Just a quick extra note: the resistors I used were indeed metal film resistors. I ended up increasing the size of the copper plate I used and that improved the SWR on higher frequencies ( but not that much ). Meanwhile I also replaced the resistors with 820 Ohms 2W each so the RF tap can handle quite some power now. 0.5W per resistor allows me to use 100W in so for sure 2W is more than enough for my needs. I will try to play a little and see how I can lower the SWR on the higher frequencies though, if not I will simply keep it for HF only as there works like a charm. Now with the new resistors my attenuated signal is at -39.9dB with the new 3 x 820 Ohm resistors. 73, YO6DXE.
That makes two of us 😄 I didn't know either. And I banging my head on the walls how to do something not to use RF attenuators 😅. Glad it works. 73, YO6DXE.
ha ha nice box for this project😁. i have antenna switch in same box but after some time it got oxidation on surface. good luck bud and 73!😊 (its me alex 4l1lat, just another account😂)
Alex just clean it with sandpaper then spray it with two three layers of clean varnish. It will look great and stay that way too 😄😄. 73, YO6DXE. P.S. I won't bother for this box as is just temporary, it will not have time to oxidate.
@ალექსანდრელაბაძე for QRP those will work. For bigger power not so much. In the second version I will try the no resistors version as I described at the end of the video. I think that one will perform better.
Prima,selbstgelötete HF Dichte Leiterplattengehäuse.Habe ich früher auch so gemacht.Bin alter Elektronik Bastler.Von Wehrmachts Raumladetetroden bis BF245 Audione,Verstärker bis bugettbrigade Eimerketten Echos kenne ich alles.bis russische Bleistiftröhren💖😏🤷🙄🙄🙄😂🦊
Ohhh, es ist schon eine Weile her, seit ich das letzte Mal ein Gehäuse aus PCB-Material gebaut habe. Ich bin froh, dass es ganz gut geworden ist, da ich es in Eile gemacht habe. Was Röhrenprojekte betrifft … die habe ich noch nicht gemacht. Ich hoffe, dass ich dieses Jahr auch die Zeit habe, einige davon zu bauen. Ich habe den Traum, einen einfachen CW-Sender mit Röhren und vielleicht einem Empfänger zu bauen, um sie zusammen zu verwenden. Vielen Dank fürs Zuschauen. Grüße aus Siebenbürgen. 7, YO6DXE. PS: Entschuldigen Sie mein schlechtes Deutsch, Google Translate ist nichts für mich (ha).
Thank you as well for watching and for the comments Camille. Good luck with the antenna project. If these days it will stay warm I must remake mine as well. 73, YO6DXE.
Haha yes indeed. The amplification factor is not so great as the plastic ones have, but it seems more stable and... I can use a proper heatsink on it 😄.
@W1RMD I remember the EFT germanium tranzistors... I used those in the original design of the Sputnik receiver for the audio amp... 😄... almost 30 years ago when I tried building the first one that didn't work 😅.
Because I have a personal problem with anything that is SMD and I just hate them 🙈. Anything that is SMD or software / firmware based ( digital technology basically ) 😁. For that reason I prefer old school components and analog circuits only 😁. Is more like an unwritten rule for the DX Explorer projects to be as analog as possible 😁. 73, YO6DXE.
@@dxexplorer Still you probably want to avoid the spiral cut metal film resistors as they will have noticeable inductance at RF. There are companies that still sell carbon composition resistors or you could use low inductance precision flat film resistors (lots of $). You could perhaps design this with SMD components on PCB with two standard shielding cans on the front and back with SMA connectors soldered to the edge of the board.
@KallePihlajasaari No SMD components allowed in my circuits 😁 ... rule number one on this channel haha. No SMD, nothing with firmware / software ... all old school analog. Doesn't have to be perfect as long as it works and doesn't create interferences 😁. About metal film resistors... not sure. As far as I know... they are the most recommended for HF. But out of curiosity ... I will try to build the version I was talking about towards the end of the video as well... no resistors needed for that one so it should perform better. 73, YO6DXE.
They are really tiny. Those are actually little spacers that you use between PCB boards. I used a tiny USB powered soldering iron set at 420 Celsius degrees and a bigger tip compared to the regular one that I use for soldering components. I think the spacers are made of brass so I just used a bit of sandpaper on them in advance and they were pretty easy to solder actually. 73, YO6DXE.
a 40db tab is nice, but remember, rubbish in, rubbish out. The way this s build works well for DC erm short wave and maybe 6m but for serious VHF UHF work it is useless. The inductances in the resistors are far to high and putting them in a long chain with long leads is poor RF construction. I have build units that are flat to 1GHz but they need to have real RF construction practices not flying leads. At a minimum replace the 2 100ohm resistor at the test output end with 2 size 805 100ohm surface mount resistors soldered directly to the jack. You can't make accurate measurements especially harmonics if your test equipment isn't accurate.
I only plan on using this for HF as clearly it doesn't do a good job on VHF or UHF. On SMD... not allowed in my constructions. But towards the end of the video I am talking about another version I am working on that should be fine all the way... no resistors for that one of any kind. For HF it does do a decent job so far. That is all I trust it to do 😁. 73, YO6DXE.
73 my friend, YO6DXE. I will go now and watch the video. P.S. I am back. Ohhh yes I remember I watched it. I could not find the potentiometer to build the same version so I opted for the one I built instead 😄
@EI6DP I am searching now as I found some small values but the multiturn versions at 2W so that is good. Now I try to see if they have smaller values than 100 Ohms. Some store here in Romania.
Just a quick extra note: the resistors I used were indeed metal film resistors. I ended up increasing the size of the copper plate I used and that improved the SWR on higher frequencies ( but not that much ). Meanwhile I also replaced the resistors with 820 Ohms 2W each so the RF tap can handle quite some power now. 0.5W per resistor allows me to use 100W in so for sure 2W is more than enough for my needs. I will try to play a little and see how I can lower the SWR on the higher frequencies though, if not I will simply keep it for HF only as there works like a charm. Now with the new resistors my attenuated signal is at -39.9dB with the new 3 x 820 Ohm resistors. 73, YO6DXE.
another great project! Love the enclosure too 73 my friend
Thank you so much my friend. Is a bit long but I tried to explain the best I could what I understood from building this 😄. 73, YO6DXE.
@@dxexplorer You explained it very well 😄
@alanuk8677 😅😅😅🙏
Very cool! I didn't know it was this easy to build an RF tap
That makes two of us 😄 I didn't know either. And I banging my head on the walls how to do something not to use RF attenuators 😅. Glad it works. 73, YO6DXE.
Very nice video! Looking forward tot he next one!
Thank you so much for watching. 73, YO6DXE.
Nice work! Thank You!
Thank YOU as well for watching 🙏 73, YO6DXE.
Looks good buddy! 👍🏻
Ohh thanks so much. I am so happy I made it. It changed my world 😄😄. 73 buddy.
Cool design,I like it ❤
I want to test the second version as well see how that performs.
Nice, I like it!
It saved me about 600 euros as that was the total cost of good quality RF attenuators I needed that could handle the power I want 😄.
ha ha nice box for this project😁. i have antenna switch in same box but after some time it got oxidation on surface. good luck bud and 73!😊 (its me alex 4l1lat, just another account😂)
Alex just clean it with sandpaper then spray it with two three layers of clean varnish. It will look great and stay that way too 😄😄. 73, YO6DXE. P.S. I won't bother for this box as is just temporary, it will not have time to oxidate.
@dxexplorer by the way i know you don't like smd and stuff but smd resisors might be good choice for this project. you can try them on second version
@ალექსანდრელაბაძე for QRP those will work. For bigger power not so much. In the second version I will try the no resistors version as I described at the end of the video. I think that one will perform better.
@@dxexplorer yeah you are right. okay than waiting for a new video ❤️
I am also really curious about how that one will perform 😄. 73 buddy.
Prima,selbstgelötete HF Dichte Leiterplattengehäuse.Habe ich früher auch so gemacht.Bin alter Elektronik Bastler.Von Wehrmachts Raumladetetroden bis BF245 Audione,Verstärker bis bugettbrigade Eimerketten Echos kenne ich alles.bis russische Bleistiftröhren💖😏🤷🙄🙄🙄😂🦊
Ohhh, es ist schon eine Weile her, seit ich das letzte Mal ein Gehäuse aus PCB-Material gebaut habe. Ich bin froh, dass es ganz gut geworden ist, da ich es in Eile gemacht habe. Was Röhrenprojekte betrifft … die habe ich noch nicht gemacht. Ich hoffe, dass ich dieses Jahr auch die Zeit habe, einige davon zu bauen. Ich habe den Traum, einen einfachen CW-Sender mit Röhren und vielleicht einem Empfänger zu bauen, um sie zusammen zu verwenden. Vielen Dank fürs Zuschauen. Grüße aus Siebenbürgen. 7, YO6DXE. PS: Entschuldigen Sie mein schlechtes Deutsch, Google Translate ist nichts für mich (ha).
very very nice video . thanks you for content 73 F4LPM
Thank you as well for watching and for the comments Camille. Good luck with the antenna project. If these days it will stay warm I must remake mine as well. 73, YO6DXE.
@@dxexplorer Thanks you
@F4LPM 🙏🙏🤗
Long live metal can 2N2222's!
Haha yes indeed. The amplification factor is not so great as the plastic ones have, but it seems more stable and... I can use a proper heatsink on it 😄.
@@dxexplorer I never considered the heat sink (duh!). I just like its nostalgia.
@W1RMD I remember the EFT germanium tranzistors... I used those in the original design of the Sputnik receiver for the audio amp... 😄... almost 30 years ago when I tried building the first one that didn't work 😅.
Why use the metal film resistors which actually are "wound" and not SMD resistors which are flat pieces and have better high HF characteristics?
Because I have a personal problem with anything that is SMD and I just hate them 🙈. Anything that is SMD or software / firmware based ( digital technology basically ) 😁. For that reason I prefer old school components and analog circuits only 😁. Is more like an unwritten rule for the DX Explorer projects to be as analog as possible 😁. 73, YO6DXE.
@dxexplorer 😮
@paulcohen1555 😁😁 it's a long story hehe.
@@dxexplorer Still you probably want to avoid the spiral cut metal film resistors as they will have noticeable inductance at RF. There are companies that still sell carbon composition resistors or you could use low inductance precision flat film resistors (lots of $).
You could perhaps design this with SMD components on PCB with two standard shielding cans on the front and back with SMA connectors soldered to the edge of the board.
@KallePihlajasaari No SMD components allowed in my circuits 😁 ... rule number one on this channel haha. No SMD, nothing with firmware / software ... all old school analog. Doesn't have to be perfect as long as it works and doesn't create interferences 😁. About metal film resistors... not sure. As far as I know... they are the most recommended for HF. But out of curiosity ... I will try to build the version I was talking about towards the end of the video as well... no resistors needed for that one so it should perform better. 73, YO6DXE.
Im wondering how you soldered the nuts to the PCB for screwing in the top. Did you use a regular soldering iron or something high power?
They are really tiny. Those are actually little spacers that you use between PCB boards. I used a tiny USB powered soldering iron set at 420 Celsius degrees and a bigger tip compared to the regular one that I use for soldering components. I think the spacers are made of brass so I just used a bit of sandpaper on them in advance and they were pretty easy to solder actually. 73, YO6DXE.
❤❤
73 and thank you for watching.
a 40db tab is nice, but remember, rubbish in, rubbish out. The way this s build works well for DC erm short wave and maybe 6m but for serious VHF UHF work it is useless. The inductances in the resistors are far to high and putting them in a long chain with long leads is poor RF construction. I have build units that are flat to 1GHz but they need to have real RF construction practices not flying leads. At a minimum replace the 2 100ohm resistor at the test output end with 2 size 805 100ohm surface mount resistors soldered directly to the jack. You can't make accurate measurements especially harmonics if your test equipment isn't accurate.
I only plan on using this for HF as clearly it doesn't do a good job on VHF or UHF. On SMD... not allowed in my constructions. But towards the end of the video I am talking about another version I am working on that should be fine all the way... no resistors for that one of any kind. For HF it does do a decent job so far. That is all I trust it to do 😁. 73, YO6DXE.
Very nice project, design and workmanship. Well done. This is the one I have built. th-cam.com/video/RLwZFlP9wr8/w-d-xo.html
73 de Ger
73 my friend, YO6DXE. I will go now and watch the video. P.S. I am back. Ohhh yes I remember I watched it. I could not find the potentiometer to build the same version so I opted for the one I built instead 😄
I can't remember where I bought the potentiometer from, possibly from FARNELL
@EI6DP I am searching now as I found some small values but the multiturn versions at 2W so that is good. Now I try to see if they have smaller values than 100 Ohms. Some store here in Romania.