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- Опубликовано: 13 сен 2024
- RF Sampler RF Tap 3 in 1 Home Build
Schematics www.tonyplaza....
50 Ohm 100Watt go.tonyalbus.c...
50 Ohm 250Watt go.tonyalbus.c...
2W resistors go.tonyalbus.c...
47Ohm2W WirePod go.tonyalbus.c...
BNC Chassis go.tonyalbus.c...
MixedSwitches go.tonyalbus.c...
Alluminium box 120x94x56 go.tonyalbus.c...
Alluminium box 93x38x31 go.tonyalbus.c...
I think you should make some electronics tutorials, you are an EXPERT and we could definitely benefit from your experience :)
Thank you David! , very nice, but that is a bit to much honer, i just took some schematics from internet and build it. glad you enjoyed it!. Tony
I agree... This is more than just a build. Quite a bit of thought went into this, and there's a lot to learn from the experience you have.
What kind of pot you used ?
You continue to impress…
Thank you !
When I was much younger and with minimal training, I bought a spectrum analyzer to tune several duplexers for a public safety organization I belonged to. It was roughly the same price, as it would have cost to send them out for professional tuning.
I was a total IDIOT and connected the output of a Motorola 110 watt UHF (70cm + up to T-Band) P25/analog repeater DIRECTLY to the input of the Rigol 7nit. POOF and even a bit of smoke…🤣
10+ years later, I’m still clueless, but a bit more experienced. 🙂
I have a Telewave 44 watt meter that does not require “slugs”. It has a non-adjustable RF sampling port built in.
They claim The attenuation is variable, but there’s no external adjustment, so I’ve been way to chicken to connect it up.
This project seems ideal.
Thank you sir, that is very nice to read.
sorry you broke your SA .. auwh!
Yes this simple build can save you your equipment...
all the components are in the list below the video (if still available, it is an older video)
Have fun building!
This is just what I was looking for. Thank you for the step by step build of this sampler box, as soon as I get a good VR I'm building my own.
Welcome, glad i could help, also have a look at this one: ruclips.net/video/zqV0aRtgc1c/видео.html
i test it live and in the end i like the resistor only much better, its more flat then with the coil.
Since all die-cast aluminium boxes are actually trapezoidal viewed from the sides, I always think they look much better with the lid as the bottom, and labelled that way up! BTW, I wouldn't put 100W into that tabbed 50ohm resistor for too long, they need a LOT more heat-sinking than that metal box alone can dissipate after some minutes of operation. A big finned heatsink thermally pasted and bolted to the top surface would really help there. The little switch could also be bigger as it may not like the SWR if the dummy load fails or it is accidentally flipped at 100W. Those switches are usually rated 250V at 50Hz, not at HF radio frequencies.
Hi Hector, for high power you indeed use the passthrugh and use a proper dummyload. for small power this is ideal for quick testing.
Why not add this sampler circuit to the inside of an antenna tuner (such as the MFJ Versatuner)? As a matter of fact, I've done that already. By positioning the torroid core around the wire lead to the input to the tuner from the transmitter, the remaining circuitry fits nicely into the Versatuner box. There is plenty of space to mount the pot and sampling jack on the rear of the box. Then, no matter which output is chosen for the Versatuner (dummy load, antenna 1, antenna 2, etc.) an adjustable sampling signal is always available at the sampling jack without siphoning off any of the signal through resistor dividers.
Hi wendell, nice idea
Fantastic video.
Thank you!
Using the short length of wire is what we, in the US, called a "gimmick", which acted somewhat like a capacitor. They were used in some PA neutralization circuits.
Thanks, interesting.. makes sense indeed
I have a 6GHz 100W dummy load. How can I get a proportional sample into the TinySA from the transmission line to get an accurate power measurement?
@@mrtechie6810 I'm not sure, as Bird only makes one with a range from 20 MHz to 1 GHz. When you get into that high of a frequency, things are much different, and I would imagine much harder to design and build.
@@craxd1I want to sample 2.4 GHz for QO-100. It looks like I should use a directional coupler for microwave frequencies.
@@mrtechie6810 You could try to build a pi-type 60 dB attenuator, where a dummy load forms the first 50 ohm shunt resistor in the pi network. To make it a 50 ohm impedance output, the other shunt resistor is also 50 ohms, and the series, which is connected to the 50 ohm dummy load, is 25K ohms, forming a 60 dB attenuator. All resistors are 5 watt, non-inductive, such as a film resistor.
I would use a die-cast aluminum enclosure as small as possible, with a connector to fit a tee at the load, and one for the test lead. Make the resistor connections as short as possible. You would need to check it with a VNA, or similar, for 2 GHz.
A 30 dB attenuator uses much larger resistors to keep a fifty ohm circuit. You would have to purchase a 100 watt attenuator for checking the power of up to 1 kW. 1 kW is about 238 volts, and to attenuate it 30 dB requires something like 60+ watt resistors.
Nice job!
Thanks!
Thanks. I want to make a switchable attenuator
Thankw
Please what is the part number or ohms you used for the variable pot
All items are in the video description.
I love this design! I have been wondering how to do this very sort of thing for HF and VHF ham. For UHF and higher, I'd just use a directional coupler, but that isn't going to work well for VHF and lower. I watched your functional test, too. Would you mind doing a frequency response test of this roughly for the ham bands, say 2 MHz through 150 MHz? Curious about reflections/loss on the through line and the output levels on sample. It seems to function perfectly at 11 meters. I'm curious if the metal film resistors will go inductive in the VHF range, and I'm curious how linear or even usable the torroid output will be over such a broad range (6+ octaves). Love the idea of a mini-antenna bnc port for sampling. Thank you for sharing this!
I just re-watched your second video - I missed the SA tests that you did the first time I watched it! So looks like the fixed output is flat and the torroid, understandably, isn't. I think I may make one with two resistive taps, one fixed and one variable, and maybe substitute a cermet pot for wirewound. I know cermet isn't as rugged or high quality but it should be less inductive.
Thanks You!
Yes after my test i also was thinking of making the variable with resistors and not the torroid. i did use a wirewound 2Watt pot.
wat zijn de waardes van de potmeter, je zegt 47 ohm maar je vermeld 470 ohm verwarrend
Hallo Theo, uit mijn hoofd weet ik het niet,maar ik heb de schemas in de download links in de description. daar staat het vast in. de vaste weesrstanden werkt beter, deze is veel vlakker over frequentie gebied.
Do I see thermal labels there? I'm curious how long these will remain readable if you use the dummy load :-)
Lol .. i totally forgot about that... thanks, yess let’s see...
Would like to built the part with the core only but for power till 1.5KW, which core size and type (43 I suppose) would you recommend. Regards.
Hi, i would not know, but i will advise you the have the simple Resistor divider, as it is a lot more flat on freq response.
See my other video were i test it on the SA
What's the toroid number and what size wire for it, did you use?
Hi Tube-Dude, i just took what i had around. but if you watch the second video on this, where i test it on the SA. you will see, its far from flat, and the resistor are.. i would go for the normal resistors
@@TonyAlbus - Thanks for the reply. How about the wire size?
@@tubeDude48 sorry, it was a while ago...
The big black one, is prob, 1,5/2 mm
Perfectly.
Had to be inserted relay for swich remote.
What's material ferrite coil ???
Hello Natali, it was just something i had laying around.. but watch the 2nd video where i put it to the test, that coil output is not what i like, i will improve it later with resistors, so it is more flat.
ruclips.net/video/zqV0aRtgc1c/видео.html
@@TonyAlbus
You have a big the distance pins and between the components.
Remote coil from the strap cable.
@@nataliartemenko8722 Yes well spotted, but because of the coil, it will not resonant the same on all frequencies.. so not flat.
nice work
Thank you!
looks good,,do you think the mini switch will do 100 watts? will atch the test , then i will make oen,i do have samplers but like you all in one
Thanks Dennis, the switch is 250Volt 2Amp .. 500Watts on 50Hz .. no idea what it will do on HF, but i will not we switching with power on.
Hi Tony,
Nice stuff !!
could you tell us what the make/model value of that resistor in the bottom is ?
and maybe what size toroid coil that is ?
thanks,
kevin rea
lancaster, calif usa
k6rea
Thank you Kevin!, i have now put a list and links to most of the components in the video description.
I have a 100W 6GHz dummy load. I want to get a proportional sample into the TinySA from the transmission line to get an accurate power measurement. Any tips?
This could be it, justonly used the fixed resistors, i my test is was very flat over the frequency range. while the pot was not. ruclips.net/video/zqV0aRtgc1c/видео.html or a professional Bird with 30 or 40 dB output.
ruclips.net/video/i4pF7OIi0KM/видео.html
@@TonyAlbusthanks!
I want to sample 2.4 GHz for QO-100. It looks like I should use a directional coupler for microwave frequencies.
@@mrtechie6810 Okey, well i am not into couplers, i simple never looked into it.
Thanks for sharing! Dank je wel Tony ik ga hem ook maken. Heb je nog een schema van het design zoals je hem uiteindelijk hebt gemaakt? mvg Leo PA1Ldb
Especially in the schematic the resistance values are not totally clear to me, must be me ;-)
Hi Leo, later this week, i will put the schematics in the video discription
Tony
@@TonyAlbus thanks Tony great videos ! Thank you for sharing I ordered some parts in China so will take a few weeks.
@@TonyAlbus Ow another question Tony, did you end up replacing the coil with a bigger one and maybe add more windings? I saw Peter of TRXBench did 12 windings and I think you did the same?
Thank you very much and welcome.
sorry maar ik vind het niet zo'n goeie video!
werkt het? ik heb het niet kunnen zien?
Hallo HobbyBob, er is inderdaad een opvolg video.
@@TonyAlbus Hallo Tony,
ik ben heel toevallig aan het kijken hoe ik zelf zo iets kan doen!
In mijn geval is het voor zo’n Antenne-analyzer NanoVNA maar dat schijnt ook voorzichtig gedaan te moeten worden.
Had zelf zitten denken contactloos en iets met een potmeter…
( voor mij is het voor wat piratenspul om te kijken of ik geen rommel maak! )
blijf meekijken!
Groetjes uit Rotterdam.
RadioRob
@@hobbyrob313 Klikt goed Rob! lekker hobieen... veel plezier!