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MOP CAP <email@domain.com>: Oct 11 08:44PM -0700 Does anyone have a recomendation for a quality AM receiver? I have a cabin in the low Sierras and have trouble receiving AM. I would prefer one that would not require an outside antenna. Thanks, CP

oldschool@tubes.com: Oct 11 10:54PM -0500 >one that would not require an outside antenna. >Thanks, >CP     I live in a rural area, but it sounds like your cabin is even more rural. No matter what kind of radio you get, you will not get many stations without an outdoor antenna. The good news, for AM, all you really need is a piece of wire strung outside. 20 or more feet of wire between a few sturdy trees works fine, then run it into the house by drilling a 1/4" hole and caulk around it once it's inside. Pretty much any sort of wire will work outdoors, insulated or bare. Use some insulators on the ends. I'd use insulated wire coming in thru the wall.   If your AM radio has no antenna connector, but has a telescoping antenna, just coil the wire around the telescoping ant numerous times. I do this in my barns, because they are metal buildings. Without the outdoor wire, I'd get no stations. That wire works for FM too, but not quite as good.   If you use trees, be sure to leave some slack in the wire. Trees sway in winds, and if the wire is tight, it may break.

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Oct 12 03:31PM +1100 On 12/10/2017 2:44 PM, MOP CAP wrote: > one that would not require an outside antenna. > Thanks, > CP   **Assuming you have no internet capability (the best way to receive AM), then your next best option is to find an old, 1960s vintage, solid state, car radio. Since few car radios had FM capability back then, the AM qualities were excellent. If you have lots of cash, then one of these will provide superb AM performance:   http://classichifi.info/SansuiTU-X1.shtml   I had one on the bench last year. Surprisingly impressive and quite sophisticated (even has a synchronised detector!) AM section. A bit much for a cabin radio though.   -- Trevor Wilson www.rageaudio.com.au

John-Del <ohger1s@gmail.com>: Oct 12 02:36AM -0700 On Thursday, October 12, 2017 at 12:31:43 AM UTC-4, Trevor Wilson wrote:   > -- > Trevor Wilson > www.rageaudio.com.au     I agree with the vintage part Trevor, but I'd go with a typical house radio. I have a bunch of early 60s AM transistor radios and many of them feature an RF amplifier. An Emerson 911 for instance picks up as good as any radio I've ever had, and they're pretty cheap if you catch one just right.   Also, a Select-A-Tenna supposedly works wonders for DXing although I've never tried one:   https://www.amazon.com/Select-A-Tenna-Regular-Model/dp/B0015A81HI

"J.B. Wood" <arl_123234@hotmail.com>: Oct 12 06:52AM -0400 On 10/11/2017 11:44 PM, MOP CAP wrote: > one that would not require an outside antenna. > Thanks, > CP   Hello, and you want a radio of requisite sensitivity so you can enjoy the "quality' of AM radio? Can you parse languages other than English? Just kidding. In addition to the advice already provided by others, you might want to check with a seller like C.C. Crane. I assumed by "AM" you meant the medium wave (535-1700 kHz) band. A multi-band "communications" type receiver (with an RF gain control) might be a solution but likely isn't the least expensive one if bought new. In any event, reception using a simple, old-fashioned long wire antenna will most often provide better performance than a built-in telescoping whip antenna. Another possibility is to use a passive (no batteries required) variable capacitor tuned loop antenna. These can be built or bought, can be used indoors, and I've seen them dramatically improve the MW band performance of inexpensive transistor portables. The radio is simply positioned at the base of the loop (radio's internal ferrite loop becomes inductively coupled to the antenna so no wire connection to the radio is required), the radio is tuned in the vicinity of the AM station of interest, and the loop capacitor is adjusted for maximum signal. Sometimes the radio needs to be slightly repositioned to optimize the radio-to-loop coupling. And finally you can rotate the radio and tuned loop together for the strongest reception. Please let us known what works for you. And one last thing: Don't rule out the use of FM (assuming you like whatever program content is being offered) as I've seen situations where AM reception is lousy but FM works. Sincerely,   -- J. B. Wood e-mail: arl_123234@hotmail.com

"pfjw@aol.com" <pfjw@aol.com>: Oct 12 04:32AM -0700 On Wednesday, October 11, 2017 at 11:44:10 PM UTC-4, MOP CAP wrote: > one that would not require an outside antenna. > Thanks, > CP   Mpffff... This is an easy one. If you are looking, primarily, for good reception over top-notch sound (mostly wasted on AM anyway), and this is to be a single-purpose device, look for something like a solid-state GE "Super Radio" or similar. They are fair-enough sounding and far better than average at AM DXing capabilities. Low in cost for very good results.   http://www.ebay.com/itm/VINTAGE-GE-SUPERADIO-SUPER-RADIO-LONG-RANGE-AM-FM-HI-PERFORMANCE-VERY-NICE-/401419473964?hash=item5d7677142c:g:e9AAAOSwbRJZvvX8 I keep one of these at our summer house that is no slouch at all. The AM band is pretty busy, especially at night.   A step up from there would be a multi-band radio such as a Zenith TransOceanic. Of those, the ne-plus-ultra would be the RD7000Y - and why that one? All silicon, has the tunable weather band, and will give you some amusing shortwave capacity.   https://www.ebay.com/dsc/i.html?_sacat=0&LH_TitleDesc=1&_udlo=&_udhi=&_ftrt=901&_ftrv=1&_sabdlo=&_sabdhi=&_samilow=&_samihi=&_sadis=15&_stpos=19027&_sop=12&_dmd=1&_ipg=200&_nkw=Zenith+RD7000Y&_ex_kw=&_in_kw=1 One of these has lived at my work desk for over 20 years.   Hard-Core would be a Communications Receiver, something in the Hallicrafters, Collins or National lines - which are a whole different can of worms, do want an outside antenna, and likely will contain tubes rather than transistors.   And, one of these will truly separate fly-poop from pepper. Give it an 80' longwire and you will be getting AM from Hawaii - or thereabouts.   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: Oct 12 06:09AM -0700 > And, one of these will truly separate fly-poop from pepper. Give it an 80' longwire and you will be getting AM from Hawaii - or thereabouts.   > Peter Wieck > Melrose Park, PA   The old Vega/Ocean radios are very cheap dx sets. Some mericans might not like their origins. But don't worry, they don't run Kaspersky.     NT

"pfjw@aol.com" <pfjw@aol.com>: Oct 12 07:03AM -0700 On Thursday, October 12, 2017 at 9:09:19 AM UTC-4, tabb...@gmail.com wrote:   The old Vega/Ocean radios are very cheap dx sets. Some mericans might not like their origins. But don't worry, they don't run Kaspersky.   I keep one of these as well - a small hand-held - and, yes, it does very well. Competitive, but not better than my Siemens RK747. They are not easy to find in good condition, nor do they wear well. I paid $2 + about 4 hours of very persnickety work fixing the battery compartment and re-securing the guts on mine. Pure blind luck that it worked at all - but it does, and well.   https://www.doctsf.com/grandlivre/fiche.php?ref=40940 (not mine).   But if we are going into Euro-Exotics, the very best consumer-grade DX radio I have in all bands is this one:   http://www.ebay.com/itm/Grundig-Satellit-700-World-Receiver-FM-SW-Radio-/162699281459?hash=item25e1a20433:g:QTUAAOSwls5Y6-Vk   The second best is the Zenith RD7000Y (and the best for sound overall). Followed by the Grundig YB500.   http://www.ebay.com/itm/GRUNDIG-YATCH-BOY-500-YB500-RADIO-IN-BOX-AND-PAPERWORK-/142532921023?hash=item212f9fc6bf:g:pqEAAOSwdKZZ2tbY   Point being that the smaller radios have smaller sound - if that is a consideration.   Repeat: Communications Receivers are a whole different thing. If the OP wants to pull stations from the moon or Mars, that should definitely be a consideration.

MOP CAP <email@domain.com>: Oct 12 07:42AM -0700 Thanks all. CP

makolber@yahoo.com: Oct 12 08:13AM -0700 On Thursday, October 12, 2017 at 10:42:32 AM UTC-4, MOP CAP wrote: > Thanks all. > CP   first depends what you mean by quality, able to hear weak stations? or high fidelity?   in either case, the big problem with AM is electrical interference which will sound like buzz noise usually.   if you are out in the woods, your own stuff will be the only source so you have a chance to control it   light dimmer, wall warts, fluorescent lights computers, all these are potential sources of electrical interference.   use a battery operated radio and turn off the electricity and you will be surprised what you can hear especially at night.       m

micky <NONONOmisc07@bigfoot.com>: Oct 12 12:04PM -0400 In sci.electronics.repair, on Thu, 12 Oct 2017 15:31:26 +1100, Trevor >AM qualities were excellent. If you have lots of cash, then one of these >will provide superb AM performance:   >http://classichifi.info/SansuiTU-X1.shtml   Quite a radio!   But as to the car radio, aren't they so good because of the metal body of the car that surrounds them? A ground plain? Or is that only for FM. I know for FM every car radio I had worked better than every table radio except 1, but I didn't have a chance to compare AM

"pfjw@aol.com" <pfjw@aol.com>: Oct 12 09:35AM -0700 On Thursday, October 12, 2017 at 12:04:43 PM UTC-4, micky wrote:     > >I had one on the bench last year. Surprisingly impressive and quite > >sophisticated (even has a synchronised detector!) AM section. A bit much > >for a cabin radio though.   OK - here is "the deal" about car radios. Keep a few things in mind:   a) Moving cars are noisy, very noisy. Noisier than any listening room in your house by a very large margin. b) Cars, in general, are tiny as compared to about any room in your house other than, perhaps, the bathroom. c) Cars move, by their very nature. So they are pretty much always in motion relative to the transmitter by both angle and distance.   So, car radio manufacturers worry very, very little about s/n ratios, stereo separation, muting capacity, stereo/mono switching or any of the niceties found on even a relatively simple home tuner. They DO focus on sensitivity and AFC, some even do AVC based on ambient noise within the car. And, the bandwidth of the typical car radio after filtering is pretty wretched in many cases.   Meaning: a car radio will *receive* acceptably (for a car) under conditions that would have a decent tuner on full mute - or if the mute is disabled, making so much noise as to be intolerable.   Of course, what with HD radio and the concurrent 'cliff effect' of HD listening, how this works is even more obvious.   Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: Oct 12 06:15AM -0700 > Seems like a pretty simple choice to me. I would prefer to keep my money for other things than wasting it needlessly on power.   > Peter Wieck > Melrose Park, PA   That seems confused. I was talking about the ballasts, which obviously do not need replacing. The tubes you refer to are hardly likely to be original, and even if they are replacing them won't save any power or money. All the OP needs is a 2 pole switch or relay.     NT

"pfjw@aol.com" <pfjw@aol.com>: Oct 12 07:14AM -0700 > That seems confused. I was talking about the ballasts, which obviously do not need replacing. The tubes you refer to are hardly likely to be original, and even if they are replacing them won't save any power or money. All the OP needs is a 2 pole switch or relay.   It is the ballasts that drive the consumables. Magnetic ballasts of that vintage cannot handle T8 or T5 lamps, some cannot even handle high-efficiency T12 lamps. They also require manual-start switch systems which further degrades the lamps. They also consume considerable power in their own right.   A "smart" electronic ballast will adapt to various lamp options, consumes 30% less power, and will very nearly triple the longevity of the lamps and halve the overall power consumption. As well as being adaptable to input power from 100 - 240 VAC.   The analogy I would use is that I am not required to use single-weight non-detergent oil, paper oil filters (if any at all) and non-resistor plugs in a vintage automobile. Nor am I required to use gutta-percha gaskets or leather belts - that is if I actually wish to drive it.   Peter Wieck Melrose Park, PA

Foxs Mercantile <jdangus@att.net>: Oct 11 10:26PM -0500 > wrote:   >> I shot on ranges from Texas to New England and points between.   > Words typed by an ANTI-AMERICAN who according to this sentence   Once again proving what a clueless fuckwit you are.     -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com

Foxs Mercantile <jdangus@att.net>: Oct 11 10:27PM -0500 > For the record, we have been to China - it is a fascinating country   I've been there twice on vacation. The most striking part of China, is that while we allow bridges full of traffic to fall into rivers, they are plowing tons of money into their infrastructure.     -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com

"pfjw@aol.com" <pfjw@aol.com>: Oct 12 05:57AM -0700 On Wednesday, October 11, 2017 at 11:27:34 PM UTC-4, Foxs Mercantile wrote: > The most striking part of China, is that while we allow > bridges full of traffic to fall into rivers, they are plowing > tons of money into their infrastructure.   Something similar happened after WW-II - the US infrastructure from rails to factories was almost entirely worm out due to heavy use. On the other hand, European and Japanese infrastructure was crushed. They built new from everything they had learned from the US (Deming), modern production methods and more. They revised their entire rail system ... and subsequently cleaned our collective and several clocks for efficiency. They did not have the materials and wealth to replace their transportation systems with automobiles, so they maintained their passenger and light-rail systems.   On the other hand, we built the Interstate and Defense Highway system from the 50s to the 80s, where it became the envy of the world. Now, a highway is designed to last about 25 years without much maintenance. A highway bridge somewhere to about 50 years, with the upper limits around 75 years. Guys and gals - we are there - and beyond.   Interstate and federal highways are paid for by the gasoline tax. Which has remained at $0.184/gallon since 1993. It should be $0.317/gallon by inflation Writing for myself, I would gladly pay that amount if I could be assure of safe bridges and highways, and better public transportation options - and that it would not be diverted for other purposes.   Peter Wieck Melrose Park, PA

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Oct 11 01:33PM -0400 On 10/11/2017 02:38 AM, micky wrote: > The antenna that came on my 2005 Toyota is about 16" long and the top > ten inches have a wire coiled around in it, like the snake on a > caduceus. Does this wire do anything or is it just to impress people?   You can use Ls and Cs to make "loaded" vertical antennas, i.e. ones that are resonant but much shorter than 1/4 wavelength, but in those the L goes on the bottom and the C on the top. Putting extra L on top doesn't make immediate sense electrically, so I expect it's for acoustics or pedestrian protection or something less obvious like that.     http://www.arrl.org/files/file/History/History%20of%20QST%20Volume%201%20-%20Technology/QS03-73-Sevick_opt.pdf   Cheers   Phil Hobbs

dplatt@coop.radagast.org (Dave Platt): Oct 11 12:41PM -0700 In article <39hstc55tv0do41luus8dki8d1beon5okv@4ax.com>, >this is my 8th convertible over 50 years and all the other ones had >standard antennas, usually in the front** but sometimes in the rear, and >I never heard any noise from them.   My fuzzy recollection is there's a bit of a tradeoff.   Without the helical spoiler, the antenna tends to generate a fairly uniform "wake vortex" - an alternating flow of air behind the antenna, which switches directions repeatedly. It'll tend to be "in sync" from the top of the antenna to the bottom. If the frequency at which the vortex is alternating happens to match the resonant frequency of the antenna, the antenna can vibrate - a bit like a reed in an oboe. So, at certain speeds, the antenna can buzz or hum.   The spoiler breaks up the airflow, making it more turbulent... and due to the helical winding it makes the turbulence different at each point up the antenna. As a result, you can get more "broadband" wind noise, overall, but the turbulence won't excite a physical resonance in the antenna anywhere near as well as a "regular" vortex would, and so the antenna doesn't sound off at specific driving speeds.

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