Antenna problem

[SA_tx_88116]

When scanning my local police,EMS, and fire I notice that my scanner would pick up transmissions but there would be no sound or it would sound very choppy and it would eventually fade into nothing, the only way to get a good quality signal is to move the antenna to a diagonal position but sometimes this isn’t enough so yesterday I was trying to find the best position to get the best signal and I found out that laying the antenna on the table got me a better signal than when it was in the air. And also the scanner sometimes blinks a flashing T that indicates reception of talkgroup data my scanner rarely does it and compared to other videos of the pro 197 on YouTube it makes my pro 197 look terrible and unreliable. I don’t know if the antenna my local emergency services use is just bad or maybe it’s time to get a new antenna to replace my old somewhat bent stock metal whip antenna. Link to example:

 

[mmckenna]

Using those back of set antennas indoors is usually a bad idea unless you are really close to the radio system.
Gyrating the antenna around might make a difference. Probably a lot of local noise in your house that isn't helping. Modern building materials can block RF pretty well (aluminum siding, metal roof, foil vapor barrier insulation, indoor wiring, HVAC ducts, internet wiring, WiFi, etc. etc. etc.)

Move the radio closer to a window, or better yet, get an outdoor antenna.

 

[wtp]

107 (6B)	007 (7)	Kingsbury	Guadalupe	770.46875c	770.93125c	773.09375c	773.55625c	773.84375c	774.30625c	774.59375c
130 (82)	030 (1E)	Hickory Forest	Guadalupe	769.69375c	770.90625c	773.06875c	773.53125c	773.81875c	774.28125c	774.56875c
131 (83)	031 (1F)	Cibolo	Guadalupe	770.06875c	771.04375c	771.61875c	772.41875c	773.21875c	774.16875c	774.74375c
132 (84)	032 (20)	Seguin	Guadalupe	769.26875c	771.34375c	772.16875c	772.81875c	773.88125c

do you have the closest tower in ?

 

[SA_tx_88116]

107 (6B)	007 (7)	Kingsbury	Guadalupe	770.46875c	770.93125c	773.09375c	773.55625c	773.84375c	774.30625c	774.59375c
130 (82)	030 (1E)	Hickory Forest	Guadalupe	769.69375c	770.90625c	773.06875c	773.53125c	773.81875c	774.28125c	774.56875c
131 (83)	031 (1F)	Cibolo	Guadalupe	770.06875c	771.04375c	771.61875c	772.41875c	773.21875c	774.16875c	774.74375c
132 (84)	032 (20)	Seguin	Guadalupe	769.26875c	771.34375c	772.16875c	772.81875c	773.88125c

do you have the closest tower in ?

My closest tower is in cibolo

 

[SA_tx_88116]

Using those back of set antennas indoors is usually a bad idea unless you are really close to the radio system.
Gyrating the antenna around might make a difference. Probably a lot of local noise in your house that isn't helping. Modern building materials can block RF pretty well (aluminum siding, metal roof, foil vapor barrier insulation, indoor wiring, HVAC ducts, internet wiring, WiFi, etc. etc. etc.)

Move the radio closer to a window, or better yet, get an outdoor antenna.

I move my scanner to 2 different places in my house, 1st position is on my dresser in my room by the wall I move it here when I’m using my PlayStation 4 or when I just want something to listen to. 2nd position is on the dining table by a window I move the scanner here when I’m using my laptop.

 

[wtp]

mmckenna forgot to add playstation and laptop...

 

[mmckenna]

Yeah, good noise sources.

 

[SA_tx_88116]

What else could possibly affect the radio?

 

[SA_tx_88116]

Yeah, good noise sources.

And another thing I have to do to get talkgroup data is to shorten the antenna’s height by pushing the lower joint down, I just don’t get it maybe there’s a setting that I possibly could use on the scanner to improve reception.

 

[SA_tx_88116]

mmckenna forgot to add playstation and laptop...

IMG_0378 I just readjusted the antenna and the T flashes longer and more frequently tell me if you think it’s good

 

[pb_lonny]

try it closer to a window or higher on a shelf.

 

[SA_tx_88116]

try it closer to a window or higher on a shelf.

Ok

 

[mmckenna]

And another thing I have to do to get talkgroup data is to shorten the antenna’s height by pushing the lower joint down, I just don’t get it maybe there’s a setting that I possibly could use on the scanner to improve reception.

Shortening the antenna is "tuning" it to be resonate on the frequencies used by the system. It's probably something like 20 inches total length? That would be resonate towards the bottom of the VHF band. Shortening it closer to 4 inches or so, or 8, etc, would make it resonate towards the 700MHz band.
Resonate antennas will work better than a random length chunk of metal, in most cases.

 

[SA_tx_88116]

Shortening the antenna is "tuning" it to be resonate on the frequencies used by the system. It's probably something like 20 inches total length? That would be resonate towards the bottom of the VHF band. Shortening it closer to 4 inches or so, or 8, etc, would make it resonate towards the 700MHz band.
Resonate antennas will work better than a random length chunk of metal, in most cases.

I just measured the antenna to be about 2ft and 1 inch

 

[K9DAK]

Try this... L=468 / F... where F is your target frequency (center of trunked system bandwidth). L is your (close enough) resonant antenna length in feet. Mine is 468 / 852.9375 MHz = 0.55 feet, or about 6.6 inches.

 

[mmckenna]

I just measured the antenna to be about 2ft and 1 inch

OK 25 inches, so probably works well down in the AM aircraft band on full extension.

 

[SA_tx_88116]

OK 25 inches, so probably works well down in the AM aircraft band on full extension.

So how should I adjust the antenna’s height for 770 to 774 MHz

 

[mmckenna]

So how should I adjust the antenna’s height for 770 to 774 MHz

Try somewhere around 3 3/4 to 4 inches, that would be pretty close to 1/4 wavelength on 772MHz. If it won't go that short, don't worry, just look at the signal meter and adjust it for maximum signal strength.

 

[SA_tx_88116]

Try somewhere around 3 3/4 to 4 inches, that would be pretty close to 1/4 wavelength on 772MHz. If it won't go that short, don't worry, just look at the signal meter and adjust it for maximum signal strength.

Ok

 

[SA_tx_88116]

Yeah, good noise sources.

And should I move squelch more to the left or right?