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Superadio II question
Just picked up a Super II for $10 today. The FM antenna is missing the last
segment and I'm curious if anyone has a suggestion as to a replacement. Even in its 'shorter' condition, I can still pick up a hard-to-get FM station. Does anyone have a RadioShack substitution idea? The Date Code is 6140C.....anyone know what it means....the 40th week of 1961? The serial number is 192590.....anyway of correlating that to a date? Any information you can provide will be appreciated. I've visited many Superadio websites but didn't find one that gave date codes. thanks elfa BTW....the sound is incredible! It beats all the rest of my portables by a mile. |
Attach a wire the length of the last segment. It might not be pretty, but
I'll bet it would work S. |
In article , Warpcore says...
Attach a wire the length of the last segment. It might not be pretty, but I'll bet it would work S. Actually....I have no idea how long the missing segment (or segments) are but I'm thinking that with 24 inches still there, that's probably enough for FM. Amazingly, I have yet to find a website that explains FM whip antennas and the best way to use them. I have a Zenith TransOceanic and its manual states that its combination SW/FM whip should be pulled out only 18 inches and angled at 45 degrees to the horizontal for best reception when using FM. Maybe what I've got left is enough and a whip any longer wouldn't make reception any better. elfa |
elfa wrote:
Actually....I have no idea how long the missing segment (or segments) are but I'm thinking that with 24 inches still there, that's probably enough for FM. Amazingly, I have yet to find a website that explains FM whip antennas and the best way to use them. A quarter-wave length on the FM band is about 30", +/- depending on the actual frequency. I'd aim for that. -Bill |
In article , --exray-- says...
elfa wrote: Actually....I have no idea how long the missing segment (or segments) are but I'm thinking that with 24 inches still there, that's probably enough for FM. Amazingly, I have yet to find a website that explains FM whip antennas and the best way to use them. A quarter-wave length on the FM band is about 30", +/- depending on the actual frequency. I'd aim for that. -Bill Thanks Bill....that's the first piece of information I've ever heard on FM whip antennas. elfa |
elfa wrote:
In article , --exray-- says... elfa wrote: Actually....I have no idea how long the missing segment (or segments) are but I'm thinking that with 24 inches still there, that's probably enough for FM. Amazingly, I have yet to find a website that explains FM whip antennas and the best way to use them. A quarter-wave length on the FM band is about 30", +/- depending on the actual frequency. I'd aim for that. -Bill Thanks Bill....that's the first piece of information I've ever heard on FM whip antennas. elfa Then maybe if I expound others will chime in with their info. Generally you can consider a FM whip as a quarter-wave vertical or 'ground plane' type antenna. You can go out and measure the one on your car to get a good idea of the consistency of this length. A quarter-wave vertical gives a low input impedance, theoretically around 30 ohms but in practice a bit higher. A key part of the quarter-wave vertical system is the ground plane. In a portable radio its not so easy to establish a good ground plane but thats not a big issue. Portable sets are typically most interested in local signals and you can adjust the whip around if the radiation angle or length ain't book spec. If you were doing the same for an outdoor fixed antenna you'd want to focus on the ground plane to obtain uniform low angle omni-directional coverage. FM broadcast stations these days tend to use circular polarization more often than not. That tends to minimize the differences between a horizontal receive antenna (like a dipole) and a vertical antenna (like a whip). Some old timers still transmit with one or the other, or a combination of the two, but circular tends to provide better coverage given that FM rcv antennas may range from a Walkman headphone cord to a new Lexus driving up a steep hill. I'm still a bit miffed about the TO instructions for 18"...maybe their input is high impedance and the 18" configuration would certainly send the impedance to the high end of the scale???. The classic formula for a quarter-wave vertical/whip is 264 divided by Megahertz, the result is in feet. 98 MHz would give 2.69 feet or 32.3 inches. The diameter etc have a bit of effect on the formula but its close enough for hacking around with. So there. Now you have some ammunition to play with. -Bill |
In article , --exray-- says...
elfa wrote: In article , --exray-- says... elfa wrote: Actually....I have no idea how long the missing segment (or segments) are but I'm thinking that with 24 inches still there, that's probably enough for FM. Amazingly, I have yet to find a website that explains FM whip antennas and the best way to use them. A quarter-wave length on the FM band is about 30", +/- depending on the actual frequency. I'd aim for that. -Bill Thanks Bill....that's the first piece of information I've ever heard on FM whip antennas. elfa Then maybe if I expound others will chime in with their info. Generally you can consider a FM whip as a quarter-wave vertical or 'ground plane' type antenna. You can go out and measure the one on your car to get a good idea of the consistency of this length. A quarter-wave vertical gives a low input impedance, theoretically around 30 ohms but in practice a bit higher. A key part of the quarter-wave vertical system is the ground plane. In a portable radio its not so easy to establish a good ground plane but thats not a big issue. Portable sets are typically most interested in local signals and you can adjust the whip around if the radiation angle or length ain't book spec. If you were doing the same for an outdoor fixed antenna you'd want to focus on the ground plane to obtain uniform low angle omni-directional coverage. FM broadcast stations these days tend to use circular polarization more often than not. That tends to minimize the differences between a horizontal receive antenna (like a dipole) and a vertical antenna (like a whip). Some old timers still transmit with one or the other, or a combination of the two, but circular tends to provide better coverage given that FM rcv antennas may range from a Walkman headphone cord to a new Lexus driving up a steep hill. I'm still a bit miffed about the TO instructions for 18"...maybe their input is high impedance and the 18" configuration would certainly send the impedance to the high end of the scale???. The classic formula for a quarter-wave vertical/whip is 264 divided by Megahertz, the result is in feet. 98 MHz would give 2.69 feet or 32.3 inches. The diameter etc have a bit of effect on the formula but its close enough for hacking around with. So there. Now you have some ammunition to play with. -Bill Thanks again....I'll copy and paste this to a document. Question....what about angling the antenna...ie, not vertical but maybe at a 45 degree angle. I mention this as my Zenith Oceanics manual recommends it. And the manual also says to only pull the antenna out about 16 inches. elfa |
elfa wrote:
Thanks again....I'll copy and paste this to a document. Question....what about angling the antenna...ie, not vertical but maybe at a 45 degree angle. I mention this as my Zenith Oceanics manual recommends it. And the manual also says to only pull the antenna out about 16 inches. elfa I'm gonna answer that with 'do whatever works'. VHF (FM) reception conditions can vary wildly from one side of the room to the other. When the TOs were made there was no circular polarization so that advice may have lost a bit of creedence over the years. Still dunno about the 16". I have a TO 3000-1 squirreled away, next time I find it and dust it off I'll try that. -BM |
Attach a wire the length of the last segment. It might not be pretty, but
I'll bet it would work . Maybe an aluminum knitting needle will work. It can fit down into the hollow whip. Bill, K5BY |
In article , WShoots1 says...
Attach a wire the length of the last segment. It might not be pretty, but I'll bet it would work . Maybe an aluminum knitting needle will work. It can fit down into the hollow whip. Bill, K5BY Tried it already with a short piece of whip antenna from my junk box. There's something inside the last extension that prevents it from going in very far. elfa |
For what it is worth, the SR II antenna is 37 inches long and has 7
sections. craig "elfa" wrote in message ... In article , WShoots1 says... Attach a wire the length of the last segment. It might not be pretty, but I'll bet it would work . Maybe an aluminum knitting needle will work. It can fit down into the hollow whip. Bill, K5BY Tried it already with a short piece of whip antenna from my junk box. There's something inside the last extension that prevents it from going in very far. elfa |
ELFA,
For 'very good' FM reception on a GE Superadio II use the FM Dipole Antenna Terminals on the back righ side of the radio. - - - Form the simple 300 Ohm Twin Lead FM Dipole Antenna's 'arms' in a "V or in a Half-Square |__. .__| to generally receive your best signal. For the 'best' FM reception on a GE Superadio II use an Multi-Element FM 'outside Omni or Yagi Antenna with 75 Ohm Coax Cable and a 75 300 Ohm Matching Transformer connected to the radio's FM Antenna Terminals on the back righ side of the radio. OBTW: The Whip Antenna on the GE Superadio II Measures 38.5 " Long. FWIW: Most of the new car 'solid' (one piece) antennas measure 39". iane ~ RHF .. .. = = = elfa = = = wrote in message ... In article , WShoots1 says... Attach a wire the length of the last segment. It might not be pretty, but I'll bet it would work . Maybe an aluminum knitting needle will work. It can fit down into the hollow whip. Bill, K5BY Tried it already with a short piece of whip antenna from my junk box. There's something inside the last extension that prevents it from going in very far. elfa |
You may want to invest in a "ribbon dipole" antenna,
probably about 3 bucks at your nearest discount store of choice. Said antenna will perform even better than a whip, especially if you've got the ability to mount it outside of the house. Radio Scrap (and others) also sell outdoor antennas which will work. At any rate, you've got one of the better FM receivers, and it should provide excellent service. 73, Steve Lawrence Burnsville, MN "elfa" wrote in message ... | In article , --exray-- says... | | elfa wrote: | | Actually....I have no idea how long the missing segment (or segments) are but | I'm thinking that with 24 inches still there, that's probably enough for FM. | | Amazingly, I have yet to find a website that explains FM whip antennas and the | best way to use them. | | A quarter-wave length on the FM band is about 30", +/- depending on the | actual frequency. I'd aim for that. | | -Bill | | | Thanks Bill....that's the first piece of information I've ever heard on FM whip | antennas. | | elfa | --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.516 / Virus Database: 313 - Release Date: 9/1/03 |
Thanks! Great help! That's what I'll look for.
elfa In article , craigm says... For what it is worth, the SR II antenna is 37 inches long and has 7 sections. craig "elfa" wrote in message ... In article , WShoots1 says... Attach a wire the length of the last segment. It might not be pretty, but I'll bet it would work . Maybe an aluminum knitting needle will work. It can fit down into the hollow whip. Bill, K5BY Tried it already with a short piece of whip antenna from my junk box. There's something inside the last extension that prevents it from going in very far. elfa |
In article . net, Stephen M.H.
Lawrence says... You may want to invest in a "ribbon dipole" antenna, probably about 3 bucks at your nearest discount store of choice. Said antenna will perform even better than a whip, especially if you've got the ability to mount it outside of the house. Radio Scrap (and others) also sell outdoor antennas which will work. At any rate, you've got one of the better FM receivers, and it should provide excellent service. 73, Steve Lawrence Burnsville, MN It outperforms my Sony 2010 on FM. There's really only 1 FM station I'm interested in and so far, the SRII picks it up better than the rest of my portable radios (exception being a regular RS desktop, A/C powered AM/FM radio). elfa "elfa" wrote in message ... | In article , --exray-- says... | | elfa wrote: | | Actually....I have no idea how long the missing segment (or segments) are but | I'm thinking that with 24 inches still there, that's probably enough for FM. | | Amazingly, I have yet to find a website that explains FM whip antennas and the | best way to use them. | | A quarter-wave length on the FM band is about 30", +/- depending on the | actual frequency. I'd aim for that. | | -Bill | | | Thanks Bill....that's the first piece of information I've ever heard on FM whip | antennas. | | elfa | --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.516 / Virus Database: 313 - Release Date: 9/1/03 |
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