New AUZEUNER 25-1.7ghz 0.5ppm + BiAS + HF


#1

Hi all
Purchased 1 of these and bit lost as I thought it was latest from rtl-sdr.com
works out of the box fine but that’s about it
tried the RTL -SDR bias software not working
any help on the workings would be nice if some has already sussed it


#2

So … Does it work?


#3

Yes it did work but with no amp or filter (to my knowlwdge) it didnt perform as good as i had hoped on 1090mhz
i was a little confussed by the print on the dongle
was hoping a bias (tee) might have been included but nope

  • bias + Hf ?? as it’s 25mhz - 1.7 ghz

#4

If you have the time and inclination, would you mind taking the cover off and taking a pic? (the bias-t circuit should be obvious if it’s there)


#5

Sorry for delay
heres pics you wanted
totally different layout


#6

Thanks for taking the time. It’s certainly different to a generic ‘RTL’.

Generic dongles often have the PCB pads to take either a linear or switch mode Voltage Regulator (linear produces less noise, but more heat).

This dongle appears to have three regulators (two switch mode and one linear(U32)). I can’t identify the SM devices (package code AABAA) and I can’t read any marking on the linear reg, but a 1117-3.3 is a likely candidate.
I’ve marked the input clamping diodes D6 (package A7) that protect the input to the 820 (I haven’t seen a dongle without diodes in this location).

L9 provides a DC path to ground from the antenna input and the bias circuit is completely absent.

I’ve marked the crystal as TCXO, but I haven’t matched the part number to confirm it is in fact a TC device.

“HF” is generally understood to mean 3MHz to 30MHz (LF is 0.3~3MHz, VHF is 30~300MHz)

In my opinion, this is a significant step up from a generic dongle, but it’s certainly not a match for the RTL-SDR Blog V3.
However, I also think the name / claims are misleading at best.
Perhaps this is a case of ‘alternative facts’.
I’d suggest anyone looking for a ‘better than generic’ dongle, to keep looking.


#7

If you must go with a generic RTL-SDR, there is no reason not to go with the RTL-SDR Blog, unless the ‘100% premium’ ($9) over the no-name generic breaks the bank.

That said, for the majority of hobbyists, the FA dongle is the way to go. Learn all you can with this basic, and in most cases best setup, before spending time and money experimenting with other hardware.