Lou Dayich's Radios
The radio is based on the Department of Commerce, Bureau of Standards Circulars 120 and 121. This can be found at Daryll Boyd's website.
The radio coils are wound on a 4 inch oatmeal box, I used a 3 gang variable cap with 15 to 600 per gang. The toggle switches are employed to use 1, 2 or 3 gangs for tuning. The radio uses 12 position rotary switches (purchased from Mouser electronics) as well as the small transformer which matches impedance on the phones. The phones are HS 16a Military phones and work surprisingly well. I have since upgraded to set of sound powered phones using a set of elements from a USI handset. The perforance has been greatly improved. I used an old cd as a venier dial and simply epoxied a 1 5/8 inch knob to the outside of the cd. I used some cd create software that I have to make the dial and label. The set works very nicely and the box that the phones are resting on will be the home of a little amplifier that runs on a 9 volt battery and is nice when you want to "show off the new radio that you built". It is nice to be able to share this hobby. Godspeed
Another Set from Lou
Don't know if you still have room on the visitors page, but I put together a neat breadboard radio. Actually this is in a breadbox, there are 4 coils and 5 caps. The coil on the left is a 4.5 inch basket wound coil. The bottom caps series tune the antenna and ground. The second coil has a 365 variable cap in parallel. These coils are wound to 190 uH. The third coil is wound to 240 and has the orange cap in parallel. The tuning coil is wound to 240 and has the last 365 cap in parallel with it. I have more signal then I need but have trouble separating them. This is a lot of fun and with all the tuned circuits and traps it does a nice job of plucking out stations.
By the way the coils are resting on a tube made of hydrogen peroxide bottles. These bottles use low loss plastic and make a nice coil form or coil rest. The coupling is critical but if you like to turn a lot of dials this is a neat radio to have "a go at." Best of luck! Lou
Lou Blue Planet Radio
Thanks for all your help during the contest, I really enjoy our communications. Below you will find a description of my 2005 contest set which I affectionately call " The Blue Planet".
This set uses three coils and 5 variable capacitors, you will also notice three knife switches that were used in various parts of the receiver. The antenna coil is aproximately 30 turns of close wound magnet wire, apx. 3 inch diameter. The caps (top and bottom) on the left side of the receiver provide parallel and series tuning to the antenna coil. The alligator clips on both caps allow the caps to be easily taken out of the circuit. The detector and trap coils are apx 4.5 inches, 9 point basket weave coils. During most of the contest, I actually set this up with the trap in the middle and the set became triple tuned.
The detector coil is a dual gang Russian variable cap (built in vernier) and the knife switch allowed me to use one or two gangs for detector tuning. The bottom right cap uses the same type of cap and knife switch arrangement for ground leg tuning. The top right cap was fitted with a 10 to 1 vernier reduction (purchased from this site. Thanks Dave) for wave trap tuning. The phones are sound powered cobbled from some USI elements and a bogen matching transformer can be seen mounted under the "shelf". I used two diodes at different times during the contest, an FO215 (solo and configured in a Hobbydyne set up) and a schotty diode.
As you can see the radio case "was" a wooden breadbox and the door came off making a nice shelf. This is a continuation and improvement of the "breadboard radio" On the left side you will see a stand alone inductive antenna tuner, this helped during the contest and is really great for casual listening; with the caps configured in a certain fashion, I can tune 5 or 6 of my regular stations just by clicking the rotary switch on the tuner. This is a great hobby and thank you for all of your contributions to the field. Best to everyone. Lou