RTL-SDR Blog Units Back in Stock + Polling on Future Upgrades
After a few delays our RTL-SDR blog TCXO/SMA/Metal Case units are back in stock at the Chinese warehouses. The restocking of Amazon USA will follow shortly, and they should be ready for purchase on Amazon by the end of next week. See our store for information on purchasing.
As some readers may know, we’ve been working on finding ways to improve upon and add features to the RTL-SDR’s we sell, whilst trying to maintain the attractive low cost. In previous batches we added upgrades such as a TCXO, bias tee, SMA connector and a shielded metal case with passive cooling. For future modifications we’d like to poll the community on what is most desired.
In the poll below please choose your top 3 desired improvements. If you desire something else please comment on this post. Thanks!
[poll id=”4″]
I voted for higher ghz coverage so we can get into true WiFi. And dect areas plus who knows what else is around… Maybe even upto 6ghz to compete very nicely over them hack rf that cost £300 or so which is ridiculous. Upto 3ghz eve would do me and would purchase a v4 so I hope this is a feature you are deeply considering. I did purchase also a nooelec which promised the earth and was deaf as a post up 2ghz+!!
Hello, when you can sell these new units ?, I need to buy a new one, and if these are soon is better to wait, thanks.
I have already purchased version 3, thank you for your work, and thank you for the price so content.
Have you thought about creating two different models? Keep the current model with updates that won’t affect the cost much and a higher quality model with added features but still make it relatively inexpensive, maybe around $30-50 USD?
I would like to see a optional power INPUT intheRTLdongle as I have a suspicion but cannot prove it, that my RTL dongles may have overloaded and caused some of my Android TV box’s to fail (fixed under warranty). Also my Orange Pi had a USB burn out from running a RTL dongle.
These under-powered Arm devices may not have enough power to run the RTL dongle all the time. If there was an option to self power the RTL dongle it might get around this issue especially when used in remote locations. ie up next to an antenna etc.
The number of votes received from “Built in HF capability” make me think that about 50% of the readers are looking for a cheap gadget all in one; a sort of competitor of the BA5SBA. That means moving in the wrong direction IMHO
Why do you think built in HF is going in the wrong direction?
Because it’s plenty of upconverters that perform better than a direct sampling mod. We’re going below the minimum quality acceptable even for an entry level.
It doesn’t make sense buying an improved dongle with a worse HF receiver IMHO.
I still see space for another upconverter (a separated pcb) if competitive in price and shipped free of charge from China like you do for the dongles.
Thanks for your answer. I’m thinking that we could add rudimentary direct sampling support to at least give a taste of HF (e.g. even a basic direct sampling connection can receive the AM broadcast band with a short wire antenna). This shouldn’t increase the retail cost from what it is now. Adding extras like a matching balun or HF amp to make direct sampling almost as good as an upconverter may increase the retail cost a little, but we’ll experiment to see if it is worth it.
Either way an upconverter will still be an option for better HF performance, even if there is some sort of HF capability built in.
Lower internal noise i what we have always looked for but i doubt that a good job can be done without designin a completly new pcb; it cannot be done just adding components and small modifications so it can become expensive.
There are many other nice things that can be added but only one is really needed since the beginning and will show immediatly the difference compared to a standard dongle, that’s the FM band stop filter; so that’s where you should start from.
I agree with the FM bandstop being needed. There are a few decent ones for sale now, but we’ll see if we can make a better and/or cheaper one.
I wouldn’t mind a female USB micro-B option to make it easier to place further away from a computer.
I think a low cost external bias tee powered LNA would be a great idea. Have it connected directly to the antenna and an F connector out so RG6 can be used. Offer that with a dongle with an F connector and that would simplify a whole lot of peoples installs.
Of course, what connector do you put on the antenna side of the LNA? N? PL259?
Brian, PL259s are not suitable for a device that can receive into the GHz range.
I think it needs a external LED so you know it is on.
I have a cheap Chinese RTL dongle and it has a blue led. I always remember to turn it off. But my new aluminum RTL dongle accidentally gets left on. I can only tell if its on by the touching it and feeling the heat.
It’s funny, many people requested that we remove the LED from the last batches. We decided to remove it because its just a non-essential extra component with long leads that can pick up interference. Plus adding another hole into the metal case would allow some RF to get in.
I would love to see a 10Mhz reference and 1PPS for precision time and frequency.
Maybe consider bundling a short (6 inches or so) male-to-female USB or coax pigtail? I worry about torque on the USB connector where it plugs into my PC when I have coax attached to the module. (My outside antennas come in on RG-8X or RG-6 coax, both of which are pretty stiff.) Having a flexible connection somewhere in the chain from computer to module to coax means a slight movement of the coax won’t break the USB connector.
I have adaptors to go from my various antenna cables to a female SMA connector, but all my SMA jumpers are male-to-male and won’t work with them.
Voted for “less noise” and “HF capability”. I suppose the latter means < 14Mhz support with some kind of direct sampling mode, buillt-in this time? Thanks anyway, I've bought one from the previous batches, and will most definitely buy another one from the enhanced batch !
I voted for lower noise, and I assume this means possibly the following:
1. Deal with the noise from the USB shield, ideally with RF chokes
2. Bypass capacitor across V+ / ground
3. maybe do something to suppress IF harmonics
I’d also note that nothing-and-I-mean-nothing improves that system NF better than an LNA, preferably as close to the antenna as possible.
I fully agree I am surprised that “Switched Internal front end LNA” currently (it will probably change) has more votes than “Low cost external bias tee powered LNA”
noise+signal -> attenuation from connectors, attenuation from cables, additional noise from everything along the entire signal path -> LNA @ receiver
vs
noise+signal -> LNA @ Antenna, signals levels would be higher along the path and be degraded far far less -> receiver
With a small amount of gain at the antenna the signal levels would be higher than any detrimental effects it would encounter along the signal path.
The popularity of that option is surprising to me too. Even if it’s popular we probably won’t go with that option as many people may not understand the effect of proper LNA placement.
Thanks for the feedback. Yep if we were to add HF it would most likely be some sort of built in direct sampling connection.