Repeater 2.3 miles away, can hear clearly, can't hit it.

[WSCB609]

But the same radio and antenna will hit another repeater 6 miles away different direction.

I know my tone and offset is correct.   (Both repeaters have same tone / offset) just different freq.

There is a slight hill+house+trees in between us, so my line of sight is questionable.  Even tried  Yagi  pointed that way.  I'm 20watts and swr is 1.2. 

If the hill is a problem transmitting, why not receiving?

[OffRoaderX]

1 minute ago, WSCB609 said:

If the signal is blocked LOS one way, why not the other? 

Because you dont have the exact same equipment/antenna/power/whatever going both ways?

[OffRoaderX]

5 minutes ago, WSCB609 said:

my line of sight is questionable

Looks like you answered your own question. 

There are only two possibilities: 

1. You have a setting wrong
2. Its out of range/out of LOS

[WSCB609]

20 minutes ago, OffRoaderX said:

Looks like you answered your own question. 

There are only two possibilities: 

1. You have a setting wrong
2. Its out of range/out of LOS

If I move the antenna 25 ft to the south, same height, it will hit the repeater, forgot to add that part.  So settings are correct.    My question is , if LOS is that critical, why can I hear it full clear in its current location?  (25' north of where I can hit it.)  But can't hit it now ? 

[OffRoaderX]

1 minute ago, WSCB609 said:

 My question is , if LOS is that critical, why can I hear it full clear in its current location?  (25' north of where I can hit it.)  But can't hit it now ? 

Because sometimes that's just how radio-waves work.  Not sure what other answer your looking for.

[WSCB609]

5 minutes ago, OffRoaderX said:

Because sometimes that's just how radio-waves work.  Not sure what other answer your looking for.

If the signal is blocked LOS one way, why not the other? 

[Socalgmrs]

This is how this works some times.  You have a repeater or even another base station up high with a good antenna coax and 50w radio  that can be heard from 50-60-100 miles away but not every one in those areas that can hear it are going to be able to hit it.  It might be height, line of sight, antenna, coax, radio…  the list goes on but this is totally normal.   Some people can hit everything and some can’t.  

[WSCB609]

49 minutes ago, Socalgmrs said:

This is how this works some times.  You have a repeater or even another base station up high with a good antenna coax and 50w radio  that can be heard from 50-60-100 miles away but not every one in those areas that can hear it are going to be able to hit it.  It might be height, line of sight, antenna, coax, radio…  the list goes on but this is totally normal.   Some people can hit everything and some can’t.  

But 2.5 miles away? If I move antenna 25 foot south, I can hit it.   But 25' north of that location, I can hear full clear, but not hit it.   I'm trying a J-pole and an Yagi.
That makes no sense.  PS, another repeater 6.5 miles in another direction, I can hit it full clear with same radio/antenna.

[piggin]

42 minutes ago, WSCB609 said:

But 2.5 miles away? If I move antenna 25 foot south, I can hit it.   But 25' north of that location, I can hear full clear, but not hit it.   I'm trying a J-pole and an Yagi.
That makes no sense.  PS, another repeater 6.5 miles in another direction, I can hit it full clear with same radio/antenna.

It is because the repeater has an antenna that has a different pattern than yours...and also probably more ERP than your setup. Its a normal occurrence on UHF.

 If you use 50 watts that might do it. In the absence of direct LOS you are using  diffraction to get into the repeater. To use an analogy...car headlights approaching you at night beyond a hill between you are brighter to you if they have a tight spot aimed at the hill apex and are really powerful. If you are running low beams and weak lights the other driver won't even know you are there. Distance isn't the limiting factor. LOS occlusion and pattern combined with power are.

 I hope this helps.

[AdmiralCochrane]

I wouldn't bring diffraction into the conversation.  Most likely just an obstruction than different antenna pattern. 

[WSCB609]

58 minutes ago, AdmiralCochrane said:

I wouldn't bring diffraction into the conversation.  Most likely just an obstruction than different antenna pattern. 

That's what I think, but I don't understand one way obstruction   .  Like a diode.  

[SteveShannon]

3 hours ago, WSCB609 said:

That's what I think, but I don't understand one way obstruction   .  Like a diode.  

As @OffRoaderX said, sometimes it works that way. 
Let’s say you’re hiding behind a rock. Someone 100 feet away is pointing an elevated spotlight towards your rock. At that range the beam spreads out larger than the rock and you can see it reflecting off your surroundings. But you shine a flashlight directly at the rock in the direction of the spotlight and they don’t see you at all. 
It’s very common for radio communications to propagate asymmetrically.