RE: [Repeater-Builder] Re: De-sense question

2009-09-07 Thread Eric Lemmon 
Konstantinos,

First go to the Repeater-Builder Technical Information Pages (RBTIP) here:

Then scroll down to the Search box, enter "desense", and click the search
button.

73, Eric Lemmon WB6FLY
 

-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of Konstantinos Hatzakis
Sent: Monday, September 07, 2009 8:05 AM
To: Repeater-Builder@yahoogroups.com
Subject: Re: [Repeater-Builder] Re: De-sense question

  

Dear Mike !

Would you mind give me the relative Link because I am not so familiar with
the RB site .

Many Thanks !

Konstantinos

SV9LN  Crete Greece

Re: [Repeater-Builder] Re: De-sense question

2009-09-07 Thread Konstantinos Hatzakis 
Dear Mike !

Would you mind give me the relative Link because I am not so familiar with the 
RB site .

Many Thanks !

Konstantinos

SV9LN  Crete Greece



  - Original Message - 
  From: Mike Besemer (WM4B) 
  To: Repeater-Builder@yahoogroups.com 
  Sent: Monday, September 07, 2009 5:37 PM
  Subject: RE: [Repeater-Builder] Re: De-sense question



  There's a great document on the RB website that discusses desense.  If you 
haven't looked at it, I'd definitely recommend it.



  73,



  Mike

  WM4B




--

  From: Repeater-Builder@yahoogroups.com 
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of jmp46534
  Sent: Monday, September 07, 2009 10:26 AM
  To: Repeater-Builder@yahoogroups.com
  Subject: [Repeater-Builder] Re: De-sense question





  Thanks Oz for the comments.

  You are right it could be the duplexer, but my money is still on that used 
antenna. 

  I know when I moved the duplexer to here, I had it wrapped in a blanket and 
strapped in to the car seat like a baby.

  I found a document on hooking a handheld to the transmit side and adjusting 
for maximum output. Guess that is my next step since I don't have a service 
monitor.

  73
  John

  --- In Repeater-Builder@yahoogroups.com, Rich Osman  wrote:
  >
  > John,
  > 
  > Some comments and observations;
  > 
  > Moving a 30 or 40 year old might radio invalidate the fact that it was
  > "working at the other site."
  > 
  > Duplexers, particularly 'vintage' duplexers don't always travel well. 
  > This is particularly true when the person doing the alignment forgets to
  > run the locking nuts in... (Of course I've never done this.)
  > 
  > Of course **I've** never made a mistake reconnecting stuff after a
  > radio's been moved, either. ;-)
  > 
  > The idea of a binary search is valid and lets you verify the facts you
  > think you know. It doesn't hurt to prove that it's the site and not the
  > radio. 
  > 
  > Finally, remember what happens when you assume...
  > 
  > Oz
  > 
  > jmp46534 wrote:
  > > 
  > >
  > > Thanks guys for all the answers and suggestions.
  > >
  > > I will try most of them, probably not the isolator until we can find one.
  > >
  > > The interconnecting cables for the duplexer are from Wacom and are a
  > > matched set of RG214 that came with the 6 cans. I also have RG214
  > > going from the cans to radio and bandpass.
  > >
  > > The radio was tuned using a service monitor by the Ham that set up all
  > > of equipment. He owns multiple repeaters and does know what he is doing.
  > >
  > > It worked fine when it was on his tower. The only changes have been
  > > the coax and antenna now that it is here on our tower.
  > >
  > > That is why I am thinking it must be in the antenna.
  > >
  > > Oh, I am using a Daiwa CN 801 wattmeter/swr meter with a RG214 cable.
  > >
  > > Off to try some of your ideas.
  > > Thanks and 73
  > >
  > > John, W3ML
  > >
  > > 
  > 
  > 
  > -- 
  > mailto:o...@... 
  > Oz
  > POB 93167 
  > Southlake, TX 76092 (Near DFW Airport)
  >

RE: [Repeater-Builder] Re: De-sense question

2009-09-07 Thread Andrew Seybold 
What happens if you use the bandpass and the duplexor on the other 2M
antenna? Do you get the same results? If so then you know that it is
either the coax or the antenna, but if you get the same results-then you
can bet you need to look elsewhere-keep at it-and keep listening to the
folks on here-we all have pulled our hair out a few times with similar
problems-and at some point we figure it out and fix it-

Andy

 

From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of jmp46534
Sent: Monday, September 07, 2009 7:45 PM
To: Repeater-Builder@yahoogroups.com
Subject: [Repeater-Builder] Re: De-sense question

 

  

Correct Andy,

As they say I might have won the battle but the war is not over. 

I still need to come up with the why it is happening. Then the solution.

My next attempt is to take the bandpass out of line and try it just
through the duplexer with the antenna hooked back to both sides.

Can't hurt anything.

73
John

--- In Repeater-Builder@yahoogroups.com
 , "Andrew Seybold"
 wrote:
>
> Good news John, I trust that the receive antenna is higher than the
> transmit antenna? And it appears from what you said that the vertical
> separation is sufficient to take care of the de-sense issue-HOWEVER,
> that does not mean that your transmitter is clean, only that you have
> found a cure for your problem, if there are other radios at the same
> site you might be causing them interference also, fixing your own
> problem is only part of the fix-fixing the underlying issue is the
most
> important thing-but at least you have a work around for now.
> 
> Good Luck
> 
> 
> 
> Andy W6AMS
> 
> 
> 
> From: Repeater-Builder@yahoogroups.com
 
> [mailto:Repeater-Builder@yahoogroups.com
 ] On Behalf Of jmp46534
> Sent: Monday, September 07, 2009 6:52 PM
> To: Repeater-Builder@yahoogroups.com
 
> Subject: [Repeater-Builder] Re: De-sense question
> 
> 
> 
> 
> 
> We did discover that the receive works great when the transmitter is
> attached to another antenna.
> 
> Receive strength went way up. But, of course that doesn't fix the
> problem of wanting to use only one antenna.
> 
> So for now, the receive will be on the repeater antenna and the
transmit
> on a separate 2 meter antenna.
> 
> Thanks for all the advice.
> 
> 73
> John
>

RE: [Repeater-Builder] Re: De-sense question

2009-09-07 Thread Andrew Seybold 
Good news John, I trust that the receive antenna is higher than the
transmit antenna? And it appears from what you said that the vertical
separation is sufficient to take care of the de-sense issue-HOWEVER,
that does not mean that your transmitter is clean, only that you have
found a cure for your problem, if there are other radios at the same
site you might be causing them interference also, fixing your own
problem is only part of the fix-fixing the underlying issue is the most
important thing-but at least you have a work around for now.

Good Luck

 

Andy W6AMS

 

From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of jmp46534
Sent: Monday, September 07, 2009 6:52 PM
To: Repeater-Builder@yahoogroups.com
Subject: [Repeater-Builder] Re: De-sense question

 

  

We did discover that the receive works great when the transmitter is
attached to another antenna.

Receive strength went way up. But, of course that doesn't fix the
problem of wanting to use only one antenna.

So for now, the receive will be on the repeater antenna and the transmit
on a separate 2 meter antenna.

Thanks for all the advice.

73
John

Re: [Repeater-Builder] Re: De-sense question

2009-09-07 Thread no6b 
At 9/7/2009 09:07, you wrote:

>If I were you, the first thing I would do is to remove the pre-amp. Then, 
>put a GOOD dummy load on the output of the duplexer. Next have one of the 
>helpers walk around with a handheld and go for a walk until they get noisy 
>into the repeater. Next, monitor the local speaker audio and compare it 
>with the repeat audio to see if they are the same. This allows you to 
>determine if the antenna and feedline is working properly.

I'm lost: how does comparing the local repeater RX speaker & repeat audio 
tell you anything about the antenna system?  Perhaps if you turn the TX off 
& on while listening to the local audio you could hear any desense, but you 
don't need repeat audio for that.

Bob NO6B

Re: [Repeater-Builder] Re: De-sense question

2009-09-07 Thread Chuck Kelsey 
Trying to tune a duplexer with an HT is almost certain to give you more 
problems than you already have.

Chuck
WB2EDV


   

--

  From: Repeater-Builder@yahoogroups.com 
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of jmp46534
  Sent: Monday, September 07, 2009 10:26 AM
  To: Repeater-Builder@yahoogroups.com
  Subject: [Repeater-Builder] Re: De-sense question

   



  Thanks Oz for the comments.

  You are right it could be the duplexer, but my money is still on that used 
antenna. 

  I know when I moved the duplexer to here, I had it wrapped in a blanket and 
strapped in to the car seat like a baby.

  I found a document on hooking a handheld to the transmit side and adjusting 
for maximum output. Guess that is my next step since I don't have a service 
monitor.

  73
  John

  --- In Repeater-Builder@yahoogroups.com, Rich Osman  wrote:
  >
  > John,
  > 
  > Some comments and observations;
  > 
  > Moving a 30 or 40 year old might radio invalidate the fact that it was
  > "working at the other site."
  > 
  > Duplexers, particularly 'vintage' duplexers don't always travel well. 
  > This is particularly true when the person doing the alignment forgets to
  > run the locking nuts in... (Of course I've never done this.)
  > 
  > Of course **I've** never made a mistake reconnecting stuff after a
  > radio's been moved, either. ;-)
  > 
  > The idea of a binary search is valid and lets you verify the facts you
  > think you know. It doesn't hurt to prove that it's the site and not the
  > radio. 
  > 
  > Finally, remember what happens when you assume...
  > 
  > Oz
  > 
  > jmp46534 wrote:
  > > 
  > >
  > > Thanks guys for all the answers and suggestions.
  > >
  > > I will try most of them, probably not the isolator until we can find one.
  > >
  > > The interconnecting cables for the duplexer are from Wacom and are a
  > > matched set of RG214 that came with the 6 cans. I also have RG214
  > > going from the cans to radio and bandpass.
  > >
  > > The radio was tuned using a service monitor by the Ham that set up all
  > > of equipment. He owns multiple repeaters and does know what he is doing.
  > >
  > > It worked fine when it was on his tower. The only changes have been
  > > the coax and antenna now that it is here on our tower.
  > >
  > > That is why I am thinking it must be in the antenna.
  > >
  > > Oh, I am using a Daiwa CN 801 wattmeter/swr meter with a RG214 cable.
  > >
  > > Off to try some of your ideas.
  > > Thanks and 73
  > >
  > > John, W3ML
  > >
  > > 
  > 
  > 
  > -- 
  > mailto:o...@... 
  > Oz
  > POB 93167 
  > Southlake, TX 76092 (Near DFW Airport)
  >

Re: [Repeater-Builder] Re: De-sense question

2009-09-07 Thread Chuck Kelsey 
I agree. The connectors should have screwed on with your fingers. Then you 
can snug them a little with pliers or a wrench.

Chuck
WB2EDV


- Original Message - 
From: 
To: 
Sent: Monday, September 07, 2009 10:48 AM
Subject: Re: [Repeater-Builder] Re: De-sense question


> In your initial post ypu mentioned that you had to use pliers to
> tighten the connectors on both ends.
>
> 2 possibilities:
> 1) You used the wrong connectors.
> Yes I have seen this done before.  A PL259 screwed onto a N-Female.
> Contact made but poor range on a simplex system; looked OK on wattmeter.
> 2) You have cross-threaded the connections.  There is contact but it
> is poor/intermittent.  Another good place for problems.
>
> The connectors should screw together by hand.  If they don't there is
> a problem.  Find it and correct it.  Don't use the pliers for anything.
>
> Also, as others have said, get rid of the preamp.
>
> Milt
> N3LTQ
>
>

RE: [Repeater-Builder] Re: De-sense question

2009-09-07 Thread Butch Kanvick 

John.

You should use a Network Analyzer like a IFR 7550A with a tracking generator to 
properly adjust the Duplexer, unless the service monitor has a Tracking 
Generator in it.

 

Have a great Labor Day.

 

Butch, KE7FEL/r
 


To: Repeater-Builder@yahoogroups.com
From: w...@arrl.net
Date: Mon, 7 Sep 2009 14:25:41 +
Subject: [Repeater-Builder] Re: De-sense question

  



Thanks Oz for the comments.

You are right it could be the duplexer, but my money is still on that used 
antenna. 

I know when I moved the duplexer to here, I had it wrapped in a blanket and 
strapped in to the car seat like a baby.

I found a document on hooking a handheld to the transmit side and adjusting for 
maximum output. Guess that is my next step since I don't have a service monitor.

73
John

--- In Repeater-Builder@yahoogroups.com, Rich Osman  wrote:
>
> John,
> 
> Some comments and observations;
> 
> Moving a 30 or 40 year old might radio invalidate the fact that it was
> "working at the other site."
> 
> Duplexers, particularly 'vintage' duplexers don't always travel well. 
> This is particularly true when the person doing the alignment forgets to
> run the locking nuts in... (Of course I've never done this.)
> 
> Of course **I've** never made a mistake reconnecting stuff after a
> radio's been moved, either. ;-)
> 
> The idea of a binary search is valid and lets you verify the facts you
> think you know. It doesn't hurt to prove that it's the site and not the
> radio. 
> 
> Finally, remember what happens when you assume...
> 
> Oz
> 
> jmp46534 wrote:
> > 
> >
> > Thanks guys for all the answers and suggestions.
> >
> > I will try most of them, probably not the isolator until we can find one.
> >
> > The interconnecting cables for the duplexer are from Wacom and are a
> > matched set of RG214 that came with the 6 cans. I also have RG214
> > going from the cans to radio and bandpass.
> >
> > The radio was tuned using a service monitor by the Ham that set up all
> > of equipment. He owns multiple repeaters and does know what he is doing.
> >
> > It worked fine when it was on his tower. The only changes have been
> > the coax and antenna now that it is here on our tower.
> >
> > That is why I am thinking it must be in the antenna.
> >
> > Oh, I am using a Daiwa CN 801 wattmeter/swr meter with a RG214 cable.
> >
> > Off to try some of your ideas.
> > Thanks and 73
> >
> > John, W3ML
> >
> > 
> 
> 
> -- 
> mailto:o...@... 
> Oz
> POB 93167 
> Southlake, TX 76092 (Near DFW Airport)
>

Re: [Repeater-Builder] Re: De-sense question

2009-09-07 Thread men...@pa.net 
In your initial post ypu mentioned that you had to use pliers to  
tighten the connectors on both ends.

2 possibilities:
1) You used the wrong connectors.
Yes I have seen this done before.  A PL259 screwed onto a N-Female.   
Contact made but poor range on a simplex system; looked OK on wattmeter.
2) You have cross-threaded the connections.  There is contact but it  
is poor/intermittent.  Another good place for problems.

The connectors should screw together by hand.  If they don't there is  
a problem.  Find it and correct it.  Don't use the pliers for anything.

Also, as others have said, get rid of the preamp.

Milt
N3LTQ




Quoting jmp46534 :

> Thanks guys for all the answers and suggestions.
>
> I will try most of them, probably not the isolator until we can find one.
>
> The interconnecting cables for the duplexer are from Wacom and are a  
> matched set of RG214 that came with the 6 cans. I also have RG214  
> going from the cans to radio and bandpass.
>
> The radio was tuned using a service monitor by the Ham that set up  
> all of equipment.  He owns multiple repeaters and does know what he  
> is doing.
>
> It worked fine when it was on his tower. The only changes have been  
> the coax and antenna now that it is here on our tower.
>
> That is why I am thinking it must be in the antenna.
>
> Oh, I am using a Daiwa CN 801 wattmeter/swr meter with a RG214 cable.
>
> Off to try some of your ideas.
> Thanks and 73
>
> John, W3ML
>
>
>
>
>
>
>
> 
>
>
>
> Yahoo! Groups Links
>
>
>
>

RE: [Repeater-Builder] Re: De-sense question

2009-09-07 Thread Mike Besemer (WM4B) 
There's a great document on the RB website that discusses desense.  If you
haven't looked at it, I'd definitely recommend it.

 

73,

 

Mike

WM4B

 

  _  

From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of jmp46534
Sent: Monday, September 07, 2009 10:26 AM
To: Repeater-Builder@yahoogroups.com
Subject: [Repeater-Builder] Re: De-sense question

 

  

Thanks Oz for the comments.

You are right it could be the duplexer, but my money is still on that used
antenna. 

I know when I moved the duplexer to here, I had it wrapped in a blanket and
strapped in to the car seat like a baby.

I found a document on hooking a handheld to the transmit side and adjusting
for maximum output. Guess that is my next step since I don't have a service
monitor.

73
John

--- In Repeater-Builder@ 
yahoogroups.com, Rich Osman  wrote:
>
> John,
> 
> Some comments and observations;
> 
> Moving a 30 or 40 year old might radio invalidate the fact that it was
> "working at the other site."
> 
> Duplexers, particularly 'vintage' duplexers don't always travel well. 
> This is particularly true when the person doing the alignment forgets to
> run the locking nuts in... (Of course I've never done this.)
> 
> Of course **I've** never made a mistake reconnecting stuff after a
> radio's been moved, either. ;-)
> 
> The idea of a binary search is valid and lets you verify the facts you
> think you know. It doesn't hurt to prove that it's the site and not the
> radio. 
> 
> Finally, remember what happens when you assume...
> 
> Oz
> 
> jmp46534 wrote:
> > 
> >
> > Thanks guys for all the answers and suggestions.
> >
> > I will try most of them, probably not the isolator until we can find
one.
> >
> > The interconnecting cables for the duplexer are from Wacom and are a
> > matched set of RG214 that came with the 6 cans. I also have RG214
> > going from the cans to radio and bandpass.
> >
> > The radio was tuned using a service monitor by the Ham that set up all
> > of equipment. He owns multiple repeaters and does know what he is doing.
> >
> > It worked fine when it was on his tower. The only changes have been
> > the coax and antenna now that it is here on our tower.
> >
> > That is why I am thinking it must be in the antenna.
> >
> > Oh, I am using a Daiwa CN 801 wattmeter/swr meter with a RG214 cable.
> >
> > Off to try some of your ideas.
> > Thanks and 73
> >
> > John, W3ML
> >
> > 
> 
> 
> -- 
> mailto:o...@... 
> Oz
> POB 93167 
> Southlake, TX 76092 (Near DFW Airport)
>

Re: [Repeater-Builder] Re: De-sense question

2009-09-06 Thread Rich Osman 
John,

Some comments and observations;

Moving a 30 or 40 year old might radio invalidate the fact that it was
"working at the other site."

Duplexers, particularly 'vintage' duplexers don't always travel well. 
This is particularly true when the person doing the alignment forgets to
run the locking nuts in... (Of course I've never done this.)

Of course **I've** never made a mistake reconnecting stuff after a
radio's been moved, either.  ;-)

The idea of a binary search is valid and lets you verify the facts you
think you know.  It doesn't hurt to prove that it's the site and not the
radio. 

Finally, remember what happens when you assume...

Oz

jmp46534 wrote:
>  
>
> Thanks guys for all the answers and suggestions.
>
> I will try most of them, probably not the isolator until we can find one.
>
> The interconnecting cables for the duplexer are from Wacom and are a
> matched set of RG214 that came with the 6 cans. I also have RG214
> going from the cans to radio and bandpass.
>
> The radio was tuned using a service monitor by the Ham that set up all
> of equipment. He owns multiple repeaters and does know what he is doing.
>
> It worked fine when it was on his tower. The only changes have been
> the coax and antenna now that it is here on our tower.
>
> That is why I am thinking it must be in the antenna.
>
> Oh, I am using a Daiwa CN 801 wattmeter/swr meter with a RG214 cable.
>
> Off to try some of your ideas.
> Thanks and 73
>
> John, W3ML
>
> 


-- 
mailto:o...@ozindfw.net
Oz
POB 93167 
Southlake, TX 76092 (Near DFW Airport)

Re: [Repeater-Builder] Re: De-sense question

2009-09-06 Thread JOHN MACKEY 
I've heard that many times right before I had to fix someone else's mess.

-- Original Message --
Received: Sun, 06 Sep 2009 04:32:59 PM PDT
From: "jmp46534" 
SNIP
> The radio was tuned using a service monitor by the Ham that set up all of
equipment.  He owns multiple repeaters and does know what he is doing.