Christian Kvikant 🇫🇮

Microwaves and radars adept. Energetic materials chemistry dilettante.

[Christian Kvikant 🇫🇮 @CKvikant]

@AtteKaleva @persut Jos ei tietäisi, voisi kuvitella, että pettymys kohdistuu lähinnä Kokoomuksen siihen siipeen, joidenka kansanedustajat saavat mandaattinsa vihervasemmiston äänestäjäkunnalta.

[Christian Kvikant 🇫🇮 @CKvikant]

@DJSnM Historically, squelch (muting audio when no signal is present) was simpler to implement on an AM carrier.

[Christian Kvikant 🇫🇮 @CKvikant]

@depurjoking @airmainengineer Ferry Permit? What's wrong with an STC?

[Christian Kvikant 🇫🇮 @CKvikant]

@BioTurvaMies @auonsson The interesting thing with passive radar, is that there is a lot of offering, but reference deployments are almost non-existent.

[Christian Kvikant 🇫🇮 @CKvikant]

@2Communications 28dB Gain/0.3dB [email protected] are some pretty good specs.

[Christian Kvikant 🇫🇮 @CKvikant]

@samsam411sam @Rocketsorricket @tt12514 The two sides are probably phase shifted to cater for right hand (RHCP) or left hand (LHCP) reception. So the vias would be offset clockwise or counterclockwise.

[Christian Kvikant 🇫🇮 @CKvikant]

@MehdiHacks What’s worth mentioning here is that the impedance (resistance + reactance) is the same on all ports (hint: width of the traces)... And that a Wilkinson power divider’s insertion loss is minimal at the ¼ wavelength of the signal.

[Christian Kvikant 🇫🇮 @CKvikant]

@mikko Just as a heads-up. Those flying boats’ airframe are made of wood. As an amphibians maintenance mechanic I’d say that’s the very last choice of material, if one intends to uphold these planes' airworthiness/permit to fly, long term.

[Christian Kvikant 🇫🇮 @CKvikant]

@i2cjak Maybe for last 3-4 feet autolanding/collision avoidance as typical output power is only 0 dBm. It will need a PA in between for any real world applications…
Missing their BGT24MTR11 (EoL) with typical output power of 11 dBm.

[Christian Kvikant 🇫🇮 @CKvikant]

@garborg @GrandpaRoy2 Aah, from the original Tg source I see this antenna pair was mounted on the belly, so its an FMCW radio altimeter. Could even be operating at the standard 4.3 GHz band (which have a quarter wave length of 17 mm)

[Christian Kvikant 🇫🇮 @CKvikant]

@GrandpaRoy2 The quarter wave length is about the same as the width of the ceramic GNSS antennas. CRPA tries to filter out non celestial signals. One could assume these are transmitting antennas trying to interfere/sum out horizontally received interfering transmissions at same frequencies.

[Christian Kvikant 🇫🇮 @CKvikant]

@qlavash @kegrocket LOX:IPA

[Christian Kvikant 🇫🇮 @CKvikant]

@DJSnM @cohen_yohana74 FPGAs are chips at risk and in addition to error correction schemes, aerospace grade FPGAs are specifically made radiation tolerant... Could be they’ve found out some vendor’s chips are not on par with specs.

[Christian Kvikant 🇫🇮 @CKvikant]

@CARN0N That's not USB-A. It's an USB 3.0 connector, backwards compatible with USB-A.

USB-C is compatible with and supersedes all older USB standards. However, mechanically it's peace of crap as soldering joints tend to tear up from the PCB -> You're up for $1000 repair at the shop.

[Christian Kvikant 🇫🇮 @CKvikant]

@MakeAugusta Old school energy harvesting.

[Christian Kvikant 🇫🇮 @CKvikant]

@PostNordSverige Finns det någon bra förklaring hur det är möjligt att skicka ett paket med ex. nagellack (begränsad mängd - LQ) från Sverige till Finland och bli debiterad 60,- kronor. Skicka sedan samma burk tillbaka från Finland till Sverige och priset är nästan tusen spänn?

[Christian Kvikant 🇫🇮 @CKvikant]

@MehdiHacks At best, RCS is just an approximation.

[Christian Kvikant 🇫🇮 @CKvikant]

@MehdiHacks Funny, same schematics as in this book, from which I built an FM transmitter, anno ~1984. Had to buy all parts separately from the local radio shop though.
https://t.co/kYmdw4HejF

[Christian Kvikant 🇫🇮 @CKvikant]

@MehdiHacks Hmm.. Phase noise is usually an important factor in oscillators. And if receiving complex modulations, poorly biased bias-tees, that are feeding LNAs could introduce phase noise.

For antenna LNAs most critical is noise figure. And for inline LNAs, the combination of NF and gain.