I'm selling off my Part 15 AM equipment

[Black_Shire]

Hello All,

I have moved to an apartment building where I can no longer engage in Part 15 AM broadcasting, so I am thinning my equipment inventory. The following items all work and are in like-new condition. (If the web page URLs below won't open in this posting, you can copy-and-paste them onto your web browser's URL line and open them from there.)

Any interested persons can e-mail me at [email protected] . Payment by PayPal is preferred (my e-mail address is my PayPal address), but checks and money orders are acceptable as well. If payment is by check, the item or items will be shipped after the check clears. Here are the items:

4 Talking House FCC Certified Part 15 AM transmitters, $60 each plus $15 postage each
(Features and specifications listed at: www.talkinghouse.com and www.actradio.com )

1 Talking House external (outdoor) remote Antenna Tuning Unit (ATU), connects to transmitter using 25' or 125' of RG-6 TV coaxial cable (not included) and uses a 102" (8.5') CB whip antenna (not included), $12 plus $5 postage
(See ATU near the bottom of this page: http://www.actradio.com/schools/schools.htm )

1 TalkingSign FCC Certified Part 15 AM transmitter, $60 plus $10 postage
(Features and specifications listed at: http://www.chezradio.com/talkingsign.html )

Thank you for looking.


-- James Jason Wentworth

 

[radioboy]

Jason,

I don't need any items right now..but good to see you here! You were a great help when I was just starting out. And, I'm still on the air..and the internet.

 

[Black_Shire]

Hello Alan,

Thank you for your kind compliment. Haven't been on here for a while, and it's heartening to see the increased interest in community radio.

I'm keeping a couple of Part 15 AM transmitters to putter around with. I use one Talking House to hear the audio from the TV on a Walkman late at night (it works better than Part 15 FM here, with several FM stations' towers atop a nearby ridge) to avoid disturbing the other building residents.

The landlady would never allow a small hole through the wall to the balcony for the Talking House remote ATU's coax, and the balcony door is sealed too tightly (it *has* to be for the winter, here in interior Alaska!) to run even a special flat "under door" RG-6 coax below the door. I have a Radio Systems Phase II CCAM transmitter, so I may try a neutral-injection Carrier Current AM system in the future...


-- Jason

 

[RadioMan203]

Glad to see you'll still do a little in Part 15. I know this was one of the reasons I was so happy to finally get my own place. Alaska must present its own fun when it comes to external wiring, especially with the climate there.

Please keep us up to date if you try the carrier current operation within your building. I'm still looking for someone to profile who is using carrier-current technology for Part 15 AM.

 

[Tom Wells]

Why wouldn't you be able to just put your radiating element inside an exterior wall?

Tell us about the constuction of the building and apartment, and maybe we can help you get a decent signal out on AM pt 15.

Is there any metal plumbing?
Is the wiring in metal conduit or not? If it is, carrier current operation is not going to be very effective.

I was lucky enough to have a landlord that let me put a 40m dipole on the roof of the building back when I had the pirate station.

Are you on the ground floor?

Have you ever tried (ahem) mild coupling into telephone lines? 100mw should not be able to leak into anyone's conversation.

Bill, doesn't the carrier current system have some problem with hum modulation if the receiver is plug-in and has poor RF bypassing
in the power supply?
I know I get enough of that without being carrier current.

I don't get any hum pickup in battery radios, but only the cheaper plug-ins, where RF walks through the power supply.

 

[RadioMan203]

Bill, doesn't the carrier current system have some problem with hum modulation if the receiver is plug-in and has poor RF bypassing in the power supply? I know I get enough of that without being carrier current.

I don't get any hum pickup in battery radios, but only the cheaper plug-ins, where RF walks through the power supply.

In my recent testing of a carrier current system the test receivers didn't present the hum modulation issue you speak of, although I had seen systems where this is quite possible. Judging from the recent test most modern receivers I had access to appear to tolerate the hum to the point where it was either non-existent or at such a level that didn't significantly impact the listenability of the audio. I discovered on a small campus with many power transformers within the building that both the signal gets stopped quite often and hum is a greater issue. This may be the case in a typical apartment building depending on the construction and power distribution systems employed.

 

[Black_Shire]

TO BILL -- For radio, apartments have their drawbacks (ask any ham operator!), but on the other hand I don't have to cut the grass or sweep the snow off the driveway and walkway anymore!

Even vehicles here have what is called "arctic insulation" on their ignition wires, because over time the regular insulation gets freeze-dried, cracks, and eventually separates from the conductor. (It happened to my pickup truck that I brought here from Miami.)

I'll keep you posted on any Carrier Current setup. First I'll need to build an AC line coupler to go with the Radio Systems transmitter, but James Cunningham's book (see: http://groups.msn.com/GospelRadio/lowpoweramradiothebook.msnw ) and his web site (see: http://groups.msn.com/GospelRadio/carriercurrenttuning.msnw and http://groups.msn.com/GospelRadio/carriercurrentbroadcasting.msnw ) have lots of information on home-brewed Carrier Current equipment as well as Part 15 AM broadcasting.

TO TOM -- I live on the second story in disabled/elderly housing, and we're not allowed to "modify" the walls beyond putting in nails to hang up pictures. The building structure is concrete with lots of steel rebar (it was built after the huge 1964 earthquake down in Anchorage).

The plumbing is all metal, but I don't know if the wiring is in conduits or not (although judging by the robust construction, I'd guess that it probably is in conduits). How, um...hypothetically, of course......would one best couple a 100 mW AM signal into the telephone lines? (The building also has Cable TV coax in the walls...)

You're lucky--we aren't even allowed on the roof, and the access door is alway locked! (Maybe they're afraid of suicide jumps by depressed residents?)

I toyed with the idea of capacitive coupling through one of the sealed, non-openable windows to feed the signal to an antenna mounted outside on the balcony, but the losses through the window capacitor would probably be substantial, plus gluing foil to the windows is verboten. A multi-turn flat square spiral loop antenna (as opposed to a box loop antenna) hung up in front of a window might work, since spiral loops (if I recall correctly) radiate in directions perpendicular to the plane of the loop.


-- Jason