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Author Topic: RTL-SDR maintenance help needed  (Read 205 times)

Offline Telegrapher

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RTL-SDR maintenance help needed
« on: April 28, 2019, 0902 UTC »
Hey there, I have a RTL SDR dongle that needs some maintenance. I measured the two coaxial plugs on the dongle which both seem to have short circuit in them. I tried to disassemble the dongle but I canít even slide the side panels off after removing the screws. So Iím wondering if itís worth the time to try and get it disassembled and get new coaxial connectors. Or just buying a better one? Itís not a high end dongle so I just need some advice on what to do with it. I bought it for quite a bit (Ä58,-)

Any tips and info is appreciated.

Kind regards,
Telegrapher

Offline Josh

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Re: RTL-SDR maintenance help needed
« Reply #1 on: April 28, 2019, 1908 UTC »
Stash it away for parts and get a RTL SDR V3.
Conveniently located near Vincennes Indiana.

Offline Stretchyman

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Re: RTL-SDR maintenance help needed
« Reply #2 on: April 29, 2019, 0613 UTC »
Just because you measured a short (at DC) doesn't mean there's a short (at RF)

Do you get any signal thru'?

Str.
'It's better to give than receive' so why RX when you can TX!

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Offline Telegrapher

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Re: RTL-SDR maintenance help needed
« Reply #3 on: May 07, 2019, 1152 UTC »
@ str - I only get signal through it when I only connect the center conductor without connecting the shielding. If I connect the shielding by screwing the coaxial cable to the plug of my SDR, all signals are completely gone and the waterfall is empty. So I assume that the SDR is just in a bad condition.

@ Josh - I am thinking about buying a better SDR anyway, so I appreciate the tip. As Iíve seen many different kinds of SDRís on the web, I am at the moment just wondering which one is the best one to get. I first was thinking about buying the Kiwi-SDR, but the SDRPlay also looks promising to me. So I need to make sure that I donít waste my money on buying a SDR that doesnít seem to fit my needs. I just want to listen to shortwave mostly. Besides that a little on the fm side (77 - 108 MHz).

The SDRís I am looking at are the following:

Kiwi-SDR
SDRPlay
HackRF
Win radio pci card
RTL-SDR v2 or v3

Just wondering which one is the most fair one to get. I just need good performance just like my analog radio does.

Kind regards,
Telegrapher

Offline ChrisSmolinski

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Re: RTL-SDR maintenance help needed
« Reply #4 on: May 07, 2019, 1424 UTC »
I'd strongly advise against buying another RTL dongle for HF. Good money after bad. I have two of them and they are OK for VHF/UHF work, I use one to listen to our county's trunked radio system on 900 MHz. Great value for $15. But for HF use? Forget about it. After you buy the converter, then spend money on a low pass filter to get rid of images, you still have a poor performing SDR, and are more than half way to a much much better SDR.

I have a few SDRs:

The KiwiSDR is probably the "easiest" SDR for most to get running. It's a self contained box with a CPU that acts as a web server. So no USB drivers to install, etc. You just plug it in, configure it, and use it on your computer via a web browser. You can use it from multiple computers at the same time, your tablet, and even share it on the internet.  The only downside I have run into is that it can overload with strong signals.

The AirSpyHF+ is another good SDR, maximum bandwidth of 768 kHz. It's very sensitive, and a good performer. Also tunes part of the VHF band as a bonus in addition to HF.

There's a few SDRPlay models, I have a RSP1A. Good value for the price, and the wide bandwidth (8 MHz) is useful at times. Covers a huge range, LW/MW/HF/VHF/UHF up to 1700 MHz or so from memory.  I am still getting used to the SDRUno software, which is very powerful with lots of features. As a minor downside, the AGC action can take a little getting used to.

I really like my AFE822x dual channel SDR. They make a single channel version AFEDRI as well. Great value for the money, and a solid performer. Buy direct from Alex in Israel, shipping is cheap, I think it was $24 to the USA.   I use this on the 48 meter Europirate band, and it does a great job. I also use it portable with my laptop as it can be powered by USB, to sniff out RFI sources.  It has an ethernet interface, so you do not need to install USB drivers. I love it. Not sure why the AFEDRI SDRs don't get much attention, they are really solid performers and excellent value for the money. I'd give up all my other SDRs (except the netSDR) before this one.

The netSDR is no longer made, but it's one of the Cadillacs of the SDR field. Solid performer. Built like a tank. No weird effects, it just works, and you can always believe what you see. Super sensitive. No images. It's my workhorse for the 43 meter pirate band, and the radio I turn to daily use on other bands when doing live listening. If you find one for sale used, buy it.
Chris Smolinski
Westminster, MD
eQSLs appreciated! csmolinski@blackcatsystems.com
NRD 545 / netSDR / AFE822x / AirSpy HF+ / KiwiSDR / 670 ft horizontal loop / 500 ft northeast beverage / 270 ft west-south-west beverage / 300 ft south beverage / 43m / 20m / 10m  dipoles / Crossed Parallel Loop

Offline Josh

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Re: RTL-SDR maintenance help needed
« Reply #5 on: May 07, 2019, 1952 UTC »
"Just wondering which one is the most fair one to get. I just need good performance just like my analog radio does."


Keep in mind what Chris said above, but I'll add my own here,
To best support what you intend on doing with an sdr helps determine wich is likely to be capable of what you desire without spending more cash than needed.

If you want to monitor a single channel or narrow spectrum slice at a time, most any sdr will do fine here.

If you want to look at swaths of spectrum on the screen and have multiple vrx open at the same time, you need a sdr and pc capable of that.

Some sdrs offer vrx and huge swaths of spectrum while others don't, the oens that don't sometimes offer outstanding specs in sensitivity and dynamic range, wich can be very important in places like Europe where in the evening the hf environment is crowded with very high signal levels from hfbc and military operations.

In your case, considering your location alone, I'd be looking at the sdrs that offer better dynamic range, meaning they have more than 12 bits of adc. 12 bits is right on the jagged edge of performing admirably in a strong signal environment, more is better.

As to the RTL dongles, they're fun to mess with on hf when you have nothing better, but remember they were designed for v/uhf work and have input filtering optimised for that range, when you use them on hf without a converter that filter is bypassed, reducing the already low 8 bit dynamic range.
Conveniently located near Vincennes Indiana.

Offline Stretchyman

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Re: RTL-SDR maintenance help needed
« Reply #6 on: May 07, 2019, 2021 UTC »
RSP2pro

Simples!

Str.
'It's better to give than receive' so why RX when you can TX!

                            Buy one from me, NOW!

Great discounts on ALL my transmitters if purchased via HFUnderground


                                              ;)

Offline Token

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Re: RTL-SDR maintenance help needed
« Reply #7 on: May 14, 2019, 2355 UTC »
The SDRís I am looking at are the following:

Kiwi-SDR
SDRPlay
HackRF
Win radio pci card
RTL-SDR v2 or v3

Just wondering which one is the most fair one to get. I just need good performance just like my analog radio does.

Of these, and looking at HF performance specifically, the WinRadio will have the best performance.  The G31DDC is the best HF performer in its price category, but the G33DDC is among the best receivers, of any kind, I have ever used.  The G35DDC is better yet, but at several times the already expensive G33 cost it better be.  Stepping back to the hybrid WinRadio offerings, the WR-313 is very good, excellent, however it has a very limited IBW and so the "SDR" features (waterfall display, wide band record, etc) are less useful or lacking.  The WR-315 is also very good, but also has the limited instantaneous bandwidth issues of the WR series.  The WR-305 is more of an entry level receiver, although still quite good.

The Kiwi SDR is at a good price / performance point, but really its forte is its ease of setup for online use.  Not a bad receiver at all, but outside the quick and simple online setup not really a stand out rig.  If you want to place a rig at a location you are not physically at and access it, or you want to make your SDR available for others to use, the Kiwi is king.

If I had to cut down to or pick just one HF centered SDR today for me it would probably be the G33DDC, although I use my RFSpace NetSDR more, I still think the G33 is the better of the two.

RTL-SDRs are so far down my list as to be off the bottom.  They are a tremendous bang for buck, and excellent entry to the field, but frankly, compared to the others you (and other people) have listed they don't belong in the conversation.

But really, you have to decide if you want HF or if you want wider coverage.  Because that will narrow some of the field for you.  If you only want HF, and want peak performance in that region, that becomes a different list than a list that would include VHF/UHF.

T!
T!
Mojave Desert, California USA