Hi All - I am this close (this close) to getting a Black Cat .1 mfd 1kw capacitor in line with a fuse and a Talking House transmitter (I have four in case this one blows up) - anyone have any advice? A coupler is way out of my means right now & would like to maximize station coverage....
Hi bandit:
Carrier current in the U.S. on the band 525 to 1710kHz is regulated by F.C.C. 15.221, which sets the "maximum" of what you can achieve.
The simple setup you have described may not perform very well, for these reasons...
The coupler in carrier current does more than isolate the transmitter from the A.C. line voltage; it also provides the impedance match between the transmitter and the power line.
The Talking House (TU) transmitter is 50-ohms, and a proper coupler would always keep the transmitter at this impedance, while serving to match the A.C. line impedance, which can vary wildly from 1-ohm to over 100-ohms.
The capacitor + fuse that you describe will protect the transmitter from the high voltage, but the impedance matching will be outside of your control.
If it works well with capacitor + fuse, you will be lucky.
Also, chances are the TU does not have enough power even with a good coupler, as the usual power ranges for CC are from 2 to 30 Watts, set according to 15.221.
yes, I figured I'd have to up the power to a couple of watts. with a coupler, do you have to constantly tweak it for coverage or does the match stay? there is a schematic that includes putting a variable cap between the TH ground and the antenna - would that suffice?
I read about your system earlier Carl - do you get good range with it? I would love to cover a town with this and seems that CC is the way to go- with a few verticals to fill in areas.
Cap will be here any day... I found the idea here: http://teslapress.com/am25.html - he also mentions a variable cap in it.... near the bottom.
How did Bruce's experiement go? Is RFB ever gonna build us an affordable coupler? lol
I thought the TH was 75 ohm? Any thoughts on how I could match it with the load on my cap/fuse system?
do you know how Bruce's CC experimentations with carrier current ended? Did he get much range? RFB - have you come up with a TH coupler that I could talk with you about? I have read about your station with amazement.
Thank you so much for your reply. do you know how Bruce's CC experimentations with carrier current ended? Did he get much range? RFB - have you come up with a TH coupler that I could talk with you about? I have read about your station with amazement.
thank you Carl for you reply.... do you know how Bruce's CC experimentations with carrier current ended? Did he get much range? RFB - have you come up with a TH coupler that I could talk with you about? I have read about your station with amazement.
thank you Carl - just checking out the show and I love it! great job... thoroughly enjoying it!
This is where I got the idea....check this out... http://teslapress.com/am25.html
does a couple auto match the line or would you have to manually do it a few times a day?
also, if RFB is out there, he once discussed a TH match coupler design he was working on. I would love to hear more about it! maybe with an auto rebooting system, the TH auto-matching system can automatically match things from the wire out side (not coax)?
either way, I would love to know if you had any success with it.
What has been said is that the TH transmitter has a 50-ohm antenna but comes equipped with a 75-ohm connecting cable, with no explanation. I do not have a TH, but others will come along to comment on the impedance.
I got my coupler on eBay, and a spare coupler from a part15.us member who sold his, and other couplers come along from time to time.
The only new CC coupler comes from Radio Systems, the CP-15, about $1500.
One of our members is experimenting with building a coupler, but I'll let him explain what he's done.
I'm out of things to say on the subject, but others will pick up the slack.
Coupler business anyone?
$1500? Can a good coupler be built for under $100 parts/labor? If so, and these work as well as they might appear, let's get em manufactured and sold at a $300 price point!
OK... now back to discussion. I apologized Carl, but two messages I sent you from earlier never got posted.
thanks you so much for your help. Check out this link: http://teslapress.com/am25.html there's a coupler design at the bottom. only difference is he is using 15 watts and a variable cap to tune it. what do you think of the concept? any improvements? I am building one...
Bandit, some of your posts were caught by our site spam catcher so posting was delayed. This happens sometimes with new members. I made a tweak so it shouldn't happen again.
Neil
thanks Neil - sorry about the repeats....
To Bandit...
There are long carrier current discussions buried in the postings here on the site, and a long period when I was installing and getting checked out by the member mentioned by MRAM, RFB, who is a carrier current station operator in Casper, Wyoming, and perhaps the most knowledgable person we have on the subject.
We have about three episodes of The Low Power Hour radio program on the subject of CC, free programs, and pictures of RFB's power panel CC installation, if you scroll around at my website
http://www.kdxradio.com/lph.html
I am digging the shows for sure...
which ones are the CC episodes?
Here's my plan.
The Carrier Current Shows were not well marked at the time they were done. You might be able to find one or two of them.
What I will do between now and Monday is sort around and figure out which is what.
Also, there has been talk of doing a 4th CC show, but that depends on the clouds, stars, world events and numbers all coming into alignment as of June 3rd. Hmm?
Wait here.