[Repeater-Builder] Re: Help with power supply

[jerrepotable]

--- In Repeater-Builder@yahoogroups.com, "Charles Lowery"  wrote:
>
> I purchased a Uniden 28 volt power supply today on ebay. It lookes like the 
> Astron LSRM-25A or 35A both front and back (I assume Astron made it). With 
> out seeing it I assume it works OK (cost $2.00 + shipping). Has anyone 
> converted one of these to 12 volts? I have no schematics for it and can not 
> find one on the net. If converted what would be the available current?
> 
> Charles, NM4V
>
Do you have no of model ?
or open the rig and change the zenner diode for a lower value!

[Repeater-Builder] Re: Desense on High Power Linear Repeater?

[atms169]

I have opened both repeaters.  The VHF already had the blue hardline in it, the 
UHF however I replaced with superflex.

I may try something different.  Hardline up the tower and for a patch cord 
(about 10 feet) up the mast I'll use superflex.  I'll have to play around and 
see what I have still.

The preamp has made a big impression on the RX without the amp.  I have not 
tried the system without it and the amp at the same time.  Might be worth a 
shot.

I don't have any test equipment that would work for the digital dstar so it's 
more of a trial and error thing.


--- In Repeater-Builder@yahoogroups.com, "wa1nh"  wrote:
>
> I am going to ask a question that might sound stupid but, based upon Icom's 
> ignorance, I need to ask.  
> Did you ever open the repeater case on the 2m repeater and replace the rg-58 
> patch cables that are zip tied to each other to connect the rf modules to the 
> rear of the case before adding your preamp?  Our local repeater guys had 
> serious desense and ended up replacing the junk cables with rg393.And 
> you may find that the receiver sensitivity is closer to 0.6 uV.
> IF you insist on using the preamp, I would suggest using a decade box to 
> attenuate after the preamp.changing the attenuation periodically to get 
> it to a better level. +18dB is a little too much for any receiver.
> 
> Jason, WA1NH

[Repeater-Builder] Re: Desense on High Power Linear Repeater?

[atms169]

I was originally leaning in that direction, purchasing 2 more cans and a new 
phasing harness.  I was told to stop what I was doing and rethink by other hams.

I think you are right. I will order the new cans and make another trip to San 
Antonio to see Don.

Don, if your reading.. I'm a headin up there sometime soon!

Aaron


--- In Repeater-Builder@yahoogroups.com, "Eric Lemmon"  wrote:
>
> Aaron,
> 
> I think we've found the cause of your desense:  The TPRD-1454 duplexer,
> which has four 5" cans, is rated at 77 dB isolation, and is marginal with 20
> watts TX and RX sensitivity of 0.4 uV- which calls for at least 82 dB
> isolation.  At 100 watts, 95 dB is recommended.  While these recommended
> figures are ballpark estimates, they have been found to be quite realistic.
> 
> If you were using a tube-type PA, you might get by with your duplexer, but a
> solid-state PA needs more isolation.  At 600 kHz separation, a duplexer with
> four 8" cans or six 5" cans is the norm, and even more is better.  Even when
> tuned on a network analyzer, a TPRD-1454 duplexer seldom can reach 80 dB-
> and that is simply not enough.
> 
> 73, Eric Lemmon WB6FLY
> 
> 

[Repeater-Builder] Re: Desense on High Power Linear Repeater?

[wa1nh]

I am going to ask a question that might sound stupid but, based upon Icom's 
ignorance, I need to ask.  
Did you ever open the repeater case on the 2m repeater and replace the rg-58 
patch cables that are zip tied to each other to connect the rf modules to the 
rear of the case before adding your preamp?  Our local repeater guys had 
serious desense and ended up replacing the junk cables with rg393.And 
you may find that the receiver sensitivity is closer to 0.6 uV.
IF you insist on using the preamp, I would suggest using a decade box to 
attenuate after the preamp.changing the attenuation periodically to get it 
to a better level. +18dB is a little too much for any receiver.

Jason, WA1NH

--- In Repeater-Builder@yahoogroups.com, "atms169"  wrote:
>
> Yeah that is a good question.  All we do is test from a portable a few miles 
> from the repeater.  Low power settings on TX for the portable.
> 
> Test with the amp inline and the amp out of the equation.  I find very 
> quickly there is something wrong.
> 
> That's all I can do, I can't vary the output power.  I can also test by just 
> dropping the 25 watts to 5 watts on the repeater when a user is on the fringe 
> of the system.  If he starts to garble with his audio, I can drop the switch 
> to 5 watts and bang, he's made it in the system clear as a bell.  If I throw 
> the switch back to 25 watts, he garbles again.  
> 
> 
> 
> --- In Repeater-Builder@yahoogroups.com, Joe  wrote:
> >
> > This leads me to a question that I have had on my mind.  How are people 
> > doing desense testing with D-Star systems?  (Remember, it's digital.)
> > 
> > 73, Joe, K1ike
> > 
> > Eric Lemmon wrote:
> > > Aaron,
> > >
> > > My CommShop for Windows program suggests that about 88 dB of isolation is
> > > needed for a 20 watt repeater, assuming 0.2 uV sensitivity on the 
> > > receiver-
> > > which you didn't specify.
> >
>

RE: [Repeater-Builder] Re: Desense on High Power Linear Repeater?

[Kris Kirby]

On Wed, 20 May 2009, Eric Lemmon wrote:
> I think we've found the cause of your desense:  The TPRD-1454 
> duplexer, which has four 5" cans, is rated at 77 dB isolation, and is 
> marginal with 20 watts TX and RX sensitivity of 0.4 uV- which calls 
> for at least 82 dB isolation.  At 100 watts, 95 dB is recommended.  
> While these recommended figures are ballpark estimates, they have been 
> found to be quite realistic.
> 
> If you were using a tube-type PA, you might get by with your duplexer, 
> but a solid-state PA needs more isolation.  At 600 kHz separation, a 
> duplexer with four 8" cans or six 5" cans is the norm, and even more 
> is better.  Even when tuned on a network analyzer, a TPRD-1454 
> duplexer seldom can reach 80 dB- and that is simply not enough.

Not to mention the LMR :-p

--
Kris Kirby, KE4AHR
Disinformation Analyst

RE: [Repeater-Builder] Re: Desense on High Power Linear Repeater?

[Eric Lemmon]

Aaron,

I think we've found the cause of your desense:  The TPRD-1454 duplexer,
which has four 5" cans, is rated at 77 dB isolation, and is marginal with 20
watts TX and RX sensitivity of 0.4 uV- which calls for at least 82 dB
isolation.  At 100 watts, 95 dB is recommended.  While these recommended
figures are ballpark estimates, they have been found to be quite realistic.

If you were using a tube-type PA, you might get by with your duplexer, but a
solid-state PA needs more isolation.  At 600 kHz separation, a duplexer with
four 8" cans or six 5" cans is the norm, and even more is better.  Even when
tuned on a network analyzer, a TPRD-1454 duplexer seldom can reach 80 dB-
and that is simply not enough.

73, Eric Lemmon WB6FLY


-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of atms169
Sent: Wednesday, May 20, 2009 5:58 PM
To: Repeater-Builder@yahoogroups.com
Subject: [Repeater-Builder] Re: Desense on High Power Linear Repeater?



Sorry about that, the model number is TPRD-1454

Aaron

--- In Repeater-Builder@yahoogroups.com
 , "Eric Lemmon" 
wrote:
>
> Aaron,
> 
> You left out the crucial information: What model Telewave duplexer?
> 
> 73, Eric Lemmon WB6FLY
> 

RE: [Repeater-Builder] Re: Desense on High Power Linear Repeater?

[de W5DK]

Put your fire suit on Aaron, you actually typed LMR. Do a search here and
you will find it is known to be a problem in duplex service.

With greater losses on UHF the ranges your observations are expected. 

Don

-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of atms169
Sent: Wednesday, May 20, 2009 9:52 PM
To: Repeater-Builder@yahoogroups.com
Subject: [Repeater-Builder] Re: Desense on High Power Linear Repeater?

Hey Don, yeah good to hear ya!

Well, the system is at my house.  If I could find a tower (Trust me I have
looked around) then that would make the world of difference.

Its up on my tower about 60 feet (Both UHF and VHF).  The VHF has pretty
good coverage.  The UHF not so much, probably half of the VHF side.

Using LMR400 for both with a 7 dB vertical for the UHF and a 4.5 dB for the
VHF.




--- In Repeater-Builder@yahoogroups.com, "de W5DK"  wrote:
>
> Aaron, 
> Howdy again neighbor! Don't start spreading rumors that its flat in Texas,
> it's all downhill to the beach.on second thought it IS flat and the
> water is bad
> 
> Are these the cavities I tuned for you last fall? If so guys these are
> typical specs for 4 cans BPBR. Sorry but I couldn't find screen shots of
> when I tuned them, they were just under 80DB as I recall, and had been
> fiddled with before I corrected them.
> 
> We had a brief discussion that day Aaron, and you are going to hear
support
> of my suggestions. Location Location Location. Whether its Dstar or not,
you
> can only squeeze so much range out of a site. You are adding items on the
RX
> and TX and have exceeded the separation specs of your duplexers. You may
be
> in the same boat many people are, all the equipment and no place to go.
You
> need to acquire a better site. 
> 
> Are you running the UHF package still? And these are at the same site
right?
> Tell us the details of the antenna systems-height, feed line (type and
> length) and antennas? I'm curious of the range differences between the UHF
> and VHF after considering the differences in antenna systems.
> 
> 
>  
> 73
> Don Kirchner W5DK
>








Yahoo! Groups Links

[Repeater-Builder] Re: Desense on High Power Linear Repeater?

[atms169]

Hey Don, yeah good to hear ya!

Well, the system is at my house.  If I could find a tower (Trust me I have 
looked around) then that would make the world of difference.

Its up on my tower about 60 feet (Both UHF and VHF).  The VHF has pretty good 
coverage.  The UHF not so much, probably half of the VHF side.

Using LMR400 for both with a 7 dB vertical for the UHF and a 4.5 dB for the VHF.




--- In Repeater-Builder@yahoogroups.com, "de W5DK"  wrote:
>
> Aaron, 
> Howdy again neighbor! Don't start spreading rumors that its flat in Texas,
> it's all downhill to the beach.on second thought it IS flat and the
> water is bad
> 
> Are these the cavities I tuned for you last fall? If so guys these are
> typical specs for 4 cans BPBR. Sorry but I couldn't find screen shots of
> when I tuned them, they were just under 80DB as I recall, and had been
> fiddled with before I corrected them.
> 
> We had a brief discussion that day Aaron, and you are going to hear support
> of my suggestions. Location Location Location. Whether its Dstar or not, you
> can only squeeze so much range out of a site. You are adding items on the RX
> and TX and have exceeded the separation specs of your duplexers. You may be
> in the same boat many people are, all the equipment and no place to go. You
> need to acquire a better site. 
> 
> Are you running the UHF package still? And these are at the same site right?
> Tell us the details of the antenna systems-height, feed line (type and
> length) and antennas? I'm curious of the range differences between the UHF
> and VHF after considering the differences in antenna systems.
> 
> 
>  
> 73
> Don Kirchner W5DK
>

[Repeater-Builder] Re: Sinclair dipole array premature failure (noisy)

[Laryn Lohman]

--- In Repeater-Builder@yahoogroups.com, "NORM KNAPP"  wrote:
>
> O I C. I guess I have never seen dipole arrays in a horixontal array before. 
> I didn't know that would work.


You've seen them.  A DB420 (one example) has 8 positions vertically, each 
position has a pair of dipoles next to each other.

Laryn K8TVZ

RE: [Repeater-Builder] Re: Desense on High Power Linear Repeater?

[de W5DK]

Aaron, 
Howdy again neighbor! Don't start spreading rumors that its flat in Texas,
it's all downhill to the beach.on second thought it IS flat and the
water is bad

Are these the cavities I tuned for you last fall? If so guys these are
typical specs for 4 cans BPBR. Sorry but I couldn't find screen shots of
when I tuned them, they were just under 80DB as I recall, and had been
fiddled with before I corrected them.

We had a brief discussion that day Aaron, and you are going to hear support
of my suggestions. Location Location Location. Whether its Dstar or not, you
can only squeeze so much range out of a site. You are adding items on the RX
and TX and have exceeded the separation specs of your duplexers. You may be
in the same boat many people are, all the equipment and no place to go. You
need to acquire a better site. 

Are you running the UHF package still? And these are at the same site right?
Tell us the details of the antenna systems-height, feed line (type and
length) and antennas? I'm curious of the range differences between the UHF
and VHF after considering the differences in antenna systems.


 
73
Don Kirchner W5DK

[Repeater-Builder] Re: Desense on High Power Linear Repeater?

[atms169]

Yeah that is a good question.  All we do is test from a portable a few miles 
from the repeater.  Low power settings on TX for the portable.

Test with the amp inline and the amp out of the equation.  I find very quickly 
there is something wrong.

That's all I can do, I can't vary the output power.  I can also test by just 
dropping the 25 watts to 5 watts on the repeater when a user is on the fringe 
of the system.  If he starts to garble with his audio, I can drop the switch to 
5 watts and bang, he's made it in the system clear as a bell.  If I throw the 
switch back to 25 watts, he garbles again.  



--- In Repeater-Builder@yahoogroups.com, Joe  wrote:
>
> This leads me to a question that I have had on my mind.  How are people 
> doing desense testing with D-Star systems?  (Remember, it's digital.)
> 
> 73, Joe, K1ike
> 
> Eric Lemmon wrote:
> > Aaron,
> >
> > My CommShop for Windows program suggests that about 88 dB of isolation is
> > needed for a 20 watt repeater, assuming 0.2 uV sensitivity on the receiver-
> > which you didn't specify.
>

RE: [Repeater-Builder] Re: Desense on High Power Linear Repeater?

[Gary Schafer]

Receiver gain does not work the same as transmitter power increase. A 10 db
increase in transmitter power is not the equivalent of adding a 10 db preamp
on the receiver. It would be if your receiver was very noisy
(internally)(very poor receiver) to start with and the 10 db preamp overcame
the receiver noise by that amount. But that rarely is the case. With a good
receiver to start with you may gain only a couple of db realization on the
receiver when adding 10 db or more gain ahead of it. You may not realize any
increase in signal recovery if there is a high noise level at the site.

Also for every db of gain that you add in front of the receiver you decrease
the intermod performance of the receiver by the same amount.

73
Gary  K4FMX

> -Original Message-
> From: Repeater-Builder@yahoogroups.com [mailto:Repeater-
> buil...@yahoogroups.com] On Behalf Of Kris Kirby
> Sent: Wednesday, May 20, 2009 9:03 PM
> To: Repeater-Builder@yahoogroups.com
> Subject: Re: [Repeater-Builder] Re: Desense on High Power Linear Repeater?
> 
> On Thu, 21 May 2009, atms169 wrote:
> > Yes, 80 dB on the duplexers, 100 watts in, that's 10 dB and the preamp
> > 18 dB, so I'm losing 8 dB ??
> 
> Assuming you're not experiencing front-end overload because of your
> pre-amp.
> 
> > The sensitivity I believe is 0.4 uV Dstar system.
> >
> > I live in Texas where it's flat.  I'm adjusting my station to
> > compensate for the height value.  More power good receive.  There is a
> > 1000 foot commercial tower here which would have been perfect, but
> > they want too much to let me use it.
> 
> Yeah, they tend to charge quite a bit to get to the top of a 1kft tower.
> 
> > I had thought of adding two more cans and purchasing a new phasing
> > harness but, someone told me to stop and just add more filters.
> >
> > So I'm not sure which direction to go.
> >
> > I would like to push more power if possible.
> 
> Transmit power does not equal recieve capability. You have to think
> bi-directionally. If you have a 6dBd antenna, and a mobile has a 3dBd
> antenna (unlikely these days), then transmitting 5W is equivalent to the
> mobile transmitting 10W. However, reciever sensitivity plays an
> important part as well. If you can't hear a station who is running 50W
> into a 3dBd antenna, he likely is not in a position to hear your
> repeater at 25W into a 6dBd antenna.
> 
> Again, take out the pre-amp, insert a silver-plated teflon barrell.
> 
> --
> Kris Kirby, KE4AHR
> Disinformation Analyst
> 
> 
> 
> 
> 
> 
> Yahoo! Groups Links
> 
> 
> 

Re: [Repeater-Builder] Desense on High Power Linear Repeater?

[Joe]

This leads me to a question that I have had on my mind.  How are people 
doing desense testing with D-Star systems?  (Remember, it's digital.)

73, Joe, K1ike

Eric Lemmon wrote:
> Aaron,
>
> My CommShop for Windows program suggests that about 88 dB of isolation is
> needed for a 20 watt repeater, assuming 0.2 uV sensitivity on the receiver-
> which you didn't specify. 

Re: [Repeater-Builder] Re: Desense on High Power Linear Repeater?

[Kris Kirby]

On Thu, 21 May 2009, atms169 wrote:
> Yes, 80 dB on the duplexers, 100 watts in, that's 10 dB and the preamp 
> 18 dB, so I'm losing 8 dB ??

Assuming you're not experiencing front-end overload because of your 
pre-amp. 
 
> The sensitivity I believe is 0.4 uV Dstar system.  
> 
> I live in Texas where it's flat.  I'm adjusting my station to 
> compensate for the height value.  More power good receive.  There is a 
> 1000 foot commercial tower here which would have been perfect, but 
> they want too much to let me use it.

Yeah, they tend to charge quite a bit to get to the top of a 1kft tower.
 
> I had thought of adding two more cans and purchasing a new phasing 
> harness but, someone told me to stop and just add more filters.
> 
> So I'm not sure which direction to go.  
> 
> I would like to push more power if possible.

Transmit power does not equal recieve capability. You have to think 
bi-directionally. If you have a 6dBd antenna, and a mobile has a 3dBd 
antenna (unlikely these days), then transmitting 5W is equivalent to the 
mobile transmitting 10W. However, reciever sensitivity plays an 
important part as well. If you can't hear a station who is running 50W 
into a 3dBd antenna, he likely is not in a position to hear your 
repeater at 25W into a 6dBd antenna. 

Again, take out the pre-amp, insert a silver-plated teflon barrell.

--
Kris Kirby, KE4AHR
Disinformation Analyst

[Repeater-Builder] OT - Tower Photographs needed

[rahwayflynn]

Anyone with a 500+ guyed tower?I am working on a power point presentation 
for the local OEM.  The subject matter is selecting an appropriate LZ for 
medivac helicopters, IE keep the aircraft away from towers and power lines.

What I am looking for is a night & day shot from exactly the same perspective 
(let the ground crew see the guys in the daylight & watch them disappear at 
night)

[Repeater-Builder] Re: Desense on High Power Linear Repeater?

[atms169]

Sorry about that, the model number is TPRD-1454

Aaron

--- In Repeater-Builder@yahoogroups.com, "Eric Lemmon"  wrote:
>
> Aaron,
> 
> You left out the crucial information:  What model Telewave duplexer?
> 
> 73, Eric Lemmon WB6FLY
>  

Re: [Repeater-Builder] Re: Sinclair dipole array premature failure (noisy)

[Chuck Kelsey]

Very common for UHF. Not seen as often on VHF. Google some of the antenna 
manufacturers or Tessco and look around.

Chuck
WB2EDV


- Original Message - 
From: "NORM KNAPP" 
To: 
Sent: Wednesday, May 20, 2009 8:50 PM
Subject: Re: [Repeater-Builder] Re: Sinclair dipole array premature failure 
(noisy)


>O I C. I guess I have never seen dipole arrays in a horixontal array 
>before. I didn't know that would work.
>
> 

Re: [Repeater-Builder] Re: Desense on High Power Linear Repeater?

[NORM KNAPP]

He may need to find a set of sinclair Q202's to go with that. I have had a bit 
of trouble with Telewave running a 100watts with only .6 mhz sep. They do fine 
at 50watts or so. Tuning gets very tricky with the TPRD-1554 cans at that much 
power and only .6 meg spread.

- Original Message -
From: Repeater-Builder@yahoogroups.com 
To: Repeater-Builder@yahoogroups.com 
Sent: Wed May 20 19:33:36 2009
Subject: RE: [Repeater-Builder] Re: Desense on High Power Linear Repeater?



Aaron,

You left out the crucial information: What model Telewave duplexer?

73, Eric Lemmon WB6FLY


-Original Message-
From: Repeater-Builder@yahoogroups.com 
 
[mailto:Repeater-Builder@yahoogroups.com 
 ] On Behalf Of atms169
Sent: Wednesday, May 20, 2009 5:29 PM
To: Repeater-Builder@yahoogroups.com 
 
Subject: [Repeater-Builder] Re: Desense on High Power Linear Repeater?

Yes, 80 dB on the duplexers, 100 watts in, that's 10 dB and the preamp 18
dB, so I'm losing 8 dB ??

The sensitivity I believe is 0.4 uV Dstar system. 

I live in Texas where it's flat. I'm adjusting my station to compensate for
the height value. More power good receive. There is a 1000 foot commercial
tower here which would have been perfect, but they want too much to let me
use it.

Model Numbers:
Angel Linear PreAmp 147GNT
Angel Linear Filters 2BP147N 
TE Systems 1412RAN Linear Amp
Superflex Cables
4 Can Telewave Duplxers 600 KHz split (Yes it does 600)

I had thought of adding two more cans and purchasing a new phasing harness
but, someone told me to stop and just add more filters. 

So I'm not sure which direction to go. 

I would like to push more power if possible.

Thanks

Aaron

--- In Repeater-Builder@yahoogroups.com 
 
 , "Eric Lemmon" 
wrote:
>
> Aaron,
> 
> My CommShop for Windows program suggests that about 88 dB of isolation is
> needed for a 20 watt repeater, assuming 0.2 uV sensitivity on the
receiver-
> which you didn't specify. Bumping the power to 100 watts will increase
that
> figure to about 95 dB. My gut feeling is that your duplexer is not up to
> the task.
> 
> What is the model number of your Telewave duplexer, and of your Angle
Linear
> bandpass filter? Are all of your jumpers double-shielded, with no
adapters?
> Do you have an isolator on the output jack of your TE amplifier? Have you
> verified with a spectrum analyzer that your PA output is free of spurs?
> 
> Since increasing the power output of a repeater seldom increases its
> coverage area, is it really necessary that you run 100 watts?
> 
> 73, Eric Lemmon WB6FLY
> 

RE: [Repeater-Builder] Re: Desense on High Power Linear Repeater?

[Eric Lemmon]

Aaron,

You left out the crucial information:  What model Telewave duplexer?

73, Eric Lemmon WB6FLY
 

-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of atms169
Sent: Wednesday, May 20, 2009 5:29 PM
To: Repeater-Builder@yahoogroups.com
Subject: [Repeater-Builder] Re: Desense on High Power Linear Repeater?



Yes, 80 dB on the duplexers, 100 watts in, that's 10 dB and the preamp 18
dB, so I'm losing 8 dB ??

The sensitivity I believe is 0.4 uV Dstar system. 

I live in Texas where it's flat. I'm adjusting my station to compensate for
the height value. More power good receive. There is a 1000 foot commercial
tower here which would have been perfect, but they want too much to let me
use it.

Model Numbers:
Angel Linear PreAmp 147GNT
Angel Linear Filters 2BP147N 
TE Systems 1412RAN Linear Amp
Superflex Cables
4 Can Telewave Duplxers 600 KHz split (Yes it does 600)

I had thought of adding two more cans and purchasing a new phasing harness
but, someone told me to stop and just add more filters. 

So I'm not sure which direction to go. 

I would like to push more power if possible.

Thanks

Aaron

--- In Repeater-Builder@yahoogroups.com
 , "Eric Lemmon" 
wrote:
>
> Aaron,
> 
> My CommShop for Windows program suggests that about 88 dB of isolation is
> needed for a 20 watt repeater, assuming 0.2 uV sensitivity on the
receiver-
> which you didn't specify. Bumping the power to 100 watts will increase
that
> figure to about 95 dB. My gut feeling is that your duplexer is not up to
> the task.
> 
> What is the model number of your Telewave duplexer, and of your Angle
Linear
> bandpass filter? Are all of your jumpers double-shielded, with no
adapters?
> Do you have an isolator on the output jack of your TE amplifier? Have you
> verified with a spectrum analyzer that your PA output is free of spurs?
> 
> Since increasing the power output of a repeater seldom increases its
> coverage area, is it really necessary that you run 100 watts?
> 
> 73, Eric Lemmon WB6FLY
> 

Re: [Repeater-Builder] Re: Sinclair dipole array premature failure (noisy)

[NORM KNAPP]

O I C. I guess I have never seen dipole arrays in a horixontal array before. I 
didn't know that would work.

- Original Message -
From: Repeater-Builder@yahoogroups.com 
To: Repeater-Builder@yahoogroups.com 
Sent: Wed May 20 12:29:21 2009
Subject: [Repeater-Builder] Re: Sinclair dipole array premature failure (noisy)



Note the problematic Sinclair VHF dipole arrays are/were the 
models with two Dipoles per mast position, which means each 
location on the mast has a horizontal bar with a folded dipoles 
at each end of the mast (two parallel dipoles per horizontal mast). 

The traditional in-line folded dipole arrays work muy bueno... 
(very well). Just the dual side-by-side FD arrays are the train 
wreck (in what appear to be the 4 and 8 bay assemblies). 

s. 

> "NORM KNAPP"  wrote:
>
> The db/Andrew/Comscope folded dipoles do not have this 
> problem? Why not? What is the difference?
> 73 de N5NPO
> Norm Knapp

[Repeater-Builder] Re: Desense on High Power Linear Repeater?

[atms169]

Yes, 80 dB on the duplexers, 100 watts in, that's 10 dB and the preamp 18 dB, 
so I'm losing 8 dB ??

The sensitivity I believe is 0.4 uV Dstar system.  

I live in Texas where it's flat.  I'm adjusting my station to compensate for 
the height value.  More power good receive.  There is a 1000 foot commercial 
tower here which would have been perfect, but they want too much to let me use 
it.

Model Numbers:
Angel Linear PreAmp 147GNT
Angel Linear Filters 2BP147N 
TE Systems 1412RAN Linear Amp
Superflex Cables
4 Can Telewave  Duplxers 600 KHz split (Yes it does 600)

I had thought of adding two more cans and purchasing a new phasing harness but, 
someone told me to stop and just add more filters.  

So I'm not sure which direction to go.  

I would like to push more power if possible.

Thanks

Aaron



--- In Repeater-Builder@yahoogroups.com, "Eric Lemmon"  wrote:
>
> Aaron,
> 
> My CommShop for Windows program suggests that about 88 dB of isolation is
> needed for a 20 watt repeater, assuming 0.2 uV sensitivity on the receiver-
> which you didn't specify.  Bumping the power to 100 watts will increase that
> figure to about 95 dB.  My gut feeling is that your duplexer is not up to
> the task.
> 
> What is the model number of your Telewave duplexer, and of your Angle Linear
> bandpass filter?  Are all of your jumpers double-shielded, with no adapters?
> Do you have an isolator on the output jack of your TE amplifier?  Have you
> verified with a spectrum analyzer that your PA output is free of spurs?
> 
> Since increasing the power output of a repeater seldom increases its
> coverage area, is it really necessary that you run 100 watts?
> 
> 73, Eric Lemmon WB6FLY
>  

RE: [Repeater-Builder] Desense on High Power Linear Repeater?

[Eric Lemmon]

Aaron,

My CommShop for Windows program suggests that about 88 dB of isolation is
needed for a 20 watt repeater, assuming 0.2 uV sensitivity on the receiver-
which you didn't specify.  Bumping the power to 100 watts will increase that
figure to about 95 dB.  My gut feeling is that your duplexer is not up to
the task.

What is the model number of your Telewave duplexer, and of your Angle Linear
bandpass filter?  Are all of your jumpers double-shielded, with no adapters?
Do you have an isolator on the output jack of your TE amplifier?  Have you
verified with a spectrum analyzer that your PA output is free of spurs?

Since increasing the power output of a repeater seldom increases its
coverage area, is it really necessary that you run 100 watts?

73, Eric Lemmon WB6FLY
 

-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:repeater-buil...@yahoogroups.com] On Behalf Of atms169
Sent: Wednesday, May 20, 2009 4:21 PM
To: Repeater-Builder@yahoogroups.com
Subject: [Repeater-Builder] Desense on High Power Linear Repeater?



Hello everyone,

I have an issue and I thought I would throw it out there!

I have a Dstar VHF repeater system.

A 4 Can Telewave Duplexer
A Chip Angle Band Pass Filter on receive
and a Chip Angle 18 dB pre-amp.

Everything works just fine running the repeater barefoot at 20 watts. My
problem is when I add the TE Systems amp (Around 100 watts out when hooked
up), I lose the sensitivity on the receive. Our portables basically get the
bad end of it.

How do I go about fixing this issue so I can have the best of both worlds? I
good receive and transmit?

Aaron
KE5KAF

Re: [Repeater-Builder] Desence on High Power Linear Repeater?

[Kris Kirby]

On Wed, 20 May 2009, atms169 wrote:
> A 4 Can Telewave Duplexer A Chip Angle Band Pass Filter on receive and 
> a Chip Angle 18db pre-amp.
> 
> Everything works just fine running the repeater barefoot at 20 watts.  
> My problem is when I add the TE Systems amp (Around 100 watts out when 
> hooked up), I lose the sensitivity on the receive.  Our portables 
> basically get the bad end of it.
> 
> How do I go about fixing this issue so I can have the best of both 
> worlds?  I good receive and transmit?

Throw out the preamp. If you still experience desense, re-engineer the 
duplexing system for higher values of seperation (in dB). The last step 
_might_ be to go to a tube final amplifier, but it should be bulletproof 
at 100W solid state first.

--
Kris Kirby, KE4AHR
Disinformation Analyst

[Repeater-Builder] Desence on High Power Linear Repeater?

[atms169]

Hello everyone,

I have an issue and I thought I would throw it out there!

I have a Dstar VHF repeater system.

A 4 Can Telewave Duplexer
A Chip Angle Band Pass Filter on receive
and a Chip Angle 18db pre-amp.

Everything works just fine running the repeater barefoot at 20 watts.  My 
problem is when I add the TE Systems amp (Around 100 watts out when hooked up), 
I lose the sensitivity on the receive.  Our portables basically get the bad end 
of it.

How do I go about fixing this issue so I can have the best of both worlds?  I 
good receive and transmit?

Aaron
KE5KAF

Re: [Repeater-Builder] Help with power supply

[Ralph Mowery]

--- On Wed, 5/20/09, Charles Lowery  wrote:

> From: Charles Lowery 
> Subject: [Repeater-Builder] Help with power supply
> To: Repeater-Builder@yahoogroups.com
> Date: Wednesday, May 20, 2009, 1:27 PM
> I purchased a Uniden 28 volt power
> supply today on ebay. It lookes like the Astron LSRM-25A or
> 35A both front and back (I assume Astron made it). With out
> seeing it I assume it works OK (cost $2.00 + shipping). Has
> anyone converted one of these to 12 volts? I have no
> schematics for it and can not find one on the net. If
> converted what would be the available current?
> 
> Charles, NM4V
> 
> 
It is usually easy to make a 28 volt suply put out 12 volts if it has the 723 
voltage regulator in it.  The problem is unless you can change the transformer 
wiring or whole transformer to put out about half the origional voltage you can 
only draw about 1/4 the origional current and even at that it will not be very 
efficiant.  You want to put about 3 to 5 volts more into the pass transistors 
than the output voltage.  If you just adjust the resistor values the 
transistors will have to dissiapate much more heat.  

Thank of it as you orgionally will have about 32 to 36 volts going to the 
transistors.  That is 4 to 8 volts you have to drop.  At 10 amps this is 40 to 
80 watts.  If you do not lower this voltage and go to 12 volts output then you 
dissipate about 200 to 240 watts.  This will probably be much more than the 
transistor/heatsink combination can dissipate.



  

Re: [Repeater-Builder] MSR 2000 simplex base station conversion to repeater

[George Henry]

I'll ftp it from home tonight  AT&T/Yahoo won't allow attachments over 5 MB.

George




From: Mike Morris WA6ILQ 
To: Repeater-Builder@yahoogroups.com
Sent: Wednesday, May 20, 2009 1:08:24 AM
Subject: Re: [Repeater-Builder] MSR 2000 simplex base station conversion to 
repeater





At 08:39 PM 05/19/09, you wrote:
>I have the -B version of the VHF manual already scanned, but it's 44
>megs.
>
>
>George, KA3HSW / WQGJ413

If your email system can send it without complaining
please send a copy to wa6...@repeater- builder.com, or you
can FTP it to ftp.repeater- builder.com - just send me an
email if you do, as we don't get an alert.

Mike WA6ILQ

Re: [Repeater-Builder] Re: Sinclair dipole array premature failure (noisy)

[Paul Kelley N1BUG]

Skipp,

Do you have any idea WHY the models with two dipoles side-by-side 
are problematic and the in-line models are not? Are there 
differences in the construction of the individual dipoles that cause 
problems? Differences in the phasing harness? I'm thinking about 
using these dipoles to build an in-line 4 bay array with my own 
harness, but if the dipoles themselves are prone to problems that 
would seem a waste of more time and money. I was considering doing 
that even before the array became a noise nightmare, since it would 
produce a pattern somewhat more to my liking and maybe (depending on 
how it was done) reduce weight and wind load.

When (if?) I recover from blood loss to black flies at the repeater 
site today, I will report on my findings testing individual dipoles 
from the problematic array

Paul N1BUG


skipp025 wrote:
> Note the problematic Sinclair VHF dipole arrays are/were the 
> models with two Dipoles per mast position, which means each 
> location on the mast has a horizontal bar with a folded dipoles 
> at each end of the mast (two parallel dipoles per horizontal mast). 
> 
> The traditional in-line folded dipole arrays work muy bueno... 
> (very well). Just the dual side-by-side FD arrays are the train 
> wreck (in what appear to be the 4 and 8 bay assemblies). 

Re: [Repeater-Builder] Radio rack mounts

[jazz101]

Sorry about the misspell of MaxTrac, I know better.

The rack mounts we produce are standard EIA 19" wide and 3.5" high with 
standard mounting slots for mounting. Supplied with 10-32 mounting hardware. 

We also offer a single version of the Maxtrac size radio cutouts.

We are also do some custom rack mount for other radios like the Kenwood 8180 
plus many of the ham HF and desk top VHF/UHF radios.

Thanks for your interest.

73's and Thanks
Dick K4EIH/6
San Diego, CA
jazz...@san.rr.com
  - Original Message - 
  From: motarolla_doctor 
  To: Repeater-Builder@yahoogroups.com 
  Sent: Tuesday, May 19, 2009 4:20 PM
  Subject: [Repeater-Builder] Radio rack mounts





  Dick, you misspelled MAXTRAC. 

  Are these for station racks, 19" racks? Mobile console rack?

  Dick K4EIH/6 San Diego, CA wrote:

  I sell Motorola Dual Maxtrec radio size (2.04x7.04 inch) rack mounts, and 
just introduce our CDM 1250/1550 Dual rack mount.




  

[Repeater-Builder] Re: Sinclair dipole array premature failure (noisy)

[skipp025]

Note the problematic Sinclair VHF dipole arrays are/were the 
models with two Dipoles per mast position, which means each 
location on the mast has a horizontal bar with a folded dipoles 
at each end of the mast (two parallel dipoles per horizontal mast). 

The traditional in-line folded dipole arrays work muy bueno... 
(very well). Just the dual side-by-side FD arrays are the train 
wreck (in what appear to be the 4 and 8 bay assemblies). 

s. 

> "NORM KNAPP"  wrote:
>
> The db/Andrew/Comscope folded dipoles do not have this 
> problem? Why not? What is the difference?
> 73 de N5NPO
> Norm Knapp

[Repeater-Builder] Help with power supply

[Charles Lowery]

I purchased a Uniden 28 volt power supply today on ebay. It lookes like the 
Astron LSRM-25A or 35A both front and back (I assume Astron made it). With out 
seeing it I assume it works OK (cost $2.00 + shipping). Has anyone converted 
one of these to 12 volts? I have no schematics for it and can not find one on 
the net. If converted what would be the available current?

Charles, NM4V

Re: [Repeater-Builder] Re: Sinclair dipole array premature failure (noisy)

[Roger Stacey]

NORM KNAPP wrote:


The db/Andrew/Comscope folded dipoles do not have this problem? Why not? What 
is the difference?
73 de N5NPO
Norm Knapp

- Original Message -
From: Repeater-Builder@yahoogroups.com 
To: Repeater-Builder@yahoogroups.com 
Sent: Wed May 20 11:11:06 2009
Subject: [Repeater-Builder] Re: Sinclair dipole array premature failure (noisy)



Should be in the group archives a few years back. 

Sinclair renamed/changed the names/model numbers for 
pretty much the exact same vhf antennas I have had all 
the hell with... but they are pretty much the same design 
as the current models with reported changes in the coax 
harness/feed system to address the IMD/PIM problem. 

I've spoken to former Sinclair Engineers in person more 
than once... got a lot of smoke blown up my back side 
but no resolution/solution to the antenna models I still 
have in storage. I know of one state agency still using 
the problematic VHF dipole assemblies and still experiencing 
grief they don't acknowledge or seem to want to properly 
deal with. Go figure... 

The IMD/PIM generation happens/happened in that series 4 
and 8 bay (two horizontal spaced dipoles per mast position) 
folded dipole antenna models. A Sinclair Engineer 
in a face to face conversation suggested I re-install my 4 
bay antennas using the information from their current (same) 
product (with a different model number). No cigar... 

No fun... lots of money and time wasted. 


s.

 


"Chuck Kelsey"  wrote:
Boy, for some reason, there's a discussion I don't 
recall. Oh well.


The only array from Sinclair I was aware of as being 
trouble was their SRL222/SD222 series.


Chuck
WB2EDV


- Original Message - 
From: "skipp025" 

To: mailto:Repeater-Builder%40yahoogroups.com> 
>
Sent: Tuesday, May 19, 2009 7:01 PM
Subject: [Repeater-Builder] Re: Sinclair dipole array premature failure 
(noisy)



   


There are known problems with this series of antennas... see
my previous posts bad-mouthing Sinclair regarding this same
situation.


 












Yahoo! Groups Links




 

We have had several failures with 2 Siclair 219 C4-2 antennas and 1 
Sinclair 229 (which was replaced by Sinclair after warantee). Symtoms 
were very bad dioding and reduced  receiver sensitivity. As these 
antennas are $1200 and $1800 for 1/2 wave spaced 4 pole up here. We did 
not want a repeat of the problems. Our solution was to use Comprod 
antennas which have performed flawlessly.


Roger
VA7RS

Re: [Repeater-Builder] Re: Sinclair dipole array premature failure (noisy)

[NORM KNAPP]

The db/Andrew/Comscope folded dipoles do not have this problem? Why not? What 
is the difference?
73 de N5NPO
Norm Knapp

- Original Message -
From: Repeater-Builder@yahoogroups.com 
To: Repeater-Builder@yahoogroups.com 
Sent: Wed May 20 11:11:06 2009
Subject: [Repeater-Builder] Re: Sinclair dipole array premature failure (noisy)



Should be in the group archives a few years back. 

Sinclair renamed/changed the names/model numbers for 
pretty much the exact same vhf antennas I have had all 
the hell with... but they are pretty much the same design 
as the current models with reported changes in the coax 
harness/feed system to address the IMD/PIM problem. 

I've spoken to former Sinclair Engineers in person more 
than once... got a lot of smoke blown up my back side 
but no resolution/solution to the antenna models I still 
have in storage. I know of one state agency still using 
the problematic VHF dipole assemblies and still experiencing 
grief they don't acknowledge or seem to want to properly 
deal with. Go figure... 

The IMD/PIM generation happens/happened in that series 4 
and 8 bay (two horizontal spaced dipoles per mast position) 
folded dipole antenna models. A Sinclair Engineer 
in a face to face conversation suggested I re-install my 4 
bay antennas using the information from their current (same) 
product (with a different model number). No cigar... 

No fun... lots of money and time wasted. 

s.

> "Chuck Kelsey"  wrote:
> Boy, for some reason, there's a discussion I don't 
> recall. Oh well.
> 
> The only array from Sinclair I was aware of as being 
> trouble was their SRL222/SD222 series.
> 
> Chuck
> WB2EDV
> 
> 
> - Original Message - 
> From: "skipp025" 
> To:   >
> Sent: Tuesday, May 19, 2009 7:01 PM
> Subject: [Repeater-Builder] Re: Sinclair dipole array premature failure 
> (noisy)
> 
> 
> > There are known problems with this series of antennas... see
> > my previous posts bad-mouthing Sinclair regarding this same
> > situation.
> >
> >
>

[Repeater-Builder] Re: Sinclair dipole array premature failure (noisy)

[skipp025]

Should be in the group archives a few years back. 

Sinclair renamed/changed the names/model numbers for 
pretty much the exact same vhf antennas I have had all 
the hell with... but they are pretty much the same design 
as the current models with reported changes in the coax 
harness/feed system to address the IMD/PIM problem. 

I've spoken to former Sinclair Engineers in person more 
than once... got a lot of smoke blown up my back side 
but no resolution/solution to the antenna models I still 
have in storage. I know of one state agency still using 
the problematic VHF dipole assemblies and still experiencing 
grief they don't acknowledge or seem to want to properly 
deal with. Go figure... 

The IMD/PIM generation happens/happened in that series 4 
and 8 bay (two horizontal spaced dipoles per mast position) 
folded dipole antenna models. A Sinclair Engineer 
in a face to face conversation suggested I re-install my 4 
bay antennas using the information from their current (same) 
product (with a different model number). No cigar... 



No fun... lots of money and time wasted. 

s.

> "Chuck Kelsey"  wrote:
> Boy, for some reason, there's a discussion I don't 
> recall. Oh well.
> 
> The only array from Sinclair I was aware of as being 
> trouble was their SRL222/SD222 series.
> 
> Chuck
> WB2EDV
> 
> 
> - Original Message - 
> From: "skipp025" 
> To: 
> Sent: Tuesday, May 19, 2009 7:01 PM
> Subject: [Repeater-Builder] Re: Sinclair dipole array premature failure 
> (noisy)
> 
> 
> > There are known problems with this series of antennas... see
> > my previous posts bad-mouthing Sinclair regarding this same
> > situation.
> >
> >
>

[Repeater-Builder] Re: MSR 2000 simplex base station conversion to repeater

[skipp025]

Hi Andy, 

You should have the duplex back plane unit (the card cage) as 
easily defined having the R1-Audio Card horizontal above the 
station control module. If the unit has CTCSS (PL) there will 
be a PL Module horizontal above and on the left side. 

It is possible to duplex a "base station" chassis, but the mod 
is not super easy or for the faint of heart. The base station 
msr-2000 back-plane does not have the row of three card slots 
sitting above the main vertical module card slots (positions).

In duplex operation you should have the Station Control Module, 
a time out timer (not really required but should be), a Squelch 
Gate Module, R1-Audio and PL Module (if you're going to run 
CTCSS). There are minor variants and subs to the above list. 

s. 


> "Andy Carstarphen"  wrote:
>
> I have an MSR2000 half-duplex base station that was removed from railroad 
> service (161 MHz). I would like to convert it to a repeater for one of our 
> local volunteer fire departments. Does anyone have a list of boards required 
> to make the station act as a full duplex repeater. The output will be in the 
> 154.145 MHz and the input will be 155.205.
> 
> Thanks,
> 
> Andy Carstarphen - WY5V
>