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#1
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Content-Transfer-Encoding: 7bit Lines: 15 Message-ID: JAild.83554$E93.76920@clgrps12 Date: Sat, 13 Nov 2004 07:20:09 GMT NNTP-Posting-Host: 142.59.63.227 X-Trace: clgrps12 1100330409 142.59.63.227 (Sat, 13 Nov 2004 00:20:09 MST) NNTP-Posting-Date: Sat, 13 Nov 2004 00:20:09 MST Xref: number1.nntp.dca.giganews.com rec.radio.shortwave:404858 Is the Superheterodyne set over rated? It seems to me there were certain advantages to the OLD ways. Ease of control perhaps not being one of them. What was the WORST feature of the Regenerative sets? The BEST feature? Would it be worthwhile to build a kit? mike |
#2
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On Sat, 13 Nov 2004 07:20:09 GMT, m II
wrote: Is the Superheterodyne set over rated? It seems to me there were certain advantages to the OLD ways. Ease of control perhaps not being one of them. Actually, superheterodyne is a pretty "OLD" way. It's just that it has not been surpassed - till now, with the SDR - Software-Defined Radio (of which superheterodyne is the front end anyway). What was the WORST feature of the Regenerative sets? Selectivity, dynamic range, tricky adjustment. The BEST feature? Simplicity, cost. Would it be worthwhile to build a kit? It is *always* worthwhile to tinker with radios... ;-) Mike |
#4
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![]() "m II" wrote in message news:JAild.83554$E93.76920@clgrps12... Is the Superheterodyne set over rated? It seems to me there were certain advantages to the OLD ways. Ease of control perhaps not being one of them. What was the WORST feature of the Regenerative sets? The BEST feature? Would it be worthwhile to build a kit? mike I built a single compactron tube ( 3 tubes in 1 envelope) regen several years back: http://parelectronics.com/pics/regen2.jpg Lots of fun to listen to casually, but one quickly tires of the poor selectivity and fiddling. Dale W4OP |
#5
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![]() m II ) writes: Is the Superheterodyne set over rated? It seems to me there were certain advantages to the OLD ways. Ease of control perhaps not being one of them. What was the WORST feature of the Regenerative sets? The BEST feature? Would it be worthwhile to build a kit? You have to remember that Howard Armstrong, who "invented" the regen (he was issued the patent, but it's something you really just trip over rather than invent). then went on to invent the superheterodyne, which does seem to have come from deliberate effort. He was disatisfied with the regen, which led him to experiment and explore until he came up with the superhet. The regen is simple, and that's a big advantage. It provided good gain for a single stage, and it provides better selectivity than a single tuned circuit without regeneration. Beyond that, it's limited. It won't provide great selectivity, it is finicky, and can receiver limited types of modulation. No, it can't be a serious contender for the superhet. On the other hand, there is certainly an appeal to building something, and a regen does make it easier. One can even argue that if someone is going to build a simple receiver, a regen makes more sense; not only simpler, but suffering from none of the superhet's disadvantages when done simply. Some of the disadvantages, apart from the lack of good selectivbity, can be overcome at the cost of more complexity. Add an an amplifier stage before the detector, to isolate it from the effects of the antenna (which can cause the regen to go in and out of regen when you don't want it), add some voltage regulation, add an audio filter. Make sure theregen control is smooth. Charles Kitchin has done a fair amount of work on regens in recent years. Some of the circuits are floating around the web, and he's had quite a few articles in QST. I'm too lazy to dig up the biography once again. There have been a few other "improve the regen" articles in QST in the past decade, though I can't remember dates or author. The first used an optoisolator to add some isolation, and there was another using a bridge for isolation. Michael |
#6
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#7
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#8
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![]() Michael Black wrote: David ) writes: Edwin, not Howard. No, that's not an error, it's Edwin Howard Armstrong, and I've come across instances to suggest that he prefered to be called Howard. That certainly makes sense as author Tom Lewis in the book "Empire of the Air, The Men Who made Radio" generally refers to him as 'Howard Armstrong'. dxAce Michigan USA |
#9
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![]() "Michael Black" wrote in message ... m II ) writes: Is the Superheterodyne set over rated? It seems to me there were certain advantages to the OLD ways. Ease of control perhaps not being one of them. What was the WORST feature of the Regenerative sets? The BEST feature? Would it be worthwhile to build a kit? You have to remember that Howard Armstrong, who "invented" the regen (he was issued the patent, but it's something you really just trip over rather than invent). then went on to invent the superheterodyne, which does seem to have come from deliberate effort. He was disatisfied with the regen, which led him to experiment and explore until he came up with the superhet. The regen is simple, and that's a big advantage. It provided good gain for a single stage, and it provides better selectivity than a single tuned circuit without regeneration. Beyond that, it's limited. It won't provide great selectivity, it is finicky, and can receiver limited types of modulation. No, it can't be a serious contender for the superhet. On the other hand, there is certainly an appeal to building something, and a regen does make it easier. One can even argue that if someone is going to build a simple receiver, a regen makes more sense; not only simpler, but suffering from none of the superhet's disadvantages when done simply. Some of the disadvantages, apart from the lack of good selectivbity, can be overcome at the cost of more complexity. Add an an amplifier stage before the detector, to isolate it from the effects of the antenna (which can cause the regen to go in and out of regen when you don't want it), add some voltage regulation, add an audio filter. Make sure theregen control is smooth. Charles Kitchin has done a fair amount of work on regens in recent years. Some of the circuits are floating around the web, and he's had quite a few articles in QST. I'm too lazy to dig up the biography once again. There have been a few other "improve the regen" articles in QST in the past decade, though I can't remember dates or author. The first used an optoisolator to add some isolation, and there was another using a bridge for isolation. Michael |
#10
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![]() "Michael Black" wrote in message ... You have to remember that Howard Armstrong, who "invented" the regen (he was issued the patent, but it's something you really just trip over rather than invent). then went on to invent the superheterodyne, which does seem to have come from deliberate effort. He was disatisfied with the regen, which led him to experiment and explore until he came up with the superhet. [snip] The local oscillator operates on the regenerative principle, so Armstrong was obviously in a good position to develop the superhet. Fessenden had discovered heterodyning years before, but he was using Poulsen arc generators as oscillators. Frank Dresser |
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