einfach_orangensaft
@einfach_orangensaft@sh.itjust.works
- Comment on thank u, next💜 13 hours ago:
bruh
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those are all easy sizes
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anal should never be pain, if it is u doing it wrong
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the chrome layer on cheap chinese metal plugs is probably toxic
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- Submitted 1 day ago to [deleted] | 2 comments
- Submitted 5 days ago to [deleted] | 6 comments
- Submitted 6 days ago to [deleted] | 0 comments
- POV: you are a symmetrical balanced antenna getting impedance matched to a unbalanced transmission linesh.itjust.works ↗Submitted 6 days ago to amateur_radio@lemmy.radio | 0 comments
- POV: you are a symmetrical balanced antenna getting impedance matched to a unbalanced transmission linesh.itjust.works ↗Submitted 6 days ago to science_memes@mander.xyz | 0 comments
- Comment on Man accidentally gains control of 7,000 robot vacuums 1 week ago:
WRONG.
That thing is in your wifi, it probabl has bluetooth too.
It knows the pattern of other devices in your wifi comming and going. It could even grab metadate of every traffic in your wifi. It probably has a temperature sensor (knows when you open your windows). It probably has a movement sensor hence beeing able to grab vibration data…like do you walk around, when, how much, more than one person.
It could also act as part of a DDoS attack or be used as a domestic ip proxy.
- Comment on Consumerism ahhhhh moment 1 week ago:
Its over 1.3 Trillion per year by now, thats more than the Military budget of the usa. You could buy about 80 aircraft carriers with that. Every year.
- Submitted 1 week ago to amateur_radio@lemmy.radio | 3 comments
- Comment on 3D printed motorized variable capacitor, butterfly-trombone hybrid (also question on dielectric losses in capacitors) 1 week ago:
but try to introduce as many voids as possible
ok, so the next version gona have a air gap then
tapering end of side plates into a triangle shape
great idea, gona add that to the next version too
tapering end of side plates into a triangle shape
thought about that too, the capacitor kinda has long leads on it, they could act as circumference extensions for the loop, i tryed shortening the loop a bit and it improved the SWR a bit, i now managed to get it down to 1.46 at 27mhz (before loop shortening it was 2.6). sadly that seams to be the limit of what shortening can do. Now got a SWR of 1.05 at 31,58Mhz…hope the next iteration of the capacitor moves that down to 27Mhz
- 3D printed motorized variable capacitor, butterfly-trombone hybrid (also question on dielectric losses in capacitors)sh.itjust.works ↗Submitted 1 week ago to amateur_radio@lemmy.radio | 3 comments
- Submitted 2 weeks ago to [deleted] | 2 comments
- Comment on Series coax stub capacitors for more precise loop antenna tuning 2 weeks ago:
Good point with the copper sulfide, that wasnt on my mind at all, if i try ill put a protective layer between the braid and the tire rubber
Yeah i heared about the skin effect in aluminum being much shallower than in copper negating the better conductivity of copper, but i didnt found aluminum braids.
On the point of braids, i was thinking that would probably work well since the shielding in coax is also copper braid and many loops are made out of coax, but big diameter coax cant be folded as good due to the core, so i was thinking…maybe just use the shielding and no core at all.
You are right with the dipole, that would probably be the most sane solution. But i cant get the idea of a inflatable loop out of my head now…
- Comment on Series coax stub capacitors for more precise loop antenna tuning 2 weeks ago:
i thought about a bicycle rim :D but i kinda wana keep this a mobile setup…
i have been thinking about inflatable loops recently, sadly i was only able to find a singular example of those (some guy slapping some aluminum foil onto a inflatable swimming tire and it didnt work that well).
My idea would be to take some copper braid sleeve (5cm diameter) and put a inner bike tire thru that. As far as i can tell nobody has tryed that before…and i keep wondering, if i add a small electric pump to the setup i could maybe tune the loop by inflating and deflating it while using a non variable capacitor.
- Comment on Series coax stub capacitors for more precise loop antenna tuning 2 weeks ago:
Yeah i am planing to build a remote controlled coax capacitor eventually (probably something like this: …dxfreun.de/…/Abstimmbereich_MagLoop.jpg ) but right now i am still waiting for some parts to make that happen.
The additional high voltage durability of the serial coax capacitor is nice, (should be now 5kv, since a single RG58 has 2.5kv) but i doubt i gona need that with my 4W Tx ^^
- Submitted 2 weeks ago to amateur_radio@lemmy.radio | 7 comments
- Submitted 2 weeks ago to amateur_radio@lemmy.radio | 1 comment
- Submitted 3 weeks ago to science_memes@mander.xyz | 25 comments
- Comment on 50ohm goes brrrrrr 3 weeks ago:
i might be wrong here but i think a dummy load is different from a terminator, they both 50 ohm, but a terminator is more like a connector cap, while a dummy load is designed to dissipate heat and can often take many watts of power over extended time without starting glow
- Submitted 3 weeks ago to amateur_radio@lemmy.radio | 0 comments
- Submitted 3 weeks ago to science_memes@mander.xyz | 17 comments
- Comment on NanoVNA vs. Loop antenna SWR testing [Question] 3 weeks ago:
Ah yeah sad, southern germany is a bit far away (besides maybe during high solar activity but even they the skips may fly just right over). Thx for doing some calculations, on the safety distance aspect of it, i kinda assume the psychological effect (knowing that u in the RF near field) is probably bigger an the real effect of 4W of RF heating…and i probably just hallucinated the slight metallic taste in my mouth after 1min of keying down while tx testing (my brain do be like that sometimes).
- Comment on NanoVNA vs. Loop antenna SWR testing [Question] 3 weeks ago:
My repositioning the primary loop i managed to get the SWR down to 1.5 :D
I just hoped i aint cooking my insides when transmitting while sitting next to the loop antenna, a online calculator said at 4W i should keep at least 13cm distance from the antenna, but that was for a dipole not a loop…i need a longer feedline to get some distance…
I currently at berlin/brandenburg area, i kinda dont think i will be able to make long distance connection till i upgrade my radio to one that supports SSB tx with 12W (AE5900 eventually i hope). Long term i hope to manage to get a setup that allows me to join the europe wide JS8CALL network on 27.245Mhz. JS8CALL supports message forwarding over other nodes, a bit like meshtastic, i heared of people who managed to comunicate to australia via JS8CALL using multiple forwarding nodes, it is very slow tho due to using the same mode as FT8
- Comment on This is my 6,000th post on Lemmy. It's been great eating beans and learning how not to poop for 3 days with you guys! Brb, gotta send my weekly nudes to the admins 3 weeks ago:
6k and thats probably just counting the primary account lol, great work!
- Comment on Build my first magnetic loop today, holy sh.. 3 weeks ago:
I can feel this meme resonating with me
- Comment on NanoVNA vs. Loop antenna SWR testing [Question] 3 weeks ago:
I love the word Mantelwellensperre, peak german language :D
I build a Air-Core choke from a part of feed line right below the antenna now, and got some slight improvements.
I will try to improve the feeding loop position to see if it gets the swr down a bit more. By now i am already quite happy with the antenna, during a test i managed to make a ~15km Thor8 connection while the antenna was still inside the house (with 4W AM Tx and the receiver in SSB/USB).
- Comment on NanoVNA vs. Loop antenna SWR testing [Question] 4 weeks ago:
This is my capacitor (RG58):
I dont have ferrite beads right now sadly, but i will try to make a Air-Core choke from parts of the coax feed line, maybe that helps.
If i would use a balun between feed line and antenna, i need a 1:1 balun i assume?
I will try to find the frequency where the impedance gets real. Also gona try to maybe build a variable capacitor from 2 metal pipes going into each other depth regulated by a screw, but i mostly wana use this antenna on a single frequency so i hope i dont need much adjustment.
- Comment on NanoVNA vs. Loop antenna SWR testing [Question] 4 weeks ago:
Here is the measurement with smith chart:
There is 2m of BNC RG58 coax between the antenna and the NanoVNA. I calibrated the NanoVNA without the coax line because i was under the impression the line to the antenna is considered part of the radiating system and hence should not be calibrated out. But here is the reading with the coax line to the antenna calibrated out:
- Comment on NanoVNA vs. Loop antenna SWR testing [Question] 4 weeks ago:
Thank you for your answer!
I think i found the root of my problem, the scale settings on the NanoVNA where wrong, to a point where the super slim SWR dip of the Loop was just not drawn on the graph for lack of data points at this point. I changed the scale and was able to see the dip, then tune the coax stub to the frequency i wanted. Now it claims to have a SWR of 3.8 near the frequency i want to use:
But i am still a bit confused, the yellow number left of the SWR reading, i assume that is the scale? or does it mean a SWR of 6.125:3.8?
- Submitted 4 weeks ago to amateur_radio@lemmy.radio | 18 comments
