I have seen similar instructive videos on using RG58 coax to wind these chokes and they all seem to ignore the "minimum radius" specification of this coax which is 1.96 inches. Clearly these chokes are winding them to about a 0.5 inch radius. How does the RG58 coax react to that?
FWIW I have never had any identifiable problem with migration of the centre core even with one that was wound nearly 40 years ago. However I am no longer convinced that it is the best way to build common mode chokes, when the turns count is high it seems that interwinding capacitance ruins the performance at the higher frequencies. (I was seeing almost identical results to G3TXQ). My latest versions use twisted pairs as the windings, specifically pairs removed from CAT5-6 cable. These have a nominal characteristic impedance of 100 ohms, so I use pairs in parallel to achieve 50 ohms. I have not operated them at prolonged power of more than a few hundred watts (yet) but the common mode attenuation and bandwidth appear to be better.
A very nice presentation. Most unknow issues get resolved both to receive and transmit.
Clear and beautiful video, thank you very much
Nicely done!
How much power it can be handle using 1 ft240-43 and rg58?
I have seen similar instructive videos on using RG58 coax to wind these chokes and they all seem to ignore the "minimum radius" specification of this coax which is 1.96 inches. Clearly these chokes are winding them to about a 0.5 inch radius. How does the RG58 coax react to that?
FWIW I have never had any identifiable problem with migration of the centre core even with one that was wound nearly 40 years ago. However I am no longer convinced that it is the best way to build common mode chokes, when the turns count is high it seems that interwinding capacitance ruins the performance at the higher frequencies. (I was seeing almost identical results to G3TXQ). My latest versions use twisted pairs as the windings, specifically pairs removed from CAT5-6 cable. These have a nominal characteristic impedance of 100 ohms, so I use pairs in parallel to achieve 50 ohms. I have not operated them at prolonged power of more than a few hundred watts (yet) but the common mode attenuation and bandwidth appear to be better.
Liked and subscribed from Connecticut!
Nice work!
Very good presentation, keep it up, already subscribed. DE VU2TAH.
Well-done. I am really proud of you.
De VU2RZA
Thank you 🙏
@@AniruddhaBokilVU3FML I request you to bring out more such videos. All the best 👍