BNC Connector

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k-mob

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I waited too long this and had to end up buying a Signtek knockoff from Amazon (I hesitate to use the word cheap, because it wasn't that cheap, and I'm thinking I should have gotten something even cheaper).

Anyway, I'm not happy with the range on it, so I wanted to play around with a dipole antenna or something. The (female) antenna connector claims to be BNC, but instead of the normal posts associated with BNC, the other circumference is actually threaded. So you can screw the antenna on, but I can't find any other compatible connector anywhere that I can hook up to coax or whatever and run outside and connect to a different antenna.

Does anyone have any experience with this? Any ideas for how to break this out to a more traditional connector?

P.S. I naively thought that turning up the audio volume would help with the transmission distance, but it turns out my poorest performance was just from distortion. I got better reception with the audio volume turned down somwhat.
 
It's probably TNC. I've got two signstek transmitters that are supposedly the same, but one has BNC and one has TNC for the antenna. There's simple adapters out there to go back and forth between the two types
 
I've just recently had to replace my transmitter too. I bought the Signtek as well. It came w/ a TNC connector. I also, just built a dipole antenna and love the results.
From the old IPX/SPX networking days, I still have a bunch of 50ohm BNC cables. So I bought this --> Amazon TNC to BNC adapter
I cut one of the BNC Cables I had to use for the antenna itself w/ a bnc coupler at the end. Then I mounted a cover plate w/ a BNC coupler (Monoprice Keystone Jack-Modular BNC) in my garage ceiling to the attic and mounted the antenna up there. I just use 2 BNC patch cords to connect the transmitter to the ceiling plate, then the ceiling mount to the antenna.
Building the antenna, I tried a couple of times. First, I used solid copper thermostat wire, 19awg? Had ok results. I didn't like the way it came out anyways, so rebuilt it using 14awg electric wire. Mounted it in my attic and I've never had a better signal.
 
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Thanks for all of the feedback! I was going to post pics, but having looked into what TNC is, yes, it is almost certainly a TNC connector, so thank you. The Amazon website had called it a BNC, so I was stuck looking for threaded BNC which was not getting me anywhere. Now that I know what to call it, getting a converter will be much easier.

As for the links, thank you, those should give me a good start on improving things as is (and help to explain why my lower volume was performing better).

My attempt at a dipole was unproductive; might be better with an actual proper connection + coax. Is there any reason I shouldn't make the dipole out of braided copper? Cmndr Brain, I assume your 14 awg wire was braided? Do you attribute the improved performance to the lower gage?
 
I personally would recommend a ground plane antenna.
I would also say, that the use of 50 OHM coax is the best between the transmitter and the antenna. (this is NOT TV coax).
I'd also recommend this antenna that (hold on to your seat) Is MADE IN AMERICA!
I have one and its well made.
I'm always surprised how folks will spend thousands of dollars on pixels and controllers and then put in a $10 FM transmitter and crappy antenna.
I've run a 1/4 wave ground plane antenna with a 10mw transmitter and get a nice clear sound for 1/4 of a mile.
https://centerfireantenna.com/tunable-87-108-mhz-fm-band-broadcast-antenna/

k-mob said:
Thanks for all of the feedback! I was going to post pics, but having looked into what TNC is, yes, it is almost certainly a TNC connector, so thank you. The Amazon website had called it a BNC, so I was stuck looking for threaded BNC which was not getting me anywhere. Now that I know what to call it, getting a converter will be much easier.

As for the links, thank you, those should give me a good start on improving things as is (and help to explain why my lower volume was performing better).

My attempt at a dipole was unproductive; might be better with an actual proper connection + coax. Is there any reason I shouldn't make the dipole out of braided copper? Cmndr Brain, I assume your 14 awg wire was braided? Do you attribute the improved performance to the lower gage?
Click to expand...
 
k-mob said:
My attempt at a dipole was unproductive; might be better with an actual proper connection + coax. Is there any reason I shouldn't make the dipole out of braided copper? Cmndr Brain, I assume your 14 awg wire was braided? Do you attribute the improved performance to the lower gage?
Click to expand...

No, the 14awg wire I used was just from regular Romex electric solid wire. I just happen to have a 4ft piece lying around.

I used this -> https://www.doityourselfchristmas.com/wiki/images/a/a7/How_to_make_a_dipole_antenna.pdf
as the guideline for making the antenna. My center piece was just a piece of fiberglass pcb perf board. I used this calculator, https://www.everythingrf.com/rf-calculators/dipole-antenna-length-calculator to get the length of one of the legs and made two of them the same length based off the FM frequency I'm using.
As far as the improved performance, I think it was more of just taking my time to make the antenna and raising the height into my attic. I've read articles on the debate of whether or not to use 50ohm network wire or 75ohm RGx coax. The articles I've read seem to conclude it makes no difference, but I'm not a RF guy. Other may argue otherwise. I happen to have 50ohm BNC coax from the old networking days that I don't think will ever be used again, so I put it to good use.
Mine is also mounted horizontally in the attic section that overhangs my front door. Horiz/Vert didn't make a difference for me.

ukewarrior said:
I'm always surprised how folks will spend thousands of dollars on pixels and controllers and then put in a $10 FM transmitter and crappy antenna. I've run a 1/4 wave ground plane antenna with a 10mw transmitter and get a nice clear sound for 1/4 of a mile.
Click to expand...
Ground plane is certainly a better antenna. But, for me, it wasn't about the price, it was about being able to mount the thing. I didn't want the antenna outside for a couple of reasons. 1) All my electronics is mounted in the garage, the antenna is in the attic directly above the equipement. 2) I didn't have the space for an antenna that large in my attic and I didn't want it outside. But, if you certainly have the space, go for it.
 
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