BC-246T/CloseCall Antenna experiment

[CZ]

Connected the 246T (Firmware 1.42) to about 25 feet of wire, then set CloseCall up to "Close Call Only" > "Search and Store" with Autostore limit of 25.

Let it run for about an hour, then went over to Scan > Hold and tuned manually to see what CloseCall had picked up, and found that it had picked up / stored nothing

I was copying signals quite well with the wire scanning normally before and after the experiment, though.

 

[ILbandit]

I was curious about the same thing, Wondering if hooking up a good external antenna would make the close call function pull in signals better.

 

[mciupa]

Why not check out some band specific antennae ? VHF,UHF, 800 mHz
Is there a particular search range you like to check out? ... or are you doing a broad search , looking for anything that pops up.

 

[UPMan]

You still need a signal about 15 dB above the RF floor in each band to trigger a CC hit. By using a "better" antenna, you are also raising the RF floor as well as "target" signal levels. I wouldn't expect any great range improvements.

You'd have better luck dialing 911 a few times (all sorts of radios will get keyed up closer to your house when you do that).

 

[Saint]

re-close call

I was curious about the same thing, Wondering if hooking up a good external antenna would make the close call function pull in signals better.

No it won't, all you will do is pick up mostly FM Stations in the back ground.
Steve

 

[scanfan03]

Remember people, Close Call is a frequency counter, not a search. You have to be right up close to the transceiver (handhelds) to get a hit from it. Like someone already said the signal has to be 15 dB above the RF floor to get a hit.

 

[CZ]

Granted, there was a pretty good impedance difference between a duck or outside antenna & the wire, but I should have logged something -- even kids using FRS radios in the Complex

I live in a 2nd. story apartment, and the antenna ran across a window, and was about 2 feet from the ceiling thru rest of its length.

What was interesting (to me anyway) was comparing the difference in signal strength between the Duck that came with it & the wire -- the signal would come up noticeably with the wire on most frequencies I was scanning before I tried a CloseCall scan.

Wire didn't seem to help aircraft reception though (I'm about 5 miles from the Tower, & on edge of glidepath), but noticed the Tower wasn't too active before I tried a CloseCall.

 

[Voyager]

You still need a signal about 15 dB above the RF floor in each band to trigger a CC hit. By using a "better" antenna, you are also raising the RF floor as well as "target" signal levels. I wouldn't expect any great range improvements.

I would have to SLIGHTLY disagree with that. If you use an antenna tuned to the band of interest, you can raise the signals in that band much more than those in other bands (especially lower frequency bands). Although the increase may not be that great, there would be a noticable increase of in-band CC activity.

I've used this method of a 'poor man's preselector' on my Scout for years with great success. Signals in the resonnant band always increase.

I would agree that your in-band noise floor SHOULD increase by the same level as your target signal, but in reality you do get more hits (most likely due to the decreased 'noise floor' created by out-of-band transmitters)

BTW, who is Pedro?

Joe M.

 

[UPMan]

Well, there are 5 distinctly filtered bands, and 5 disctinct CC checks (assuming you have all of them enabled)--one in each of those bands. So, the effect you are describing isn't going to be as great as if the scanner were looking at the entire spectrum at once with no filtering.

You need to watch Napoleon Dynamite, Gosh!

============================================
"Don't be jealous that I've been chatting online with babes all day. Besides, we both know that I'm training to be a cage fighter."

 

[Voyager]

Well, there are 5 distinctly filtered bands, and 5 disctinct CC checks (assuming you have all of them enabled)--one in each of those bands. So, the effect you are describing isn't going to be as great as if the scanner were looking at the entire spectrum at once with no filtering.

You need to watch Napoleon Dynamite, Gosh!

What channel is that on, and OK about the bandpass filters. I haven't tried it much on the BC246T, but I know it works great on the Scout. But then, the Scout doesn't have 5 distinctly filtered bands. :wink:

So, when in the frequency counter 'test mode', which ones are enabled?

Joe M.

 

[N_Jay]

Does that 15 dB number come from the manual, or is it a guess?

 

[UPMan]

Its a movie...Blockbuster.

15dB is estimate from memory, not scientific.

Test mode isn't documented anywhere that I have the language skills to read. お疲れさまです。

 

[CZ]

Errr, discovered why I didn't find any frequencies. I forgot to turn on "Auto Store" Will try the experiment again & see what happens.

 

[ILbandit]

I forgot to turn on "Auto Store"

LOL, yeah, that would explain alot. :lol: