Thanks TOM I appreciate your comments there will be another video on this regenerative receiver soon . It is my desire to Help others in this great hobby just like I was helped by "Elmers" in the past . Back in 1958 While gathering parts for the Twin Plex that I never finished I was stringing an antenna at my parents home . A BIG guy I did not know stopped his car came over and said " Hey Kid what ya doing " I told him I was building a regenerative receiver and was putting up a radio antenna . He said "Do you need any parts " . I said yes a 6SN7 tube the next evening he showed up and handed me a 6SN7 tube and that was how I met W9EPT Smitty who became a very good friend for many years and was one of my Elmers . Right after that someone told me about a BC-348 receiver for sale in town I could afford and I bought that and I never finished the Twin Plex with the 6SN7 . And so this was my motivation to build the Twin Plex receiver now after all these years and see how it works . It has been very enjoyable collecting the parts ,building it and seeing how well it works after what about 60 years . 73 Tom Bob
Update. Finished the SW-3 coil for 40M CW I learned some things first that vernier dials of some sort are really needed for CW tuning CW is very quick and sharp so vernier tuning will help a lot BUT if you are just going to listen to AM broadcast then a vernier dial is not needed just a big tuning knob . Cw reception had hum on the signals this is a problem with using a 120 volt AC power supply . very good filtering is needed to run the Twin Plex from an AC power supply . It worked just fine on Am broadcast but on 40 meter CW the hum was to much . I re-worked the power supply with bigger filter capacitors a single half wave rectifier circuit to supply the 6SN7 with DC filament voltage not real smooth DC on the filament but it works fine . It has a nice CW note now and copy is excellent on CW . I will provide more detailed information on this in a future video with all updates and improvements I am making . The last thing I did was to replace the 10 turn 100K regeneration pot with a common standard pot . I found a 100 K standard pot and tried it and I prefer the standard pot for regeneration to much turning and turning with the 10 turn pot. 73 Bob
Are you aware that Greg, AA8V, has a you tube channel? I met Greg while he was a graduate student at Kent State University, Kent, OH. I remember when he left Kent for a professor position in Frostburg, MD. Later, I worked Greg via CW QRP. Glad you found his receiver design. 73 Terry KB8AMZ
Todd Got it on there at the bottom of the description . I tried it and had to copy and paste it in the web address box at the top of the page it would not work automatically . 73 Bob
Thanks TOM I appreciate your comments there will be another video on this regenerative receiver soon . It is my desire to Help others in this great hobby just like I was helped by "Elmers" in the past . Back in 1958 While gathering parts for the Twin Plex that I never finished I was stringing an antenna at my parents home . A BIG guy I did not know stopped his car came over and said " Hey Kid what ya doing " I told him I was building a regenerative receiver and was putting up a radio antenna . He said "Do you need any parts " . I said yes a 6SN7 tube the next evening he showed up and handed me a 6SN7 tube and that was how I met W9EPT Smitty who became a very good friend for many years and was one of my Elmers . Right after that someone told me about a BC-348 receiver for sale in town I could afford and I bought that and I never finished the Twin Plex with the 6SN7 . And so this was my motivation to build the Twin Plex receiver now after all these years and see how it works . It has been very enjoyable collecting the parts ,building it and seeing how well it works after what about 60 years . 73 Tom Bob
I've been wanting to build a regen for many moons now. Your excellent unit has built a fire under my behind.....I've got to have one. Very nice work.
Very well done sir! I love how you used older components. I very much enjoy your videos.
Update. Finished the SW-3 coil for 40M CW I learned some things first that vernier dials of some sort are really needed for CW tuning CW is very quick and sharp so vernier tuning will help a lot BUT if you are just going to listen to AM broadcast then a vernier dial is not needed just a big tuning knob . Cw reception had hum on the signals this is a problem with using a 120 volt AC power supply . very good filtering is needed to run the Twin Plex from an AC power supply . It worked just fine on Am broadcast but on 40 meter CW the hum was to much . I re-worked the power supply with bigger filter capacitors a single half wave rectifier circuit to supply the 6SN7 with DC filament voltage not real smooth DC on the filament but it works fine . It has a nice CW note now and copy is excellent on CW .
I will provide more detailed information on this in a future video with all updates and improvements I am making . The last thing I did was to replace the 10 turn 100K regeneration pot with a common standard pot . I found a 100 K standard pot and tried it and I prefer the standard pot for regeneration to much turning and turning with the 10 turn pot.
73 Bob
Beautiful job Bob, like what you made and like the idea of using the bread pan!
Thank you Carl this is great fun for me as a retiree and it keeps my mind sharp 73 Bob
Nice build Bob.
Are you aware that Greg, AA8V, has a you tube channel? I met Greg while he was a graduate student at Kent State University, Kent, OH. I remember when he left Kent for a professor position in Frostburg, MD. Later, I worked Greg via CW QRP. Glad you found his receiver design. 73 Terry KB8AMZ
Definitely going to be looking this up.
I love it Bob! Always great stuff... 73 de N9DD
Thanks Tom I appreciate that my friend . 73 Bob
Is the ten turn pot using a reverse biased diode as a fine tuner?
Great job! that was fun to learn about. Can you put the link to that article in the show notes. Thanks.
Todd Got it on there at the bottom of the description . I tried it and had to copy and paste it in the web address box at the top of the page it would not work automatically . 73 Bob
Thanks!
I built the earlier version of the Twinplex published by Lindsay tech books. It uses a #19 tube.