawless.

(With the v1.10 f/w and up of the 9700 the drift "issue" is gone too)

The only downside is that Fedex again, just as always did a bad job. But that's not really the unit's fault.
VA7ION Rating: 2018-06-28
Must have Time Owned: 0 to 3 months.
I own the Mini GPSDO. This little device is a must have for any self respecting ham. 4 power levels and 1 ppb stability with usually few seconds to lock onto the new programmed frequency make your instrumentation calibration a breeze. The GPS antenna is extremely sensitive, works just as good inside the house as outside. Strongly recommend purchasing one.
G4AON Rating: 2017-07-19
Nice product, better instructions needed Time Owned: 0 to 3 months.
At £150 delivered to a UK address, the Leo Bodnar unit is too good to not have in your shack.

As currently delivered, the unit arrives "bare". You get a USB lead, GPS patch antenna and the unit itself.

While the supply Voltage is shown as 5 to 14V, when running from a 13V shack supply it runs hot. A 5V supply keeps it cooler. It can also be powered from USB.

The Windows programming software is a 140 KB download from their site and is fairly easy to use. On my Windows 10 PC, there were no drivers to install or any other issues, the software "just ran" and found the unit without any messing around. It is easy to use the software to set more or less any single frequency in it's range of 450 Hz to 800 MHz, enter the frequency in Hz into Output 1, press "Find" and the unit changes to that frequency, settling down after a few seconds.

The slightly trickier problem was how to program a 10 MHz and 1 MHz simultaneous output, as the programming software (ver 9.11) didn't give an output option of 1 MHz for output 2 when set for 10 MHz on output 1. A little investigation suggested that manually changing the parameters might produce the required outputs. For those with a similar unit, the way to set O/P 1 to 10 MHz and O/P 2 to 1 MHz is as follows:

Enter 10 MHz in output 1 and press "Find"
Change the entry in NC2_LS from the 10 MHz setting (48 in my unit) to ten times that value (480) and press "Update". The outputs will now be 10 MHz and 1 MHz. Note at this point the unit will retain the settings, but the software will not show O/P 2 correctly, close the software and re-run it if you want to read the frequencies from the unit.

The only downside is the lack of instructions...
K1FPV Rating: 2016-11-10
Great GPSDO For The Price! Time Owned: 0 to 3 months.
I already own a Spectracom "GPS Ageless Master Oscillator" as well as an HP 58503A where they both are functioning fine. I purchased this one though in that you have the opportunity to program it to produce a different output frequency other than the normal 10 MHz reference most GPSDOs produce.

Comparing it to the HP and the Spectracom, it is dead on frequency as the others when set to 10 MHz. I then programmed it produce a frequency of 15.60000 which is the frequency used by the Kenwood TS590. I monitored it's stability on that frequency with my B&K 1823A Counter (capable to read down to .1 Hz) referenced to the Spectracom. It remained dead on 15,600,000.0 which is as close as the B&K would read.

The unit I purchased is the low noise version which is a few dollars more, but I am 1000% happy with it! I highly recommend it as a frequency reference.
SHORTWIRE Rating: 2016-10-13
Great Flexibility at the (small) price of some Stability Time Owned: 3 to 6 months.
A Real Bargain!

This device appears to have a bit less stability than most surplus competitors, in return for a lot more flexibility.

You can take it portable for microwave experiments, without the need to set a position. just connect and go..!

Low power consumption (250mA at 5V)

Small size and weight

Appears to run in navigation mode, so no survey or position setup needed. You just turn it on, and one or two minutes later it is ready for use.

Uses a modern u-blox chipset, so sensitivity is as good as it gets today.

Can be set to any frequency between a few KHz and over 800MHz, which will be locked to GPS with the below mentioned stability.


Its frequency stability appears a bit worse than most old surplus competitors, probably due to its use of a TCXO, rather than the more common OCXO.


When measured on my HP 53132A against my HP 58503A, i see frequent jumps of up to about 0.3ppb, so it might not be considered TimeNuts grade in its performance. Or I might have done something wrong(?)

Best points is the size, weight, power consumption and price.

It is a very flexible device, excellent for most HAM use, perhaps short of the most critical tasks like JT or WSPR on 10GHz+.

If your needs are less than these, it is very highly recommended!
VE3YF Rating: 2016-10-13
Very Handy and Reliable Time Owned: more than 12 months.
I purchased one of these units to correct a finger problem at this end. It might have seen like overkill but it definitely did the job, so well in fact I leave the GPSDO on 24/7 and hooked up to both of my SO2R Station radio's. Not only did this unit fix my finger problem, it also serves to keep my radio's both on frequency. I power the GPSDO right off the desktop computer's USB Port. Setup of the unit is very simple, just follow the simple computer program and it takes care of everything. I had thought of an alternate unit from China, but changed my mind and I am glad that I did. This unit has given my piece of mind and zero issues, what more could you ask for.
If you have a finger problem like I did, with this unit you can't go wrong when you are looking for a GPSDO, and Leo is only an email away for support or Force-12, something I have not needed to date.

Earlier 5-star review posted by VE3YF on 2016-10-12

I ended up purchasing one of these GPSDO's as one of my radio's was off frequency. Why it was off frequency was a finger problem at this end. To bring the radio back on freq I got the GPSDO. I leave the unit plugged into the computer USB port 24/7 and it has never failed. I have both of my rigs hooked up to the GPSDO and I purchased a somewhat cheap GPS antenna and the GPSDO finds the satellites rather quickly. Setup is very easy, just download the setup program and follow a few simple steps. I could not be happier with my purchase.
KD8DZ Rating: 2016-10-12
High accuracy cost effective GPSDO Time Owned: 3 to 6 months.
I have used the LeoBodnar GPSDO a good bit so far and it functions as advertised.  I had several questions which I posed to Leo, and he quickly addressed them.  It is always a good sign when the people who make an instruments provide timely support.  I have used the DO to calibrate my K3 by using the "spotting" function on the K3 and zero-beating the 10MHz signal.  Calibration using this method is good to +/- about one Hz.  I also use it to check the calibration on my HP8657A signal generator and a Tektronics frequency meter.  In the future, I plan to install an improved TXCO and the 10MHz K3EXREF  Ext. Frequency Reference Input card in the K3 and lock to the GPSDO.  I would also like to use it as the basis in some of the future precision frequency tests sponsored by ARRL as it has sub Hertz capability. I might also add that I agree with the previous reviews of this device.