tag:blogger.com,1999:blog-3380839830287420877.post6366312458047834744..comments2024-03-26T07:29:36.610-07:00Comments on VE7SL - Steve - Amateur Radio Blog: Loopstick Magic And The CR-1 CloneSteve McDonaldhttp://www.blogger.com/profile/06229640265009249231noreply@blogger.comBlogger8125tag:blogger.com,1999:blog-3380839830287420877.post-18102246910252341182024-01-22T17:15:27.702-08:002024-01-22T17:15:27.702-08:00When coupling two coils I like to keep the directi...When coupling two coils I like to keep the directions oriented the same ... so if coil #1 has its right end grounded then coil #2 is oriented so that its right end is grounded. It may not make a lot of difference as I've never checked compared it the other way. As well, make sure both coils are wound in the same direction. That may not be important as well in circuits like this as compared to a coil in an oscillator. Also, there's nothing to be gained sensitivity-wise by grounding the detector coil's end so if you leave it un-grounded (but still connected to the capacitor), then there's no dilemma as to which end to ground. In some circuits though, you may see some hand-capacity effects with the capacitor frame un-grounded.Steve McDonaldhttps://www.blogger.com/profile/06229640265009249231noreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-87576232611964281252024-01-22T16:33:04.010-08:002024-01-22T16:33:04.010-08:00I have a question on the “dot” convention/ polarit...I have a question on the “dot” convention/ polarity. I am winding two individual coils to slip over a 1/4” form with two slugs. Does it matter which winding lead goes where? In other words if these two coils are loosely coupled as a “transformer” then on the detector side it seems it must matter which lead of the second winding goes to ground so that “peaking” one side supports the other side? It didn’t matter in the original Heathkit because the coils were pre wound on the form and terminated. You just followed the directions on which lead to wire where. <br />Any suggestions would be welcomed!<br />Thank you<br />351351Mustangnoreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-30925068673348338842024-01-10T22:40:49.858-08:002024-01-10T22:40:49.858-08:00Can you point me to one directly? That would be wo...Can you point me to one directly? That would be wonderful news. I think most of the Rocket Radios were from Japan back in the 50sSteve McDonaldhttps://www.blogger.com/profile/06229640265009249231noreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-1056246264665370842024-01-10T21:18:33.481-08:002024-01-10T21:18:33.481-08:00You can still buy those rocket radios. They are m...You can still buy those rocket radios. They are made in China (probably always were) and they are still cheap. Try looking for them on Alibaba or Ali Express. <br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-36511781279717563002020-02-15T11:19:29.091-08:002020-02-15T11:19:29.091-08:00That rocket radio triggered a fond memory of a uni...<br />That rocket radio triggered a fond memory of a unique crystal set I had around 1960. It was made to resemble a "satellite". It was a round yellow sphere... somewhat larger than a baseball. It had "legs" in a tripod arrangement, so it could sit without rolling away. Out of the top of the sphere, was a threaded brass rod with a red ball attached at the end. That was for tuning. Out from the ball were two "wires". One was the crystal heaphone pair, the other was a length of wire that had an alligator clip on the end, which served as the antenna connection. I remember clipping that wire to the metal wire frame (it held the shade in place) of a table lamp, next to the incandescent light bulb. I could sit in a chair along-side the lamp and listen to local radio. I could tune the radio by twisting the red knob... permeability tuning.<br /><br />I wish I still had that unique little radio. Of course, like most of us experimenters, I ended up taking it apart for whatever reason seemed good at the time, and the rest of its story is lost to memory.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-6431415437555324792020-02-11T15:47:32.429-08:002020-02-11T15:47:32.429-08:00Hi Dan. I hope you can dig out some of those old l...Hi Dan. I hope you can dig out some of those old loopsticks as they are pretty hard to find nowadays. The key to selectivity is the coupled antenna tuner (series tuned) as it makes a huge difference. My PN dials came from local hamfests mostly and one on e-bay that was too cheap to pass up ... back when Canada Post didn’t force you to take out a bank loan to pay for shipping.Steve McDonaldhttps://www.blogger.com/profile/06229640265009249231noreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-22049511632624561422020-02-11T15:04:33.594-08:002020-02-11T15:04:33.594-08:00This brings back memories. RadShack once had a sto...This brings back memories. RadShack once had a store in the Shelbourne St. K-Mart plaza. About 1972-3 I bought a loopstick coil to make a simple radio. It looked very much like the coil in your blog. RS sold a germanium transistor and a miniature film 365 uuF variable to go with it.<br /><br />I wired the parts on pressed wood pegboard, and found my receiver had no selectivity. Every station in Victoria was received. Not sure what I had done wrong - no doubt many mistakes. I don't recall what antenna I was using, maybe a 30 foot random wire. The ground was the copperclad rod sold by RS that I used with my Globe Patrol superregen RX.<br /><br />The only remnants I've saved from the project are some 9V battery snaps in a drawer. However the UBC club's inherited radio junkbox may have some loopsticks of the same or similar type.<br /><br />I also have a National dial exactly like yours saved away from early Hamsoc times. Wondering now if it came from the same source as yours... the Point Grey radio station, which donated much junk to Hamsoc, or maybe it was Satellite Electronics.<br /><br />Dan VE7DES<br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-62833703136235483282020-02-10T14:50:00.674-08:002020-02-10T14:50:00.674-08:00Love seeing this sort of ingenuity when materials ...Love seeing this sort of ingenuity when materials and parts from decades ago are next to impossible to find.<br />BTW, I used a slug-tuned crystal set and a long wire antenna when I was a HS student in Burns Lake eons ago. It was the only way to listen to rock n roll-- KOL and CKWX, as I recall--in a place with only a CBC repeater station.<br />Anonymousnoreply@blogger.com