https://www.ebay.com/itm/327233832168 and https://www.ebay.com/itm/327233831357?

The Realty Radio 1650 Model span from 1982-1984 (maybe 1985) but there were no less than 4 different -um models, maybe even more, they had additional features, every style looked different but they were all "Model 1650", these in the auction are probably 1983 and/or 84.  I find these extremely interesting from an historical perspective and what's most interesting here is the original documentations, particularly the distribution information book. This was from long after Herrick had divesested his company, but the distributions continued

[Img scr:https://i.ebayimg.com/images/g/Vp4AAeSwtcVqPqUV/s-l1200.webp

https://i.ebayimg.com/images/g/ZwIAAeSwrOpqPqUW/s-l1200.webp

Transcribed from the image:

July 13, 1987
Ms. Susan Romine PO Box 37 Fairmount, IL 61841

Dear Ms. Romine:
I would like thank you for your previous inquiry about Radio Realty. Our firm has been very fortunate in the number of individuals that have decided Radio Realty was an excellent opportunity for them. However, many potential Licensees think the territories were just physically too large. We certainly appreciated the input and because of this, have decided to reduce the size of each territory. By doing this, each Licensee will be able to concentrate their efforts on a more localized basis.
The licensing fee has been adjusted accordingly. The fee per territory is $2,500. Besides the exclusive territory you will also receive the following:

(1) Model 1650 Transmitter and/or

(1)Model 2000 Transmitter with Solid State Voice Storage (digital recording) no tape $300

(1) Cassette Tape Player-use with
(13-Minute Endless Loop Tape
(16-Minute Endless Loop Tape
(1) Demonstration Tape of Actual Messages
(1)Radio Realty Yard Sign
(250) Radio Realty Brochures
(500 Radio Realty Door Hangers

On the following page you can see how the territories for the State of Illinois are divided. If you have further interest, please call me at your carliest convenience.

Best regards,
Mark F. Kerr Marketing Director
MFK/evd Enclosure
A Division of The Marcus Gerard Corporation
4705 SOMERS AVENUE SUITE 1004 NORTH LITTLE ROCK, ARKANSAS 72116
501-753-8636 NATIONAL WATS 800-257-2346

3

AM Transmitter Bluetooth, USB, FM SD Player Stream to Your Vintage Tube Radio https://www.ebay.com/itm/127897973525?

Combination AM transmitter with built in player that accepts bluetooth, USB, and Micro SD Media as well as an FM tuner.

This is great for those that live in rural areas without AM reception or for transmitting period correct music/programs to your antique vintage radio.

Transmit your favorite music, radio shows, playlists, or other audio to your old antique tube radio through this AM radio transmitter!

No modifications or alterations need to be done to your vintage radio.

Includes the following operating modes:

Bluetooth - Pair your audio device with the built in Bluetooth receiver on the AM Transmitter

FM radio - Select the FM feature on the player and extend the White FM antenna wire

MicroSD - Put your favorite music/audio on your Micro SD card (up to 32GB) and insert card in the memory slot.

USB - Put your favorite music/audio on your USB stick and insert in USB port on front.

Place transmitter near your radio, extend the yellow antenna wire and transmit to your radio on 1000 kHz on the dial.

The transmitter is powered with your standard USB-C phone charger & cable (not included).

Note: Many USB-C phone chargers are noisy and create interference. a separate black ground wire with alligator clip is provided to connect to a ground terminal or radio chassis to eliminate interference.

Easy to use with included instructions.

1. Dual decoding supports music in MP3/WMA/WAV
2. Function: Bluetooth 5.0+lossless decoding+call+radio FM+AUX+USB+TF card
3. Support external audio source input LINE IN
4. Support radio FM, search frequency band (87.5MHZ-108.0MHZ)
5. Bluetooth transmission distance: within 20 meters
6. Buttons: three-button control, VOL-/AUTO/VOL+

$250

Description:

This listing is for a Ramsey AM25 AM transmitter, power supply, and antenna that has been upgraded, tested, and works to professional standards. If you're seeing this listing then you're probably already familiar with the AM 25 and Part 15 transmitters. If not, an online search should provide a manual (eBay doesn't allow links in listings).

However, *THIS* AM 25 is like no other:

* The power can be adjusted to meet F.C.C. Part 15 rules (meaning it can actually be legal to use).

* The transmitter can modulate past +125% without distortion (see video). This is a BIG issue with stock AM 25 transmitters.

* Modulation is linear from -100% to +125%.

* The frequency can be set to meet F.C.C. standards for the AM broadcast band (+/- 20Hz).

I'm surprised that all of the Ramsey AM 25 transmitters I've worked on needed modifications to make them usable, meaning sounding loud and clear. The instructions are vague and make suggestions that will result in poor performance. That said, the buyer of this AM 25 can expect these issues to have been resolved.

The transmitter operates on 10kHz channel spacing such is used in North and South America and is most efficient on frequencies above 1350 kHz. It's currently set to 1620 Khz in the expanded band but can be set to your favorite frequency if requested.

The video shows the modulation performance and the pic with the frequency counter shows that the carrier frequency can actually be set exactly. Sorry, neither the Sencor frequency counter nor the Belar modulation monitor are included (I need to write that as I've been asked before). What you DO get:

1) The upgraded Ramsey AM 25 transmitter shown in this listing and video

2) The 12V power supply

3) A wire antenna with RCA/Phono plug

Regarding an antenna, the transmitter will work fine with the included antenna, but those interested in better performance may want to build an outdoor antenna. Again, it's all online if you look. The buyer is responsible for proper operation of this transmitter. It will be set to your desired operating frequency and shipped after thorough testing. Despite what the instructions say, -DO NOT- adjust the bias control. Doing so made the stock AM 25 sound like garbage, and on this one, it is set for optimal performance. 

Have questions? Let me know...

Some freebie tech tips for those who already own an unmodified AM 25 (feel free to copy and distribute):

https://cybertekzine1990.substack.com/p/fm-in-liminal-space

"..... This isn’t Collinsville’s first rodeo with radio. About 15 or so years ago, a gentleman used to set up a hobbyist Part 15 station on 1620 KHz. AM in the parking lot of the canoe rental place on the weekends. It was a sporadic operation that despite its excellent engineering was still limited in range by the restrictions placed on it by license-free operation....."

I knew what he was talking about and just had to dig it up again. I've always found this Part 15 AM pickup truck station interesting. The Herald Courant did a story on it back in 2007 ( https//www.courant.com/2007/01/25/radio-collinsville/ ) it's a fun read, and the Hartford Radio History website used to feature a pictorial story on it but apparently took it down at some point, but it is still available on the Internet Archive: RADIO COLLINSVILLE https://web.archive.org/web/20111007212832/https://hartfordradiohistory.com/Radio_Collinsville.html

I'm wondering two things, one, what kind of transmitter is that? A homebuilt unit I'm guessing but what I find peculiar is that there's no cover on it, it looks exposed. The guy that took the pictures said he didn't see the owner of the truck around, so it's not like they took the cover off for the photo shoot or something. He also had an interesting grounding system that I've found peculiar. I wonder what of ever became of that part 15 pickup station. I recall something about another part 15 station in a van.. can't seem to recall where that one was right now.

This took place in California 1998, I never did know who this guy was that drove around taking field strength readings of all these Billboards, but at the time the part 15 AM billboards were big business around the country. The guy that started it (I forget his name at the moment) began by being a re-seller of talking house units to restaurants and gas stations etc. and eventually decided to manufacture a new part 15 AM transmitter himself with better audio quality, amongst his first customers was Atlantic Records, which had gone on to launch a whole slew of Atlantic Record Part 15 ventures over the next 5 or 6 years. But the primary use was for Billboard Radio, and that guy went from being a seller and leaser of Talking Houses to becoming a multi-million air leasing part 15 AM billboards across the entire country.

Anyway, those billboards seemed to have kind of pissed off this ham operator who got in his car driving to all the billboards in his area taking readings of those signals. I just thought it interesting to look back..

"Id like to relate some information about a local low power station in the Stockton,Ca area. This low power station is run by a car dealer! It's a low power am transmitter in a box with a 10 foot whip antenna high atop a billboard sign along the local freeway (hi-way 99) the station runs on AM 1610Khz. It's a low power am transmitter in a box with a 10 foot whip antenna high atop a billboard sign along the local freeway, the station runs on AM 1610 Khz and covers up and down the road about 3 to 10 miles! (This is no 100 MW transmitter, more like 2 or 5 watts) the 95 saturn stock radio picks it up all the way across town.

About a mile from the transmitter billboard is a 2'nd billboard that tells you to tune into 1610 AM for road info! When you tune into 1610 there is no road info from caltrans, no Local Wx, only a 10 minute endless loop tape playing advertisements for a local car lot. Over and over the broadcast tells you to "pull off the highway at the next exit
and drive into the car lot. (Much like 25% of the programming on on our local AMFM stations car spots, YUCK!!!)

The FCC was made aware of this commercial pirate station operating on the traveler information frequency of (1610 AM), the FCC tried to take RF readings and apparently decided that this station is legit!
It's obvious that if you have $2000 a month to spend on billboard space with
'3M' says it's okay to broadcast your commercial message, But if your trying to
run a community orientated low power station without corporate backing the FCC will run you off the band.

I have documented this bill board station on my web page 'Transmitter sites from hell ...' @ ... http://www.netfeed.com/~jhill
the billboard station pics are on the sub-page...http://www.netfeed.com/~jhill/1610.htm

Please add a LINK to this page , low power broadcasters need to know about this loophole !
Maybe some one can use this loophole to run a community orientated low power station ?

Put it in black and white .... DRAFT !!!!
this is a log of FIM reading taken on this billboard station by a real Radio Engineer
Signal Reading from a few miles north of site to 12.7 miles south of site.. (yes 12 freaking miles, that more then most LPFM's could hope for) all readings are on 10-14-1998 with real F.I.M.

11:24am hwy 26 and hwy-99 110 uv (micro-volts) = .011 mili volts.

11:45am Netherton Rd. & 99 190 uv

11:50am 3100 Carpenter Rd. & 3600 Hiway 99 S. Frountage Rd. This is near the very large TUNE TO 1610 AM billboard showing .35 milavolt / 350 microvolts.....

11:57am Boeing Rd. & S. hiway 99 .3 Miles North of Transmitter... 1.75 milivolts/meter 1750 microVolts (lots of audio)...

12:01 pm At the 1610 AM Pirate transmitter Billboard next to 'The Bedroom' store at Arch Rd. & hiway 99!! 2 VOLTS/METER!!!! (thats alot!)

12:05pm one half mile south of Transmitter 1.1 mv (milavolt), this level of about 1 Milavolt is like that of a clear channel AM station at night. Most car radio's can pick up a station at this signal level and bring it to volume with out static or noise (except for powerlines)

12:03pm One Mile South of Pirate transmitter Billboard 610 uv (microvolt) = 0.61 miliVolt... 1/2 a milivolt is a week night time signal from a clear channel AM station such as KFI 640Kc from say 700 miles out.

12:12pm 1.5 Miles South @ Stockton Airport runway & Hiway99 390 uv micro..

12:15pm 2 Miles South/Onramp to 99South .. 290 uv microvolts

12:28pm 8.2 miles south @ Tradeway Car Lot 35 uv MicroVolt....

12:33pm 12.7 Miles South @ Jacktone Rd. & Hwy99 2.5 uv Microvolt.. ..very week
After the heavy rain on 10-24-98 I could then hear (thats receive only) this 1610 pirate at my home (Salida,Ca.) on my
kenwood ham radio.! Thats like 15 miles or more, twice the range of a LPFM !

yep ;)
Side note, the voice of this station lives in Turlock , and is getting a LPFM for church

That's why I purchased a used Rangemaster, which blew those away.  Unfortunately, when I realized that it was not legal to operate in Canada (hey, I was still relatively new to this), I shut it down and sold it.

The ProCaster I got from Mark definitely rivals that Rangemaster (from what I can remember, anyway).  Great sound, even without the internal audio processing, not sure about the range, being in an apartment and in a built up area with lots of concrete, but it's really for my own use anyway (being RSS-210 certified, as opposed to BETS-1).

I'm not sure if it's because it is a V2, or I just got a good one (through Mark).  I'm impressed.

.

I know that that will horrify audio purists.  There are lots of audiophiles out there that swear by stereo as a listening experience.  Although I bet that most people, particularly those on a computer or in a car or on a cell phone, effectively listen to a single speaker in mono.

There are lots of people that still encode mp3's in 320kbps (the maximum) and even higher with other codecs, or flac (lossless).  Even when 128kbps is almost transparent to the source (depending on the source, of course).

But when you're dealing with transmitters that have an effective range of much less than a mile, probably feet for clear, static free audio, what's the point?  Even if you're the only listener, you're probably going to be listening in when there's static and other artifacts introduced to the sound just by virtue of the micro power used in these transmitters.

Broadcasting in mono FM will give these flea powered transmitters a bit more range, and more importantly, a bit more range for that static/artifact free listening zone.  There's more power for the content carrying signal (as opposed to the pilot and the stereo differences).

I would also bet that most people on most listening devices would not be able to tell the difference between 64kbps mono streaming and a much higher bitrate.  Even with headphones.

What you will be able to tell, even at 64kbps mono, is the differences in quality of the source material.  If the source material comes from noise-ridden 78s, and is in mono anyway (never mind maybe coming from acoustic recordings), then a higher bitrate will make no difference at all for anyone.  And stereo is just distortion, in my opinion - it's not the original intent.

I've encoded high quality modern stereo recordings at 64kbps mp3 mono, and then higher bitrates, again at mono.  It's very very difficult to discern the differences.  I'm sure you could come up with some material where it does make a difference, perhaps classical pieces with lots of instruments and background activity, but for common, popular music?  I doubt it.

While reading this article all I could think was "carrier current", which of course is what it is, but I mean AM or FM cc.. So if he's able to rig up an effective carrier-current high speed internet throughout his house via the telephone wiring then why couldn't the same be achieved with radio? I keep seeing post where people are looking for AM carrier-current components and not finding it. It's not something I'm particularly interested in myself but I've always wondered what the big complication was, are the AM carrier current gear really so difficult to DIY?

Would something like what this guy did be applicable to AM/FM somehow?

Here's some excerpts from the article:

Clever Brit successfully repurposes telephone wiring for gigabit internet throughout his vintage home
https://www.tomshardware.com/networking/clever-brit-successfully-repurposes-telephone-wiring-for-gigabit-internet-throughout-his-vintage-home-lad-converts-incomprehensible-mess-of-wires-into-high-speed-ethernet-links

A diligent British citizen has successfully converted his archaic telephone wiring into high-speed networking that gives him gigabit speeds basically anywhere in his house. ... ..  .. switching to telephone cables is a major upgrade since both ethernet and land-line use copper cabling as the medium. In this instance, it was Cat5 spread across the place. .... ... Moreover, British households, including this one, have daisy-chained telephone lines, which means a single central point branching off into several sockets, whereas ethernet requires a star topology where every end needs to be directly connected to the mains. Therefore, you need a powerful device that does the conversion, so a modem, while maintaining the signal properly, is the special part. Our guy chose the GIGA Copper G4201TM which uses G.hn modulation to break the signal into lots of tiny sub-carriers spread across a wide frequency band. Then, it basically plays a game of tug of war, balancing bit-loading in real time with robust error correction.  ..... ...
He also describes the dire state of his telephone wiring, arranged incompetently by an "idiot" that basically necessitated the use of this method. "The gigacopper device to do gigabit Ethernet over phone line is a miracle," he wrote while ending his blog with an open-ended suggestion to companies to tap into this lucrative market.

https://www.tomshardware.com/networking/clever-brit-successfully-repurposes-telephone-wiring-for-gigabit-internet-throughout-his-vintage-home-lad-converts-incomprehensible-mess-of-wires-into-high-speed-ethernet-links