New RTL-SDR + Upconverter Available

BA5SBA, the creator of the Chinese direct sampling kit (and fully assembled version) recently wrote in to let us know about a product that he is now building. His new product is a fully assembled RTL-SDR + Upconverter. The upconverter design uses a DBM balanced ring mixer design which he writes makes less noise and has greater dynamic range. He also writes that compared to direct sampling the upconverter model should have greater sensitivity as it allows use of the R820T LNA. His design uses a 40 MHz local oscillator, comes with increased RF input protection and comes in an aluminium case.

BA5SBA’s new upconverter can be found for sale on Ebay for around $80 USD.

We also posted previously about BA5SBA’s direct sampling kit here.

RTL-SDR + Upconverter in a box by BA5SBA
RTL-SDR + Upconverter in a box by BA5SBA
Example of reception
Example of reception
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The pdf manual for the upconverter version is here


guys, I’m so confused… I bought the Chinese pre-built BA5SBA 2015.04.29 RTL-SDR. I am trying to us it for picking up HF weatherfax and marine radio nets. I have the RTL-SDR hooked up to a Chameleon HF antenna but Im only hearing what sounds like a sinewave tone when I try to tune into the WEFAX Freqs… I have been on youtube and have seen many others make it work, but no one shows the steps… can anyone help me walk through how to do this? Do I need additional hardware? I have set my SRD# up for Direct Sampling in the Q branch, I’ve got the antenna attached to the HF side, I’m racking my brain trying to understand what I’m missing here. any help would be appreciated!


this is what I bought.



Did I miss this somewhere? What additional frequency range does this upconverter allow the rtl-sdr to receive?


Without the upconverter, this particular SDR goes down to 25Mhz. With the upconverter, it goes down to 100kHz.


Another disappointment.

Given the very poor dynamic range of these ubiquitous $10 – $15 RTL dongles, with only 8 bit ADC or 48 dB of dynamic range, just more poor performance (e.g. without the needed input filtering).

When your input is an open barn door, your output will be too (+ all kinds of mixing products).



I really enjoy making filters, and this program makes it a snap.

David / SM0ULC

Zeke, expensive dongles? fc+ is about 200 euro. 5 Dongle on ebay is 5 euro.


I am glad for choices. Few humans on this planet have identical knowledge, preference, capital and opportunity. I prefer to have more than 192KHz of real time bandwidth. I also enjoyed giving 6 RTL dongles away to interested engineers and keeping one for myself, for the same price as a single FunCube. Upconverters are fun to have around, as are downconverters. Glad to have choices.

Simon Franklin

My Dear SDR-er’s,

Why are you struggling with all this external hardware when you already have the: FUNCUBE dongle PRO+…

With only moderate noise protection required I have been enjoying SDR HF for years now, as good as 99% of the HF radios out there in RX.

Or are you so cheap that you are waiting for a $10 R820T for HF…….forget it and move on.



Folks with your “must have t3h b3sT!!!” attitude toward radio related disciplines are one of the big problems with the hobby. Some people can’t afford an FCD, because they have more important things to spend money on. Don’t get me wrong, I own one, and have a Softrock RXTX on the way, but I struggled to afford both, and for people who are just dipping their toes in the water, $100 is a lot of money to put down on something it’s entirely possible they will only use once.

With a DBM and extra shielding this kit is a much better performer than the previous version, my only qualm is that should be a R820T2 dongle in there nowadays.


Oh dear , you read my mind : P


I have this dongle but I cannot make it work in HF with linux. It works well in vhf/uhf. But when I switch to HF using the physical switch on device and I run an “rtl_test”, I get “No supported devices found”. But when I run it with vhf/uhf mode, it works. What is the problem here? Is the problem related to physical upconverter circuit or is it like a driver problem?