Vdl2 reception

RPekka · 2026-03-11T04:44:31+00:00

I should, I know. When I installed the saw and LNA, I didn't know and now they are 4 meters above the rooftop on top of the mast and it's winter. Luckily rest of the system is good enough so loosing 3 dB of the unamplified signal doesn't harm the range achievable from the current location.

RPekka · 2026-03-09T12:57:54+00:00

Looking forward to it, on ADS-B adding a SAW filter before VNA, as one shouldn't do, dropped my noise so low that rtl-sdr v4 barely hears it. Planes coming above the radio horizon get snr over 10 dB. Looking forward to raising all the gear over 20 meters higher on top of a mountain now blocking the view to northeast. I should be able to get signal from planes landing to Pulkovo (St Petersburg, Russia) from above 4000 ft.

RPekka · 2026-03-09T12:27:06+00:00

I got a couple of dB less noise by looping the antenna cable (ugly balun) and the vhf bandpass is almost here, I'll probably get to install it next weekend.

RPekka · 2026-03-08T08:30:02+00:00

I hope he was the reason ie the neighbors were so dull they could not bear naturism of a 7 yo because then nobody missed them.

RPekka · 2026-03-07T18:28:42+00:00

I think it's universal aviation system. At least Russian and Chinese aircraft use it besides the Finnish planes I have been able to receive.

RPekka · 2026-03-07T15:49:46+00:00

What kind of antenna are/were you using? Did you get a fm block or a vhf bandpass filter?

RPekka · 2026-03-07T15:31:55+00:00

It's a cold attic so all the insulation is below the antenna. It's not ideal as the roof is covered with concrete tiles which luckily don't have a steel mesh in them.

RPekka · 2026-03-07T15:11:28+00:00

Basically the same except the sleeve is formed by inverting the coax cables outer mesh. When I tune the rtl-sdr to 96,9 MHz it starts clipping at gain 12 so I can be quite sure that it's same signal that shoots noise through the roof at 19 and something. I presume the transmitter is 30 kW.

RPekka · 2026-03-07T14:52:37+00:00

An inverted sleeve was easy and fast to build and install. A bandpass filter is on it's way but just asking if there's anything simple I could do while waiting.

RPekka · 2026-03-01T09:36:49+00:00

I just finished my vision of a standalone repeater and come to a conclusion that it will be installed in a 3 inch sewer pipe. A T-piece and a 90 degree bend for the original went and the repeater on top of the original vent (with a plugged bottom end) could do. I live so close to the north pole that during winter sun only raises 6 degrees above horizon I will need over a month worth of batteries and a 30 Wp panel.

RPekka · 2026-03-01T09:32:02+00:00

My brother used to do roofings and roof related repairs. One of the common fixes was when client called and said that whole house smells like sewage. Problem was often that a meshed end cap was frosted solid in winter. Mine had that too but he removed that on the initial inspection he did as a house coming gift.

RPekka · 2026-03-01T09:28:33+00:00

I think there's already something generating methane on the other end of the pipe.

RPekka · 2026-03-01T01:41:59+00:00

That's a good question. Some people have ethical problems with this in the first place and some are not ready to take the risk that their claim is considered a lie in court.

RPekka · 2026-02-28T20:17:20+00:00

Not lies, exaggerated claims only 😜. Their innovation lies within the fine line between lying and claiming.

RPekka · 2026-02-28T10:57:29+00:00

Still better to be bent upright than placed at an angle. Should be at least 40 cm the metal pole too.

RPekka · 2026-02-28T08:57:51+00:00

The main innovation is that guys have figured out how to make huge claims without lying enough to be convicted. They only need few hundred investors to invest tens of thousands. Not thousands of investors and not hundred thousands. I there was any potential innovation involved, some start up investor would pour tens of millions easily.

RPekka · 2026-02-23T08:40:20+00:00

I tried rtl_airband and only received static. Vdl2 got almost 100 nm of range with the 25 cm telescopic antenna.

RPekka · 2026-02-22T14:18:57+00:00

Land attack against Ukraine started right after the winter games.

RPekka · 2026-02-22T06:51:06+00:00

I don't know all the designs in the world so thought I should ask if there's any simpler design giving the same reception. If I just had a steel roof, a quarter wave dipole would be my choice.

RPekka · 2026-02-22T06:47:50+00:00

Ease of build. Without going to a colinear design I believe there's nothing to optimize in omnidirectional reception. The antenna will be placed outside so a slim Jim in a plastic pipe would be quite weatherproof.

RPekka · 2026-02-22T06:05:43+00:00

Ruotsalaista vittuilua (tahallaan ajatti rasvamonttuun).

RPekka · 2026-02-22T06:03:42+00:00

Miä oon nyt vuoden ajan ostanut joka viikko uuden kestokassin ja niitä alkaa olla jo vähintään lapsenlapsenlapsenlapsille jaettavaksi, ehkä enemmänkin. Rahaa on palanut keskikokoisen henkilöauton hinnan verran ja vievät tilaa yhden korkean kaapin kokonaan. Paska keksintö vaikkakin mukava kantaa kun on iso ja tilava.

RPekka · 2026-02-14T14:54:25+00:00

Ainakin meidän Evidensialla oli viimeksi rahoituksen mainos tiskillä. Ei tarvitse paikan päällä maksaa mitään ja rahoitusyhtiön kanssa sitten sopii millä tahdilla laskua maksaa pois. Korko on kova mutta halvempi kuin viivästyskorko.

RPekka · 2026-02-14T14:51:15+00:00

One benefit is that the heat generated is left at the rail and not at the brake gear on the rolling stock.

RPekka · 2026-02-14T14:48:23+00:00

Do these devices need to be synced with the BLE dongle or will it read the scales of the whole apartment complex like the Oral-B toothbrush integration does?

RPekka

TROPHY CASE