Americana "last gasp" AM only transistor radio
 

My flea market friend gave me this still in the box Americana Chinese made AM only battery operated radio model 602. It runs on a standard 9V battery and it works; but, is not the best performing radio on the block.

This is not something that I would have bought; but, it was free and it appears to be one of the last AM only radios; so, I'll find a place for it.

Does anyone have any idea as to when these were made? I was thinking late '80's-early '90's; but, I really don't know.

http://i538.photobucket.com/albums/f...ricana0001.jpg

I remember seeing one of those back in high school - I think a friend's mother was trying to give it away - she had won it at bingo or something. So that would date it to late 80's or so. Also, I don't think I've ever seen anything made in Red China prior to the mid/late 80's.

And, I forgot to mention that this thing is so cheap that it does not even have an earphone jack. I was playing around with it tonight and it does not do too well on distant stations, even at night. It does OK on strong local stations; but, is pretty much useless otherwise.

Ain't gonna win no Beauty Prizes, neither...

If this radio plays well only on strong local stations and doesn't pull in distant ones, even after sundown local time, I'd say it probably has a bare-bones chassis with no more than four transistors; that or else, if it has six transistors or more, it may be far out of alignment. Another possibility is the battery is weak or nearly dead. I'd try the radio with a new battery before doing anything drastic. I have several battery-powered transistor radios here that won't work worth a darn if the batteries are the least bit low; since I am 33 miles east of Cleveland and the radio and TV station towers are about 10 or 15 miles further to the southwest, I notice it when any of my sets' sensitivity drops. When the batteries are good, I can get every Cleveland station here as well as if I were still in the suburbs; however, let the batteries go down to, for example, three volts for a 6-volt set and I lose just about everything but a 1-kW local station five miles away.

OTOH, your little portable radio may have been designed purposely with low sensitivity, for use in near-suburban or urban strong-signal areas. It sounds to me like this radio may have been a promotional item given away by radio stations during live-remote broadcasts.

It's funny, but I would rather expect this radio to contain a few dozen transistors,
but all inside the same integrated circuit. Any way the innards can be photographed?

I saw at least a half dozen of these on eBay last night, in white and beige. It may have been the last "table style" AM radio, only meaning it's not a pocket transistor set. I know Radio Shack kept that AM "Flavoradio" around long enough to be manufactured in China in the early 2000's.

Had one of those Flavoradios in the mid seventies. That was a honest
radio that could pull some DX at night.

I thought it would be one of those one IC deals. They had those AM broadcast band all in one ICs that they would build in electronics classes/schools. We need a picture of the inside please.

On the sensitivity issue its most likely antenna. If it has one of those tiny ferrite rod deals that the issue. The better the radio the better the antenna.

Hook a long wire up to it and watch it go.

If it's like an el-cheapo that I found awhile back, it's probably based on the MK484 IC (looks like a transistor, but it isn't)

I did open it and it has seven transistors. Of course, one (or more) of those may be wired as a diode as I really didn't pay that much attention. The loopstick antenna is small. It's really nothing more than a pocket radio chassis in a slightly larger cabinet. I'll post a picture of the inside as soon as I can.

I have a belt-clip stereo FM scan radio that uses the headphone cord as an antenna, and it works fairly well in this area which is about 35-40 miles from the Cleveland FM stations (which do not transmit from the city, but are scattered around at least two southwestern suburbs; I'm near Lake Erie, some 30+ miles from downtown).

FM, and particularly stereo FM, are much more demanding when it comes to signal strength than AM ever was, so I'm really amazed that my little "Sonaki" stereo FM belt-clip receiver works as well as it does in this area with such a poor antenna. I haven't found a way, however, to hitch an external FM antenna to this radio (no external terminals that I can see); if I could, I'll bet I could get stations 70 miles away very easily, although they might well be crowded together if the radio had an actual tuning dial (it doesn't).

As to AM, I did not realize that the size of the ferrite loopstick antennas in portable radios mattered that much; after all, the loopsticks in 6-transistor portables aren't much longer than maybe four inches, if that much, and they seem to do a creditable job of picking up usable local signals in daytime, as well as DX at night (whatever the true definition of "AM DX" is in these days of the FCC's 750-mile nighttime coverage limits for former clear-channel AM stations). They can't be too long in the shirt-pocket portables because of the small size of the cabinets, but in most of them they extend almost the width of the latter. The only radios I've seen that can use really long loopsticks are full-size portables; the AM loopstick in my Sony TFM-7200W AM/FM 3-volt portable, for example, must be at least six inches long and maybe longer, as the radio is a good-sized portable from the early 1970s.

I had an "America" just like the one pictured, but in a fit of cleaning/throwing out one day, I gave it to Goodwill :-(
I had no idea it was collectible, or one of the last AM-only transistors. Guess everything is collectible-to someone.
I have a tiny "National" AM-only mini-transistor, made in China, looks like it could have been made in the 90s. Length and width are about the same as a credit card; width maybe 1/4 in. I used to listen to Seattle Mariners games on it last summer or the year before, until it finally died. I still have it, in a box with other small transistor sets.

Sorry, meant to say "thickness" 1/4 inch.

Well their quality degraded severely by 1990 when I bought two of them. I think Mother still has one of them in case of power loss. It's good enough to pick up strong local stations but they are el cheapo extreme. Also the tuning caps on mine were very stiff and hard to fine tune.

Next time (if there is a next time) I see an "old" (70's) Flavoradio I'll pick it up and give it a shot.

I have the Tooob era equivalents of these Bad Boiz-a couple of pre-war Arvin sets-One has 2 tubes, & the other one has 3. They were salesmen's or travelers' sets, designed to be thrown in a suitcase, & they do a reasonable job of picking up the local Angel Modulation station in whatever town you found yrself in. They were both under $12, I think, new, so even back then if they got "borrowed" or lost it wasn't a big deal. The mighty 2-tube special, I think, ALMOST picked up WLAC, 1510 in Nashville one night...

FM is transmitted horizontally polarized like TV, so your antenna should be 'flat'. Generally with low power FM stations they use yagis so they can direct the signal exactly where they want it to go.

With am the big stations use 2 or 3 vertical antennas and can direct exactly where they want the main radiated lobe to go by phasing the antennas. Sense it skips all over the place, polarization doesnt matter. The general rule is bigger is better. All the ferrite rod does is makes the coil appear much larger than it really is.

Im not saying that that the front end and IF doesnt affect it, but antenna is the majority.

I have noticed some degradation with KNX, our local CA powerhouse that any radio, even you teeth could pick up at night through CA, NV, AZ on and on. I figured they just cut their power back trying to save money because of the economy.

...

Many full power FM stations now use circular polarization, in an attempt to provide a better signal to automobile radios and table radios that use "line cord" antennas, so orientation of the line cord or headphone cord in this case, may not be as critical as it once was.

According to the FCC website, KNX still transmits at 50KW.

http://www.fcc.gov/fcc-bin/amq?list=0&facid=9616

Perhaps their ground system has degraded over the years?

jr

I had an RS "Flavoradio" (in a sky-blue cabinet) for years as well, but unfortunately it got lost when I moved here 10.5 years ago. Don't know what happened to it. Probably got pitched with a bunch of other stuff being thrown out of the house (I wasn't there when the house I grew up in was being cleaned out in preparation for sale; long story and OT for this thread).

I don't know how often the Atlanta area or the New Orleans area (wherever your mother lives today) has power outages, but she will be ready for the next one, if and when...maybe. I say "maybe" because I wonder just how much emergency info she will hear over the radio. Wasn't there a discussion here just before the DTV transition addressing the fact that radio is utterly useless these days in emergencies, because radio stations no longer broadcast local emergency information--despite the fact that they must have EAS (Emergency Alert System) monitoring gear? :scratch2: I would think your mother's Flavoradio would be worse than useless :no: in any emergency worse than a power outage these days for that reason.

I had an Arvin model 540T 5-tube BC-only radio from at least the 1950s in a green metal cabinet (a shock hazard waiting to happen :eek:) I got from my aunt and uncle in the late '60s-early seventies when they were cleaning up their house. It had an external wire antenna and worked reasonably well in my area (at the time), east suburban Cleveland; however, I wouldn't have trusted whatever insulation there was between the chassis and the cabinet, as the grommets (if there were any) had probably disintegrated and were worse than useless as insulation material by the time I got the radio.

Where I live today, 33 miles from downtown Cleveland and ten-fifteen miles further from the city's radio stations, however, I don't know how well that Arvin set would have worked; for all I know it might have been a decent performer here, at least on the local station five miles from my apartment. It would definitely fail miserably trying to pick up a 0.5-kW day/0.042kW (42 watts, directional night pattern) station near where I grew up; that is, the radio might get the station during the day, but just barely. After sundown, forget it; the station's gnat-sighing-through-a-window-screen-at-ten-paces 42-watt night signal, along with the sharply directional nighttime antenna pattern, very neatly exclude my area, and everywhere else east of me, from their coverage--all night long, until the following morning (the station has a PSA, pre-sunrise authorization, to operate at reduced power if sunrise occurs before 6 a.m. local time, but I still wouldn't hear it here until well after dawn--and if I did hear it before then, it would be so weak as to be unlistenable).

These radios, as you mentioned, were built only for local AM reception; your 2- and 3-tube sets more so than mine was (I don't have mine anymore), but not by much.

Interesting, the antennas for KNX are located in a public park where all the local soccer teams meet. Its says the phase angle is 0 so I wonder if their just broadcasting omni.
Interesting stuff.

I appears that they are only using one tower, so it would be non directional (ND-1 is shown). If you check the "ASRNs within .5 km" list, it appears that there are 2 nearby towers that are owned by CBS, perhaps these were used at one time to provide a different pattern day- to -night.

jr

Update... Scott Fybush to the Rescue....He says that in the late 50s CBS experimented with a directional array...but it did not work out:

http://www.fybush.com/site-020313.html

This guy has got my KIWA BCB loop borrowed out...Maybe I oughta get it back from him, & hook it up to the little Arvins...Mbwahahahahaha...I took the KIWA over to a bud's house one time, Sunday afternoon in the winter, we hooked it up to his-I think it was a Philco late '30s cathdral-that he'd had trouble picking up ANYTHING on, & Voila' ! the radio came alive...We were picking up AM daytimers outta KY & Virginia, local service stations that whose coverage usually petered out by their county lines...Plus, he lives in a bowl/box shaped valley, closed in on 3 sides by mountains,& on the 4th side by one a field's length away. The nite Mr. 2-Tuber almost picked up WLAC, I had it hooked up to a reasonable antenna I have strung around the ceiling in my "Ship's Radio Room". I had Terry re-cap him not long ago, he may do better now. Not too shabby for a el-cheapo 72 yr old set...

I have two of those Flavoradios and you are right. They are a true example of a real transistor radio. The performance is typical of a six transistor set of the era. They are cheaply made but not flimsy and are quite dependable. Everyone should have at least one of these.

Well, I had picked up a second hand battery-operated weather radio with an alert for her about six months before she moved back home. It didn't have "SAME" but proved useful nonetheless - woke her up at least once for a tornado warning the next county over.

We have one AM station (WWL, which also simulcasts on FM) that is very dependable for news/weather coverage during the day, and although they've slipped a few times they've often covered weather events live in the wee hours. We used to have WDSU-TV 6 to fall back on - their audio signal was on the bottom of the FM dial.

Truthfully, I can count on my transistor and weather radios and the rotary dial phones when the power fails.

I do remember seeing one new AM-only radio about 2004 or maybe 2005. This was soon after a large chain of discount food stores (one of the ones that mainly sells their own brands) had been selling a "Micro FM" radio for $1, including earphones.
This one was built into the same tiny clear plastic cabinet the FM radios were, only it had a dial (not a scan button) for AM, and a tiny (2 cm long, maybe a gram) loopstick visible in the case.
It did not perform nearly as well as a Micro-FM, downright abysmal. It needed about 25mV/m to hear a thing, and was about 300 kHz off calibration.
I might still have it in the basement somewhere.

I made a YT video of this radio, showing the inside.

http://www.youtube.com/watch?v=L7x4lgmGTP8