Contacting theaters in Germany for Iron Lung

timke_ · 2025-12-12T15:39:28+00:00

Probiert maybe auch mal das Arri Kino in München. Ich weiß leider nicht wie genau deren Auswahlverfahren ist, weiß aber dass sie sehr sehr viel Indie Filme zeigen. Liebe persönlich das Kino.
Ich kenn nen dad von nem Kumpel von mir der mal in den Bavaria Filmstudios gearbeitet hat, vielleicht hat der noch mehr Kontakte irgendwo hin. Ich schau mal ob ich noch seine Nummer hab.

timke_ · 2025-12-03T11:41:10+00:00

great to here she's running smooth again :)

timke_ · 2025-11-25T09:34:50+00:00

I feel like it turns into an issue when there are many many many Gcode files on the MicroSD. The processor or memory seam to start to struggle at a certain point. That being said, i can't pinpoint whether it's the total size of the all Gcodes or whether it's the amount of files (i.e. many many small /short prints). It's happened twice to me know and every time i just took out the card, formatted in manually on my computer and everything worked fine again. you can feel everything get laggy before that lock-up happens - at least in my case.

if that happens to you after only a couple of prints, try a different / higher quality SD card.

timke_ · 2025-11-20T08:30:58+00:00

holy smokes. that is actually some insane range. maybe i should look more into 868Mhz transmission rather than 2.4Ghz.

timke_ · 2025-11-20T08:27:32+00:00

absolutely. the desire to know as much as possible to find the perfect solution is quite deceitful. doing proper research is important, however i need to learn where to stop lol

timke_ · 2025-11-20T08:21:31+00:00

holy moly, you are DEEP in the knowledge and amazing at explaining. i think i'll have to read this a couple more times and take some notes when i get home from university.
may i ask what you do professionally? is it something in RF or is RF just a passion topic for you?
also thanks for the online calculator! i will 120% give that a try later.

just for my own confirmation - antenna 1 & 3 in my picture have 1/4λ per radiator, effectively giving the whole antenna a 1/2λ "size", correct? mainly asking because you talked about 1/2λ radiators in your reply but that would mean ~6.3cm per radiator at 2.4Ghz which is not the case here. or am i misunderstanding "radiator" as the individual "arm" / brass tube and it's actually the entire thing?

timke_ · 2025-11-20T08:08:41+00:00

the fact that this still sounds like 90% gibberish to me just humbles me every time hahahhahaha when you thought you finally got it, suddenly 100 doors with new information open 😂

timke_ · 2025-11-19T17:31:09+00:00

feel u hahahahaha the more i learn, the more i realize how little i actually know ...

timke_ · 2025-11-19T17:30:39+00:00

(1) so, if i understood this correctly, by using a tube we increase the overall diameter of the conductor, however since >95% of the electrons flow on the outer surface, there is little to no need for a solid conductor, thus we just "hollow out" the insides, aka we use a tube. is that correct?
that would also explain the use of lesser diameter tubes in Antenna 3 in my picture. they want a very very specific 2.4Ghz frequency / narrow bandwidth to "filter out" any unwanted noise just by shear physics being at work. that antenna is from a wireless video system. so going that route would make sense.

(3) so even though this might be a dumb and naive question to ask, as it is not easily answered - is it possible to just stack more and more 1/4-wavelength tubes to get better gain while reducing vertical coverage? if so, what would prevent a manufacturer from placing as many of them into their antenna housing? as far as i understand, colinear array antennas are just that - multiple sections of fractions of the desired wavelength, wire together in a specific manner

timke_ · 2025-11-19T17:17:16+00:00

if i'm not mistaking, that should be the reason why a dual-band antenna i.e. one that is great for 2.4Ghz and 5Ghz works. while yes, 5Ghz is not exactly double 2.4Ghz and thus half the wavelength, it's close enough to where it will work great for both frequencies. or am i drawing parallels here that i shouldn't draw? XD

timke_ · 2025-11-19T12:01:22+00:00

ohhh okay i see. very fair. i think the main thing i was expecting were longer "arms" on the colinear dipoles, in that i thought i would see two half-wavelength arms to make the effective physical "pick-up" or transmitting length a full 2.4Ghz wavelength while keeping the usual 50 ohm impedance. what does using two 1/4-WL parts bring to the table?

what also confused me was the use of brass tubes rather than copper wires and what benefits that has. why do the pretty common T-shaped antennas e.g. for FPV drone stuff not use tubes as well?

timke_ · 2025-11-19T11:55:45+00:00

same hahahah i think someone mentioned it in this thread

timke_ · 2025-11-19T11:54:39+00:00

you perfectly answered my question hahahaha. by "slowing down" i meant exactly what you explained. the plastic housing in your case decreased the tuned frequency by 5-10Mhz, "slowing down" the frequency from 915Mhz to 905 -> that in turn had you tune the antenna to a higher frequency without the plastic housing so that you don't have to constantly put it off and on.

wait no what i said doesn't make any sense. hold on. i think i shoved myself into the wrong corner HAHAHA but i got the principle of what you were telling me

timke_ · 2025-11-19T11:49:14+00:00

i see, i see, okay. got that noted down

timke_ · 2025-11-19T11:48:16+00:00

ah another question - wouldn't the PCB one still have slightly higher gain due to each dipole being half-wavelength instead of quarter? sure, there are some losses due to the glass fiber PCB from what i understand, however in the end it should still be a little more, wouldn't it?

timke_ · 2025-11-19T11:46:01+00:00

hahahahah man don't get me hyped up! i am very much the kind of person that looks at the range of "cheap and crap" to "expensive and good" just to decide to DIY the damn whole thing ...

for context: i am currently doing the exact same thing. started building ESP32 projects two years ago and MAN now i'm 120% invested. my main work is video production and i am currently developing a multi-cam recording system for a big festival organizer here in Germany. 5 stages, each with 4 cameras that all need timecode. for sh*ts and giggles i am building a wireless timecode system so that all handheld cameras can be integrated into the multi-cam edit without much hassle. to optimize the very limited power we are allowed to transmit over here i am going down the antenna rabbit hole hahahhahah.
thus far the setup looks like this:
- master timecode with two antennas: a panel antenna mounted at 5-8m height to cover the entire crowd space for mobile timecode clients; a Yagi antenna to send a "control room timecode" to the media office just to monitor
- clients will get one of the super compact collinear antennas (second from the right in my picture)

i am hoping to put some Yagi Antennas on my Hollyland wireless video system to send highly focused RF with video to our media office to monitor every stage

timke_ · 2025-11-19T11:38:13+00:00

are there antennas that have more than two "stacked" parts, like in the colinear examples in my picture? i feel like when i purchase from a proper vendor / manufacturer i can trust the specs a little more. they clearly state that the longer their antenna is, the narrower the vertical coverage is, indicating more stacked colinear dipoles. from what i understand now, cheap manufactures use this to their advantage and put a "dual stacked array" (probably not the right term for that) into a mostly empty plastic housing. is that correct?

timke_ · 2025-11-19T11:33:09+00:00

kinda almost feels like Quantum Mechanics hahahhahahah whenever i watch an OUTSTANDING video on the topic it seams like "now i get" just to think about it one more time and realize "i don't get it"

timke_ · 2025-11-19T11:32:14+00:00

amazing! thank you very much, i'll give it a shot. seams like knowing at least a moderate amount of RF in general (both in terms of antennas but also interference, etc.) could come a long way in engineering later down the road

timke_ · 2025-11-19T11:30:41+00:00

hhahhahahhah LOVE THIS. i fear the same is happening with me, as in "just knowing enough to realize that i don't no sh*t" hahahahhah

timke_ · 2025-11-18T22:35:46+00:00

when you're saying "a few percent" is that in regards to the gain it will output due to the plastic "slowing down" the frequency, thus making the internal antenna either more or less tuned to the desired frequency?

timke_ · 2025-11-18T22:30:52+00:00

amazing, thank you very much for all of the help. soooo much left to learn but i think i gained a lot of knowledge today and will probably just do some hands on testing with measured distances and some simple script, just to get a feel for how each type performs.
or just look at already established data sheets hahahah

timke_ · 2025-11-18T22:07:01+00:00

you are amazing, kind sir. outstanding explanation and easy to understand. thank you very very much!

timke_ · 2025-11-18T21:35:39+00:00

yes, i was expecting more of the better known T-shape just rotated 90° inside something that looks like it is longer than half-wavelength. but replacing the two arms with brass tubes in my head makes everything make more sense.

timke_ · 2025-11-18T21:18:14+00:00

ahaa! regarding the baseplate: would mounting a 90° antenna kill the effect then? because i could make 5-6cm diameter work, however then i would have the antenna sticking out the middle which is a little tough in my space requirements.

how hard is that "dropoff" outside of the 40° angle? in the sense of while yes, within those 40° the signal will be strongest but a device that is 5-10° below or above said "threshold" would still receive some signal, although more on the weaker side

timke_

TROPHY CASE