Tagged: kn0ck

KN0CK HF Upconverting and Direct Sampling RTL-SDR Receiver Store

In previous posts we have featured Marty KN0CK’s popular modified RTL-SDR dongles which have either a miniature built in high quality HF upconverter with amplifier and filter, or an amplified and filtered direct sampling modification applied to them. With these modified dongles you can receive the HF frequencies from 0.5 MHz to 54 MHz. These kits were previously available for sale on a webstore, however that store has since closed down.

Fortunately, Marty’s modified RTL-SDR dongles are still available at http://www.kn0ck.com/HF_SDR/. The HF upconverting dongle can be bought for $75 and the direct sampling dongle at $60. The store page also shows example videos of the performance you can expect.

KN0CK HF Upconverting RTL-SDR Modification
KN0CK HF Upconverting RTL-SDR Modification
KN0CK HF DIrect Sampling RTL-SDR Modification
KN0CK HF DIrect Sampling RTL-SDR Modification

KN0CK and KF7LZE Custom HF RTL-SDR Receiver Revision 5

Update: KN0CKs products are now available at http://www.kn0ck.com/HF_SDR/.

Previously on this blog we’ve seen KN0CK release his custom modified RTL-SDR tuners which have built in upconverters for accessing the HF bands. Revision 5 of the KN0CK receiver is now almost ready for sale, and will be sold over at KF7LZE’s webstore Easy-Kits.com.

Revision 5 promises to be lower priced as it will run using the direct sampling mod instead of using an upconverter which would require more components. It will also use a Mini-Circuits MAR 8 wideband amplifier to improve weak signal performance.

Kn0CK and KF7LZE RTL-SDR HF Receiver Rev. 5
Kn0CK and KF7LZE RTL-SDR HF Receiver Rev. 5

KN0CK Miniature HF Upconverter Rev. 4 Now for Sale

Update: KN0CKs products are now available at http://www.kn0ck.com/HF_SDR/.

The fourth revision of the miniature HF upconverter for the RTL-SDR by KN0CK is up for sale, now that revision three has just sold out. Revision four has a 120 MHz oscillator, and is capable of receiving the 6m band.

Check out the release post over at KF7LZE’s blog, and the product sales page at the Easy-Kits store.

Receiver Opened Up

“Worlds Smallest HF Receiver” (KN0CK Integrated RTL-SDR + Upconverter)

Update: KN0CKs products are now available at http://www.kn0ck.com/HF_SDR/.

Yesterday Marty (KN0CK), developer of the miniature integrated HF upconverter for the RTL-SDR that was recently posted wrote into us with some updates.

Worlds Smallest HF Receiver

The version we posted about recently was his “Production 3” version. He writes to tell us that along with his “Production 3” release he created a 15mm x 15mm “Small Form Factor” radio enclosed in one of the smaller RTL2832 tuner dongles, which is the “Worlds Smallest HF Receiver”. Marty writes

This is a non-preamplified model receiver but has EXCELLENT performance for what you get.  It has become my most favorite receiver to use here in the shack because of its size and performance – not that I don’t like the preamplified models of my receiver line.  I just like how well it performs for such a small receiver – it’s truly unique.

This Small Form Factor Radio has an operating frequency of 100kHz to 54 MHz allowing the 6m band coverage that everyone was so rabid about.  The entire design is predicated on using 0402 SMT parts except for what can’t be squeezed down (the crystal oscillator and the SA612 mixer).  I have built 6 of these radios and have 3 on hand now for sale now.  They retail out at $70.00 because they are HARD to manufacture and are hand-assembled and tested.

If you are interested you can contact Marty at martywittrock_AT_gmail_DOT_com.

Below are some images. The first image shows the size of the worlds smallest HF receiver, the second shows an example of expected HF performance in HDSDR, and the third image shows the upconverter circuit layout.

Worlds Smallest HF Receiver

AM Band Reception from Smallest HF Radio

Smallest HF Radio 15mm x 15mm Circuit Plot

Production 4 Model

In addition to creating the worlds smallest HF receiver, KN0CK has also been working on his “Production 4” model, which has the same performance as his “Production 3” model posted earlier, but is capable of being installed into any RTL2832 DVB-T radio.

This model is now released and will be available for sale at easy-kits.com when “Production 3” is sold out.

Marty writes

The latest production I have is termed as ‘Production 4’ and became a hybrid of my ‘Small Form Factor Radio’ and the existing ‘Production 3’ design.  I took the best of both worlds and then modified the low pass filter to operate into 6m like I did on the Small Form Factor Radio, too.

[The ability to install into any RTL2832 DVB-T radio] was the reason for this final [Production 4] spin – so it could go into the DVB-T radios that incorporated the goofy through-hole capacitors they used in their power supply design (and also cheaper to sell).

I’ve incorporated this new HF upconverter design into the RTL2832/820T model radios, too, and while the performance of the DVB-T stick is not wonderful, it works pretty well with the HF Upconverter I have designed and installed in it.

I must tell you that the RTL2832/820T model radios are the cheapest out there and have 3 goofy through-hole caps in there that made it impossible to install my ‘Production 3’ model HF Upconverter into that radio….Until Production 4 came along… 🙂

The three images below show the circuit layout, upconverter and RTL-SDR dongle together, and upconverter circuit by itself.

Production 4 Board Plot

Receiver Opened Up

Upconverter Board by Itself View1

Future Models from KN0CK and Transmit Capabilities

For the future plans of his worlds smallest HF receiver Marty writes

At this time, I’m going to respin my ‘Small Form Factor’ board to solder the crystal oscillator directly on the board like the Production 4 models do (for awhile, I didn’t have a circuit pads for that oscillator and had to hand wire those on the back of the ‘Production 3’ boards.  Production 4 cleared that issue and now I’ll clean up the Small Form Factor radio the same way.

Finally, Marty talks about his plans to create a transmit (TX) modification to the dongle. He writes

[I] am working toward a transmit side app for this stick – – target is December to make that happen.  I would keep the ‘Production 3’ form factor and then put the TX stuff on the back side of the board.

We look forward to Marty KN0CKs future work, which is likely to be posted about first by KF7LZE, a friend of Marty’s on KF7LZE’s popular blog.

RTL-SDR with HF Upconverter Mod Built In by Kn0ck

Update: KN0CKs products are now available at http://www.kn0ck.com/HF_SDR/.

A few months back we posted about Marty Kn0ck’s plans to sell an RTL-SDR dongle with integrated HF upconverter.

This dongle is now for sale at easy-kits.com.

His RTL-SDR + HF upconverter combination is different to the other combinations posted previously, as Marty uses tiny surface mount components to fit the entire HF upconverter within the dongle casing itself. The result is an RTL-SDR that is capable of tuning between 0 and 30 MHz which goes for $100 USD.

Marty Kn0ck Integrated RTL-SDR

Integrated RTL-SDR HF Upconverter

Over at KF7LZE’s Blog a post about an upcoming integrated HF upconverter using tiny surface mount components has been posted. It is made by Marty KN0CK and will be for sale on KF7LZE’s site soon.

Marty KN0CK developed a very interesting v1.0 HF converter based on surface mount technology that fits inside the casing of an RTLSDR tuner dongle. He’s recently sent me schematics for the revision, which should offer even better performance.

Cropped HF Upconverter Respin 7

Check out the rest of the post here.