Need help please

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hawkeye32

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Ok i received my scantenna today (ST2) and i was under the assumption it had a PL-259 connector on it but it does not...It just has a regular cable plug in (same kind that is on the back of a tv), thou i can remove it by undoing the wing nuts..My question is i have a discone here that has a PL-259 connector on it how can i put this on my ST2 , i've tried looking over the antenna but can't find a screw in for it, if it is not possible , i have some LDF1-50 Heliax coax coming (75feet) now before it gets shipped could i do this: have a regular cable plug in with a BNC on the other end?? and will this be good to do?? Or if anyone has any suggestions on how i can use my PL-259 connector on my ST2 that be great too...Open for any suggestions
 

radiopro52

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If the end of your coax has a PL-259 connector, or UHF male, on it then I would use an F to UHF female adapter like this one. If you need a male F adapter there are those too, like this one.
 
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hawkeye32

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I have what u posted already at least i think i do, everything looks the same but on the "bolt end" it just screws in no plug can attach to it, now if this is the correct adapter their is no way of attaching it to my ST2 ,this is what is currently on the ST2 http://kalx.berkeley.edu/recept/images/balun.gif

Now that is attached to the wingnuts ,but my PL-259 adapter is one bolt to screw in no where on the ST2 can i plug this into, any ideas???
 

af5rn

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This is probably the biggest problem with the Scantenna. It's made by people whose primary business is television broadcast antennas, who don't seem to grasp the concepts of resistance and RF loss. You're transforming a 300ohm antenna down through a very lossy 75ohm transformer, then attaching it all to 50ohm coax, using 75ohm connectors. Bad juju.

You'll have to search around the net, because Rat Shack does not carry them, but what you need is a UHF jack-to-F plug inline adapter. I don't even see them on the Amphenol website, so there may not even be such an animal. You're probably going to have to use a piece of jumper coax, with one end having an F connector, and the other having a UHF female connector on it, to go between that 300ohm transformer and your coax, and accept the resulting RF loss inherent in connectors and jumpers.

I'm actually kind of surprised that Antennacraft didn't convert this silly thing to a 50 ohm antenna with the last "new improved" version. Apparently, not enough scannists know the difference to complain.

EDIT: The second adapter that radiopro52 posted is exactly what you need! Good work, 52! I was busy looking it up when you posted apparently.

You better weather-seal the hell out of it though. Good luck!
 
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radiopro52

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hawkeye32 said:
I have what u posted already at least i think i do, everything looks the same but on the "bolt end" it just screws in no plug can attach to it, now if this is the correct adapter their is no way of attaching it to my ST2 ,this is what is currently on the ST2 http://kalx.berkeley.edu/recept/images/balun.gif

Now that is attached to the wingnuts ,but my PL-259 adapter is one bolt to screw in no where on the ST2 can i plug this into, any ideas???
Then you would need the F male adapter, like the one I linked to in my previous post. That should work. Just plug the male UHF plug into the adapter, and then connect that to the ST2. Also, about your heliax coax coming in, you should have a male F connector on one end and the other end would be the connector to connect to your scanner, which would probably be a male BNC.
 

af5rn

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That is not nearly as good a choice as what radiopro52 linked you to above. BNC is lossy and impossible to weatherproof. The UHF connector you originally told us you had is a much better choice. But yeah, if your coax has suddenly changed from PL-259 to BNC, that will work.
 

hawkeye32

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Yes i do understand that unfortunatley here in windsor or canada should say we no longer have a radio shack its called "the source" now, i went to their and looked to see if they have the connector for the PL-259 to the transformer but they did not, they told me they no longer carry them, so basically had no choice to get what i had to get, as for weather proofing , maybe just wrap it in silicon or something
 

hawkeye32

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Thanks everyone for the feedback as it has helped me hopefully solve my issue, won't really know until i receive my coax and set everything up, Now i have seen a couple threads here that folks are having issues with the civ air band (108-138mhz) I have the BC898t, what i am not sure of is if their are towers, antennas around me that could cause interference, as for looking around i see none in my area...Is their a site that lists say towers, antennas around here, i am in windsor ontario canada
 

VA3QRM

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Downtown Windsor Hawkeye?

I think if you are close to Downtown or a paging site, intermod 'might' be a problem, I suspect that is the 'interference' that is being spoke of. Hook it up and enjoy, hopefully no issues.
 
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zz0468

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af5rn said:
That is not nearly as good a choice as what radiopro52 linked you to above. BNC is lossy and impossible to weatherproof. The UHF connector you originally told us you had is a much better choice. But yeah, if your coax has suddenly changed from PL-259 to BNC, that will work.

BNC connectors can be rated up to 10 GHz and, as a constant-impedance connector, are considerably less lossy than a standard "UHF" type. I can't understand why you would think the latter is a better connector. It is not. A PL-259 is only really useful up to a few hundred MHz before performance starts getting weird. It was designed prior to WW2 when "UHF" meant above 30 MHz.

To the op: There really is no reason to want to change the scanntenna connector. The 'F' type cable connector is actually VERY decent. There is a reason why cable companies use it for their entire infrastructure - it is an EXCELLENT connector, RF performance wise, and it has the added benefit of being inexpensive.

In general, the 50 to 75 ohm impedance mismatch is so completely insignificant for a receive antenna. Just get an adapter to go from whatever is on the end of the cable to the 'F' connector on the antenna and don't worry about the losses. The manufacturer probably continues to use it because it allows people to use standard, readily available TV coax and connectors.
 

N1BHH

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Radio Shack has adapters, your local electronics shop has adapters. You can find them at your local hardware store. Oh yeah, most of them are gone, nut adapters are abundant. I go to You Do It Electronics in Needham, MA. for all my connectors and adapters. Heck, you can by "F" connectors by the pound for pennies. "F" connectors are everywhere and cheap.
 

hawkeye32

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VA3QRM said:
I think if you are close to Downtown or a paging site, intermod 'might' be a problem, I suspect that is the 'interference' that is being spoke of. Hook it up and enjoy, hopefully no issues.


I live near the forest glade area haven't seen any towers nor antennas at least visible,only one really i have seen is the one at the OPP base in tecumseh
 

VA3QRM

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I think you should be in good shape re: intermod from paging systems. As I said before, with some height and the low loss cable you should be in business. Enjoy. How high up is your antenna going?
 

Lowa2

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hoser147 said:
Why would a Bnc be any harder to seal up than any other connector, Ive had one outside for quite a while now and no problems?? Hoser


what ^^ said.
 
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