I bought my HDG2002B in December 2015 and have applied some modifications to make it better suit my needs (and to satisfy my curiosity...). I'm using it quite frequently since Hantek found better solutions for some details than Rigol on my other AWG (DG4102). My HDG2002B is currently configured as follows:
Hardware: PCB 1004.1
Modifications:
- LAN interface
- High frequency divider for frequency counter function and corresponding input socket
- Suppressor diode to limit floating (analog) ground voltage to frame ground to 40V
- Device ID changed to operate as a HDG2102B
- Automatic calibration performed to have the amplitude accurate over the extended frequency range
Current firmware configuration:
S/W: 1.00.3.03.11 (2017/11/15)
Linux 3.2.35
FPGA: 90
KBD: 3
This isn't the most recent firmware but I found this version to be working troublefree with my hardware and to support all functions well. I don't recall to have the unit crash over the last year. Actually, currently I like the Hantek more than the Rigol, simply since changing parameters on-the-fly produces a less glitchy output.
At the current price of round about 205 Euros shipped, I think this AWG is leagues ahead of all the "Feeltech's" and whatever is available of this pedigree. Of course, it's approximately twice the price of those but still at least half of anything else (new that is) that can be considered half-way decent.
What modifications are worth to apply: Since I've got sufficiently decent frequency counting equipment anyway, I wouldn't add the UHF divider and input socket again. Except for curiosity's sake, I never turned that option on. Moreover, other than on my Rigol AWG, the frequency counter function on the Hantek can be considerd at best half-baked firmware-wise. So, just forget about that. The LAN interface actually is a nice thing to have -- unfortunately, it requires considerable effort to add. Only recommended for those with experience soldering fine-pitch SMT. The suppressor diode modification is something I'ld really recommend to add. I like the fact that the ground of the Hantek AWG is floating so it wouldn't cause any ground loops if operated stand-alone and connected to other earth-referenced equipment. Of course, if the USB interface is used and connected to a ground-referenced PC, this advantage is lost. But since the Hantek utilizes a switch mode power supply with RFI suppressor caps across the isolation barrier, some capacitively coupled mains voltage / current will be found on the analog ground (like it's the case with a lot of consumer electronics gear). There had been some discussion going on here if the creepage distances of the Hantek PSU are adequate for a safe operation -- I tested the AWG with a megger at 2.5kV and didn't find any problem. The (quite substantial) suppressor diode that I added between the analog ground and earth (frame) will limit the coupled voltage to 42V and at the same time still permit some degree of floating ground operation - in my opinion the best trade-off between the unmodified, original configuration and a completely new, linear power supply (what I intended to add but finally dropped the thought after the machine performed well enough like this).
So would I recommend the HDG2002B as a piece of lab equipment for a newbie? No, definitely not! But for an advanced hobby user it can be quite a valuable, inexpensive instrument. For a professional, even though it matches the specs after calibration, it's just not adequate, of coure also always depending on the application in particular.
There's one more issue to observe: Reportedly, some earlier hardware versions aren't compatible with the recent firmware versions anymore. Moreover, I don't know what the current hardware revision is. At least Hantek appears to continue to support the HDG2000B series software-wise wtih an update every few months which is more than what many other manufacturers may claim for them. And since the instrument is running Linux, it's not a complete "black box" but experienced users may help themselves in case of problems.
I hope this information may be some food for thought to those who are considering to get themselves one of these AWGs.
Cheers,
Thomas