Achim Vollhardt's Avatar

Achim Vollhardt

@dh2va.bsky.social

physics, hamradio (@amsatdl, #phase4a #qo100 design team member), paragliding

76 Followers  |  68 Following  |  35 Posts  |  Joined: 10.11.2024  |  2.3805

Latest posts by dh2va.bsky.social on Bluesky

Kalkofes Mattscheibe - Geflashte Manager
YouTube video by KalkTV Kalkofes Mattscheibe - Geflashte Manager

youtu.be/yDqyGgaK2Cw?...

24.03.2025 05:28 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
Home Connect-Lieblingsanwendungen der BSH-GeschΓ€ftsfΓΌhrung
YouTube video by FFFlcr Home Connect-Lieblingsanwendungen der BSH-GeschΓ€ftsfΓΌhrung

This commercial made by Bosch managers for the app was super cringe years ago. Was remade by a German comedian.
youtu.be/5EVf9a-nji4?...

24.03.2025 05:27 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Correct, the PRS10 is certainly optimized in that respect.

23.02.2025 17:59 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
Stability and Phase Noise Specifications

John N8UR has a great table of Allan deviations and phase noise of the usual suspects
www.febo.com/pages/oscill...

23.02.2025 13:23 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

I suspect that the LBE-1420 has some numerical oscillator inside(or frac-n PLL)which has 'relatively' high phase noise and sometimes not hit exactly 10.00000 MHz but is a few uHz off. For most applications it is great value for the price but depending on the use case, there are better options.

23.02.2025 13:17 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

In terms of phase noise, the HP10811 (or Z3801) is hard to beat.. we got at work recently a Wenzel ULN, which is also free running but in terms of phase noise even 20dB better than the HP10811. We will be able to measure Allan deviation in the next few weeks, got a new 53100A phase noise analyzer.

23.02.2025 13:17 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

This is because of the internal principle of a Rb oscillator, which runs at 6.8xx GHz and has an internal crystal oscillator locked to it.This setup is not optimized for good short term stability of phase noise but for good holdover performance (keeps time when GPS lock is lost).

23.02.2025 13:17 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 2    πŸ“Œ 0

Excellent comparison and write up, Scott! Some remarks from our (@amsat-dl.org in Bochum) tests over the years:
On short term stability, the HP10811 and the Z3801 outperform the Rubidium oscillators. 🧡

23.02.2025 13:17 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

There will be a time when AI is truly innonative and not a copy of things it can find on the web. Just not yet.

26.12.2024 19:23 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Poor F-35s trying to slow down enough for the DC-3... 🀣

21.12.2024 16:44 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

I was fearing I messed up my node. Glad to see yousorted it out on your side!

21.12.2024 16:24 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

How large is the dish?

12.12.2024 06:56 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Advertise your account with just one image

10.12.2024 15:48 β€” πŸ‘ 4    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Maybe something from local cultural heritage. Goonhilly ground stations are named after the knights of the round table.

09.12.2024 05:01 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

The TT detector station. 4 layers of silicon strip detectors.
The LHC should be offline until April, so this is the time to go underground.

08.12.2024 20:58 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

I installed a part of the LHCb detector in 2006 and took it out again after it fulfilled its duties in 2018 πŸ˜ƒ

08.12.2024 19:39 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Still thinking about an S/X dual band feed similar to QO100 POTY but optimized for DSN.

08.12.2024 19:30 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 2    πŸ“Œ 0

Closely following your construction reports to spot any gotchas. Will follow early next year here with 1.8m.

08.12.2024 19:29 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 2    πŸ“Œ 0

Looks like some very combustible material was inside, glad you are OK.

08.12.2024 19:26 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Welcome here! What is the profile Pic? Looks like a CERN event display... ATLAS? Can't be LHCb, I know these πŸ˜„

08.12.2024 19:25 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

That was exactly my thought.

05.12.2024 05:22 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Swedish Lapland and later in the year Iceland. No surprise that the elders thought these were dancing ghosts.

01.12.2024 15:57 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

The performance model has 925 bhp in launch mode. Totally useless but 😁. Same drive train as Taycan but less expensive.

26.11.2024 19:51 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Try an Audi RS etron GT. So much fun to drive and the design is superb!

26.11.2024 19:28 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Professional car testers in Germany cut a FSD test short because they were too afraid about its demonstrated behavior. Was in TV programme, sadly not YT.

26.11.2024 19:27 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Welcome, John!

22.11.2024 22:25 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Welcome!

21.11.2024 15:42 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

You bet!

15.11.2024 21:58 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
Switzerland Second (official) | Deville
YouTube video by SRF Comedy Switzerland Second (official) | Deville

7 years and still relevant youtu.be/reuJ8yVCgSM?...

14.11.2024 06:58 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Tracked was the right term, thanks!

11.11.2024 19:44 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

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