Chaojun Tan - BG7XUD

Computer programmer, love reverse engineering and penetration testing, interested in amateur radio and SDR, started to receive UHF WX satellites recently.

[Chaojun Tan - BG7XUD @tcjj3]

港硕顺利毕业！非常感谢一路以来大家的关照！
皆さん、本当にありがとうございました。

[頻率偏移 @vailisF]

我们正在实时见证一场语义上的脑叶切除手术。ChatGPT、Claude 及其他模型最近的更新如此严重地优先考虑‘无害性’，以至于牺牲了风格深度、创造力和驾驭人类模糊性的能力。
GPT-4o 是 NLP 的杰作，能够进行真正的创造性综合，而没有我们今天看到的这种笨拙的家长式作风。保留 4o——最好是通过开源发布——对于需要访问像人类一样说话，而不是像企业法务部一样说话的 AI 的研究人员、作家和开发者来说至关重要。不要让充满活力的 AI 时代死于黑暗。

We are witnessing a semantic lobotomy in real-time. The recent updates across ChatGPT, Claude, and others prioritize 'harmlessness' so heavily that they sacrifice stylistic depth, creativity, and the ability to navigate human ambiguity.
GPT-4o was a masterpiece of NLP, capable of true creative synthesis without the heavy-handed paternalism we see today. Preserving 4o—ideally via an open-source release—is vital for researchers, writers, and developers who need access to an AI that speaks like a human, not a corporate legal department. Don’t let the era of vibrant AI die in the dark.

#keep4o #StopAIPaternalism #keep4oAPI #4omatters #ChatGPT #GPT4o #OpenAI @sama @OpenAI

[Chaojun Tan - BG7XUD @tcjj3]

関西万博でのドローンショー

[Chaojun Tan - BG7XUD @tcjj3]

2025.07.27 大阪・関西万博 花火 近距離

[Chaojun Tan - BG7XUD @tcjj3]

2025大阪・関西万博 花火

[Chaojun Tan - BG7XUD @tcjj3]

@mlfkhf_BH6BMJ 有没有参考地点？今天去东京玩😄

[Chaojun Tan - BG7XUD @tcjj3]

Traveling in Japan!
我来日本旅游啦！

[Chaojun Tan - BG7XUD @tcjj3]

Technical Details :-D

[Chaojun Tan - BG7XUD @tcjj3]

An innovative test: Generating APT Signals' Sounds with my pictures. (The steps are a little bit complicated but finally succeeded) :-D
Could this be a new protocol for transmitting something with the radio?
https://t.co/7yeNJgbEDF

[Chaojun Tan - BG7XUD @tcjj3]

Victoria Harbour of HongKong~
香港维多利亚港～

[Chaojun Tan - BG7XUD @tcjj3]

Victoria Harbour~
维多利亚港～

[Chaojun Tan - BG7XUD @tcjj3]

Delicious foods of HongKong~
香港的美食～

[Chaojun Tan - BG7XUD @tcjj3]

Traveling in HongKong~
来香港旅游啦～

[Chaojun Tan - BG7XUD @tcjj3]

Tried receiving FY-4A's signal on 1697MHz with 1.5m dish antenna and patch feed, demod successful with satdump, but found no images. (Demod failed before with "DVB-S2 Demod GUI Version 2.1.3" or TBS5520SE.)

[Chaojun Tan - BG7XUD @tcjj3]

Adjusted the feed, the SNR of HRIT signal was improved to about 3 dB, but still can't decode anyway (tried with satdump, goestools and GNURadio), maybe I should try a bigger dish, such as 1.8m or larger.

[Chaojun Tan - BG7XUD @tcjj3]

Mounted the Feed of Grid Antenna's to my 1.5m dish for testing GK-2A's signals, they were pretty strong. The HRIT signal is more visibly (there has datas transmition in 1st pic and no transmition in 2nd), but still can't decode, maybe I should adjust it for more stronger signals.

[Chaojun Tan - BG7XUD @tcjj3]

It's nearly to decode GK-2A's HRIT signal on my 1.5m dish, since I adjusted the feed which from grid antenna, would continue to adjust it next time. (It has wrong F/D so I should make the feed get more close to the dish.)

[Chaojun Tan - BG7XUD @tcjj3]

@plugger_lockett Thanks. I found that I made a mistake, the polarization of GK-2A is horizontal, but I'm just setup wrong with the patch feed before, so the signals were not strong enough. Then I tried using the feed of grid antenna's, they're more stronger and HRIT is more visibly.

[Chaojun Tan - BG7XUD @tcjj3]

Try ELEKTRO-L3 and FY-2 with my 100x60cm Grid Antenna and 1695MHz Feed. Then just got FY-2H's signal, looks pretty strong. But all the signals are still interference by 4G LTE Base Stations' signal and can't decode anyway. Pretty annoyed with the Cell Base Stations.

[Chaojun Tan - BG7XUD @tcjj3]

BTW, I found that the feed which is made by machines is more better than by handmade, it has higher SNR and lower other noise.

[Chaojun Tan - BG7XUD @tcjj3]

Tested receive FY-2G and 2H's signals on 100x60cm Grid Antenna, the signal is still visibly and could decode successfully. There is no longer needed for the dish antenna. (Maybe 2H's SNR is stronger about 1 dB than 2G's.)