[Repeater-Builder] Re: WANTED: Circulator / Isolator for 146 MHz

[Al Wolfe]

Royce,
I have found a few hi-band circulators on ebay. Most there are for 
microwave but once in a while the lower frequencies ones show up.

I've also found some at hamfests. Picked up one at Dayton this year for 
440.

Some are fairly broad banded and some are very narrow. Some have tuning 
adjustments and some are fixed tuned.

All are harmonic generators and must be followed by some kind of 
low-pass filter.

Don't think I ever paid more than $30 for one.

Have patience. There are some out there.

73,
AL, K9SI



WANTED: Circulator / Isolator for 146 MHz
Posted by: "R. Crocker" [EMAIL PROTECTED] rfcrocker
Date: Wed Jul 9, 2008 9:38 am ((PDT))

Anyone have a 146 MHz circulator/isolator for sale that will handle 70w?
Please respond off list.
Royce - W3IF
 

[Repeater-Builder] Re: New Repeater Desense Problems

[Laryn Lohman]

-- In Repeater-Builder@yahoogroups.com, Nate Duehr <[EMAIL PROTECTED]> wrote:

> I wouldn't call GE's instructions on how to align them "tricky" at all.
> 
> But there's been debates here in the past as to whether or not GE's 
> instructions would REALLY be setting the correct match (since you're 
> just tuning for a voltage at a test point).

> Nate WY0X

Nate, I wonder how much current your amps are drawing...  Do you know?

IF the adjustments in a GE amp are actually Z matchers, and I believe
they are, then I believe the GE instructions are wrong.

A Z matcher's purpose is basically to maximize the efficiency of the
amplifier.  So with our repeater transmitter (VHF), which is two amps
rated at 225 watts when combined, I adjusted them for minimum current
draw at max power out.  As you adjust, you'll soon find combinations
that substantially reduce the current draw with no loss in power out.

I've also added fans to the heatsinks and to the component side of all
(3) amps in this transmitter.  Power out is set to 180 watts and so
far, zero trouble in 7 years.  I admit that my experience with these
amps is much more limited than yours, Nate, so my  may catch up
some day.

Laryn K8TVZ  

[Repeater-Builder] Re: Micor test set question

[georgiaskywarn]

Ok on both from both Kevin's.

Do have a preamp in line.  Will try it out.

Now...can the test set not be used as a "scale" with a weak signal to
"touch up" the rx side of the dup.s?  Not wanting to mess with the
front end of the receiver.  Are you also saying I should see something
on meter setting 4+?

Is "tweaking" the cans not possible with the test set?  
Robert 
KD4YDC

RE: [Repeater-Builder] Measuring Desense

[Eric Lemmon]

John,

These articles should answer any questions you might have:







Measuring effective sensitivity and the degree of desense is best done with
a service monitor, but useful measurements can be made with a calibrated
signal generator and a spectrum analyzer.  It is important to determine
whether the desense is caused by your repeater's transmitter or by another
transmitter.  The corrective actions differ, depending upon the source.

The original article in MRT (Mobile Radio Technology) Magazine included some
great step-by-step photos showing how to build an ISO-TEE, but the online
version of that article (above) omitted the photos. :-(

73, Eric Lemmon WB6FLY
  

-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of John Transue
Sent: Wednesday, July 09, 2008 12:18 PM
To: Repeater-Builder@yahoogroups.com
Subject: [Repeater-Builder] Measuring Desense

<<...>> Ron, Don, Mark, and others, 

The attachment shows how I think I should connect things to measure desense.
I would use the Bird with sampling coupler in place of the iso tee shown.
Does this appear to be a correct way to measure desense? 

Also, I can replace the feed line and antenna with a dummy load as Ron has
explained. 

John AF4PD

[Repeater-Builder] Standard Corp., Model # RP-71K

[kb5vjy]

Howdy All!!!

Has anyone converted a Standard Corp., Model # RP-71K for 900mhz? 
Just wondering.


73 de Joe KB5VJY

[Repeater-Builder] IFR A-7550 spectrum analyzer, power supply problem

[Joe]

Hello to all,

I recently acquired an IFR A-7550 and started to test it out this
afternoon.  I removed the battery from the unit because it was dead
and I didn't want to damage the power supply.  I plugged it in and
heard a squealing noise for a second or two before the fuse blew.  Any
words of advice before I start digging into the power supply of this
beast?  

73, Joe, K1ike

Re: [Repeater-Builder] Re: Selectone ST-104 Help

[Gmail - Kevin, Natalia, Stacey & Rochelle]

Hi All,

I feel like a complete idiot, I was using my Kenwood TH-78A HH with the tone on 
and wondering why I could not get a trigger from the ST-104 CTCSS board.
I then had a thought and used my TM-D700A and then it worked, triggered when 
there was a valid CTCSS tone. I can now guess my HH does not produce a CTCSS 
tone when the tone button is activated.
So now I have the Repeater RX triggering as it;'s required to do.
Sorry for the question about 30mins ago.

Regards

Kevin.
 
Get Skype and call me for free.

 
 

sparc_nz
Description: Binary data

Re: [Repeater-Builder] Re: Selectone ST-104 Help

[Gmail - Kevin, Natalia, Stacey & Rochelle]

Laryn and Others,

First of all thank you for your information, I have used this to install the 
modules.
BUT (yes there is a but) the things don't trigger. I do have the information 
sheet already downloaded from Repeater-Builder.

I fitted a pull-up resister to the decode- line and have 8v on the line, but 
when I TX the tone from my HH I get no triggering, it stays at 8v.
I have set the ST-104 to the required freq using a spec-an from work and it was 
set on the req frq I want, within a couple of Hz.

I am now looking at what other possible issues might be causing it not to 
switch.

Thanks

Kevin.

 
Get Skype and call me for free.


  - Original Message - 
  From: Laryn Lohman 
  To: Repeater-Builder@yahoogroups.com 
  Sent: Friday, May 23, 2008 2:48 PM
  Subject: [Repeater-Builder] Re: Selectone ST-104 Help


  --- In Repeater-Builder@yahoogroups.com, "Gmail - Home" <[EMAIL PROTECTED]>
  wrote:
  >

  > Can someone please guide me in what connection I should have?

  I assume you are feeding the unit with audio directly from the
  discriminator, right? 

  How are you checking for decode. If using the Decode- output, for
  example, you will need a pullup resistor because it is an open
  collector output. 

  I don't have a working unit handy so I can't answer your other
  questions right now, but check on those things first, and I or others
  will guide you deeper.

  Laryn K8TVZ



   

sparc_nz
Description: Binary data

Re: [Repeater-Builder] Re: New Repeater Desense Problems

[Nate Duehr]

wd8chl wrote:
> Laryn Lohman wrote:
>> --- In Repeater-Builder@yahoogroups.com, wd8chl <[EMAIL PROTECTED]> wrote:
>>
>>> It sounds to me like the PA wasn't aligned properly. Or the duplexer is 
>>> not aligned properly. Most, but not all, MastrII PA's have an output 
>>> filter section that is tricky to align correctly.
>> Are you referring to the Z matching adjustments on continuous-duty amps?
>>
>> Laryn K8TVZ
> 
> Yeah.

I wouldn't call GE's instructions on how to align them "tricky" at all.

But there's been debates here in the past as to whether or not GE's 
instructions would REALLY be setting the correct match (since you're 
just tuning for a voltage at a test point).

Nate WY0X

[Repeater-Builder] Looking: VHF MSR2000 Or MASTRII

[Alexander N Tubonjic]

  Looking to upgrade to a VHF (2 meter) Motorola MSR2000 or a GE MASTR
II station. Would prefer something in the West Central Florida area as
to save on shipping. Let me know the specs/condition of your equipment
and price. Thanks

 

RE: [Repeater-Builder] Measuring Desense

[John Transue]

Okay. I'll do it. Thanks.

 

John

AF4PD

 

 

-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of de W5DK
Sent: Wednesday, July 09, 2008 4:06 PM
To: Repeater-Builder@yahoogroups.com
Subject: RE: [Repeater-Builder] Measuring Desense

 

Perfect! except you want the antenna as high as possible! Hi

73

Don

W5DK

 

From: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of John Transue
Sent: Wednesday, July 09, 2008 2:18 PM
To: Repeater-Builder@yahoogroups.com
Subject: [Repeater-Builder] Measuring Desense

 

<<...>> Ron, Don, Mark, and others, 

The attachment shows how I think I should connect things to measure
desense. I would use the Bird with sampling coupler in place of the iso
tee shown. Does this appear to be a correct way to measure desense? 

Also, I can replace the feed line and antenna with a dummy load as Ron
has explained. 

John AF4PD  

 

__ NOD32 3192 (20080616) Information __

This message was checked by NOD32 antivirus system.
http://www.eset.com

Re: [Repeater-Builder] Micor test set question

[Kevin Custer]

georgiaskywarn wrote:
> I am wanting to meter the signal level on my Micor.  (to be able to
> squeeze every drop out the the rx cans)  The test set number is
> TLN1857A and TLN5900A.  From what I thought was the correct setting
> (in position 6 (if you include the -4 and +4 as 2) or set on the
> number 5) and show no change in the metering when a weaker signal
> comes in.  It pretty much stays on about 44uA.


Just guessing You're running a preamp...  If so, go around it for 
your testing as the limiter is swamped.

Kevin Custer

[Repeater-Builder] Micor test set question

[georgiaskywarn]

I am wanting to meter the signal level on my Micor.  (to be able to
squeeze every drop out the the rx cans)  The test set number is
TLN1857A and TLN5900A.  From what I thought was the correct setting
(in position 6 (if you include the -4 and +4 as 2) or set on the
number 5) and show no change in the metering when a weaker signal
comes in.  It pretty much stays on about 44uA.
Ideas?
Thanks,
Robert
KD4YDC

RE: [Repeater-Builder] Measuring Desense

[de W5DK]

Perfect! except you want the antenna as high as possible! Hi

73

Don

W5DK

 

From: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of John Transue
Sent: Wednesday, July 09, 2008 2:18 PM
To: Repeater-Builder@yahoogroups.com
Subject: [Repeater-Builder] Measuring Desense

 

<<...>> Ron, Don, Mark, and others, 

The attachment shows how I think I should connect things to measure desense.
I would use the Bird with sampling coupler in place of the iso tee shown.
Does this appear to be a correct way to measure desense? 

Also, I can replace the feed line and antenna with a dummy load as Ron has
explained. 

John AF4PD  

 

Re: [Repeater-Builder] COR REVERSE SENSE

[Ron Wright]

Chris,

Bob tried with a diagram and it did not come thru.  Another reply gave 
excellent web site for simple transistor circuits.

I'll try:

Using an NPN such as 2N3904 or 2N
1. ground emitter
2. from collector connect 4.7k res to +voltage (5, 12, etc)
3. connect 20k res to base and other end of 20k use as COR/COS input.

The inverted output will be off the collector where the 4.7k and collector 
connect.

73, ron, n9ee/r



>From: chris_campton <[EMAIL PROTECTED]>
>Date: 2008/07/09 Wed AM 10:04:09 EDT
>To: Repeater-Builder@yahoogroups.com
>Subject: [Repeater-Builder] COR REVERSE SENSE

>
>Anyone have a circuit diagram to reverse a cor from high to low to low 
>to high?
>
>   
> 


Ron Wright, N9EE
727-376-6575
MICRO COMPUTER CONCEPTS
Owner 146.64 repeater Tampa Bay, FL
No tone, all are welcome.

Re: Re: [Repeater-Builder] COR REVERSE SENSE

[Ron Wright]

Bob,

You found out as I have that yahoo takes lots out like spaces and messes things 
up.  Guess the price we have to pay for a free service.  

I once did a antenna tuner doc to show what happens to the power based on 
feedline losses, but yahoo took out the spaces and trashed it to the point I 
had trouble deciphering it.

Making a hand drawn diagram and scanning is good, but cannot send attachments 
thru the board.  Have to send directly.

73, ron, n9ee/r



>From: [EMAIL PROTECTED]
>Date: 2008/07/09 Wed AM 11:54:56 EDT
>To: Repeater-Builder@yahoogroups.com
>Subject: Re: [Repeater-Builder] COR REVERSE SENSE

>
>First try at ASCII graphics didn't look so good; trying again:
>
>>Anyone have a circuit diagram to reverse a cor from high to low to low
>>to high?
>
>. V+
>. O
>. |
>. |
>. /
>.4.7K \
>. /
>. |O OUTPUT
>. /
>.   |/
>.33K|
>.INPUT O---/\/\/\---|   2N
>.   |\
>. \
>. |
>.   -
>.---
>. -
>
>V+ can be either 5 or 12 V, depending on what output high voltage you need.
>
>Bob NO6B
>
>   
> 


Ron Wright, N9EE
727-376-6575
MICRO COMPUTER CONCEPTS
Owner 146.64 repeater Tampa Bay, FL
No tone, all are welcome.

[Repeater-Builder] Re: COR REVERSE SENSE (or lack there of...)

[skipp025]

Hi Chris, 

You can invert the COR Logic using a simple transistor or one 
section of a few different types of IC Chips. 

The "A transistor inverter (NOT gate)" portion of the following 
web page is the circuit you want. 

http://www.kpsec.freeuk.com/trancirc.htm 

The values of the resistors can be changed per the type of 
transistor you select for the task.  If you need a plane-jane 
logic inverter... higher values of resistor Rc can be used 
to reduce on-time power consumption through the resistor (Rc).
Depending on the gain (Hfe) of the transistor you will see 
values of 4.7K up through 10K often used. 

Resistor Rb value can also be changed up and down a bit... once 
again depending on the change found at the transistor collector 
when the logic on COR signal voltage is available. 

Hopefully you will see the output voltage change from something 
near the Vs (supply) value to ground (or the converse) with the 
COR potential (voltage) applied through Rb to the transistor 
base. 

If the inverter circuit loads the circuit you place the input 
onto... you can swap out the transistor to a 2N7000 (vn10) type 
fet for much less loading but a min 3vdc required to turn the 
device (fet) on. 

To prevent stray RF from causing problems... using 200pf disc 
caps at the input and output connection points will help. 

cheers,
skipp 

skipp025 at yahoo.com 

> "chris_campton" <[EMAIL PROTECTED]> wrote:
> Anyone have a circuit diagram to reverse a cor from high 
> to low to low to high?
>

[Repeater-Builder] WANTED: Circulator / Isolator for 146 MHz

[R. Crocker]

Anyone have a 146 MHz circulator/isolator for sale that will handle 70w?
Please respond off list.
Royce - W3IF

[Repeater-Builder] Re: MSR 2000

[skipp025]

Hi Dave, 

Throw the "Superior" comments out the window... both the 
MSR-2000 and Mastr II base - repeater stations are very nice 
units, quite different from each other but in many cases 
doing the same functions. 

If your MSR-2000 is the mid split version as indicated by 
your specific model number... it will tune down and operate 
well into the 2-Meter ham band without modifications. Depending 
on the specific power amplifier with your repeater/base... you 
should reduce the power output down to about 60% of normal 
operation. If you have a very busy system drop the RF Output 
level to about 45 watts and enjoy your repeater. 

If you have the high range vhf MSR-2000 Repeater the retune for 
operation into the 145 MHz Amateur Band is possible but not very 
practical. The two big issues in the way are the receiver 
pre-selector (front-end) and the rf power amplifier. I have 
converted a high split pa down using parts from a Mitrek Mobile 
for parts... but the process was very time consuming and not 
much fun. 

Ebay retail value of a VHF MSR-2000 on Ebay is about $100 to 
$350 depending on condition. Some places they're found at scrap
value and other locations they like the Mastr II can be found 
at full boat surplus retail heading well up toward the $1k price. 
Just depends on how bad you want one... 

Yep, there's a demand for them... in both Amateur and Commercial 
Applications.  

cheers,
skipp 

skipp025 at yahoo.com 


> "N0ATH" <[EMAIL PROTECTED]> wrote:
> Hello Gentlemen; 
> I recently acquired a pair of MSR 2000 100 watt
> repeaters that are on 160 mhz. I am not very well 
> acquainted with the Motorola gear although every
> one assures me they are far superior to the Mastr II 
> gear I am presently using - My question is, can the 
> 160 mhz units be moved to 146 with out a lot of 
> trouble or at all? These are operational units, one is
> new and one used - If they cannot handily be moved
> to the amateur freq then are they of very much value
> or I guess I should ask, is there any demand for them?
> Thanks / NØATH Dave
>

RE: RE: [Repeater-Builder] Re: New Repeater Desense Problems

[John Transue]

Ron N9EE

Don W5DK

Mark N9WYS

 

Thanks to all who replied. This is a big help. As it turns out, I have a
Bird meter with a model 4275-100 port. I believe this will act as an iso
tee. Am I right in believing this is the Bird way to provide for
injection or sampling?

 

John

 

-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of Ron Wright
Sent: Wednesday, July 09, 2008 10:31 AM
To: Repeater-Builder@yahoogroups.com
Subject: Re: RE: [Repeater-Builder] Re: New Repeater Desense Problems

 

John,

The tee/sampler slug is simply a loosely coupled connection to the coax
so one can insert say a generator signal into the coax without dumping
the power of the transmitter back into the signal gen.

One way to build one is to take a coaxial T connector, remove the center
pin of the vertical part (it often unscrews) of the T essentally making
it a barral connector with the vertical part of the T open except for a
few pf of capacitance between the center of the line and the vertical T
output.

One can then connect a signal gen to the vertical part of the T while it
is in the regualar coax line with power from the tx on/keyed.

To do a desense test insert the barral in the antenna line with sig gen
connected to the vertical part of the T. First with TX UNKEYED cranks up
the sig gen to get a low level say 12 db quieting with some noise at the
receiver. This level will be much higher than if connected directly to
the receiver. Then key the transmitter and see what happens to the
receiver. It will probably show some desense, but very little in a good
system. If a lot then crank up the sig gen to get the same rcvr quieting
level as without the TX and this tells you how much desense you have.

It is the same as having a weak DX station transmit to the repeater with
the TX keyed and unkeyed. However, with the sig gen you can get more of
an idea of any problem.

Also this can be done with a dummy load in the event you suspect an
antenna/feedline problem.

Any repeater will not only have desense or noise from the tepater
transmitter. It will have noise from outside sources so using this with
the antenna connected can tell you the system noise.

I did not invent it...it was around I am sure decades ago and there are
professional built units on the market. A modified T connector is just
an inexpensive way to get one.

73, ron, n9ee/r

>From: John Transue <[EMAIL PROTECTED]  net>
>Date: 2008/07/09 Wed AM 10:06:35 EDT
>To: Repeater-Builder@ 
yahoogroups.com
>Subject: RE: [Repeater-Builder] Re: New Repeater Desense Problems

> 
>
>So,please, someone tell me, what is an iso tee/sampler slug? How is the
equipmenthooked up for the desense test?
> 
>John
> 
>-Original Message-
>From:Repeater-Builder@ 
yahoogroups.com [mailto:Repeater-Builder@
 yahoogroups.com] On Behalf
Of de W5DK
>Sent: Tuesday, July 08, 2008 11:47PM
>To:Repeater-Builder@ 
yahoogroups.com
>Subject: RE: [Repeater-Builder]Re: New Repeater Desense Problems
> 
>I think he was Laryn. I could see anargument that it may not have been
aligned and caused the situation. But,,
> 
> In this case the matching circuitwas installed and set properly, also
the duplexers and all were perfect. Thesystem was stable for years then
boom, desense.
> 
>All I was saying was that this stationworked Perfect into a dummy load
(zero desense and all to spec) but did notinto feedline(+15db) . So we
cringed and focused there.
> 
>We were getting ready to replace theantenna at 580 ft and spend some
money after the dummy load test. Luckily theamp finished failing. What I
relayed locally after this experience was that acomplete system that
works flawlessly into a dummy load may not be flawless.
> 
>I do think the majority of desense problemscan be diagnosed with a
dummy load and a sampler slug / iso tee. I just wantedto throw a recent
experience / monkey wrench into the thread hi.
>73
>Don W5DK
> 
> 
> 
> 
>m: Repeater-Builder@ 
yahoogroups.com[mailto:Repeater-Builder@
 yahoogroups.com] On Behalf
Of Laryn Lohman
>Sent: Tuesday, July 08, 2008 8:50PM
>To: Repeater-Builder@ 
yahoogroups.com
>Subject: [Repeater-Builder] Re:New Repeater Desense Problems
> 
>--- In Repeater-Builder@ 
yahoogroups.com,wd8chl <[EMAIL PROTECTED]> wrote:
>
>> It sounds to me like the PA wasn't aligned properly. Or the duplexer
is 
>> not aligned properly. Most, but not all, MastrII PA's have an output 
>> filter section that is tricky to align correctly.
>
>Are you referring to the Z matching adjustments on continuous-duty
amps?
>
>Laryn K8TVZ
>
>__ NOD32 3192 (20080616) Information __
>

[Repeater-Builder] kxn-1024 conversion

[fxbuilder]

So, the kxn-1029 is hard to find. Can a 1024 be modified to be a 1029?
I've got several Micors I'd like to turn into GMRS repeaters. Any help
would be appreciated. Thanks, Craig

Re: [Repeater-Builder] New Repeater Desense Problems

[william474]

Additional accuracy can be obtained by providing a 50 ohm load for the  
generator.  This can be accomplished by connecting the center of the ISO  "T" 
to 
the center of the unmodified "T" to form an "H" configuration.  Then  connect 
the generator to one end of the unmodified "T" and a 50 ohm load to the  other 
end of the unmodified "T".  This allows the generator to "see" a 50  ohm load. 
 
billb
 
 






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**Get the scoop on last night's hottest shows and the live music 
scene in your area - Check out TourTracker.com!  
(www.tourtracker.com?NCID=aolmus0005000112)

RE: [Repeater-Builder] Re: New Repeater Desense Problems

[de W5DK]

 

 

From: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of Nate Duehr

On Jul 8, 2008, at 9:47 PM, de W5DK wrote:

> We were getting ready to replace the antenna at 580 ft and spend 
> some money after the dummy load test. Luckily the amp finished 
> failing. What I relayed locally after this experience was that a 
> complete system that works flawlessly into a dummy load may not be 
> flawless.

Don,

I think you said you looked at the PA output with a spectrum analyzer 
prior to its failure -- did you see anything?

Was your MASTR II VHF, or UHF?

 


Nate

Ours was VHF. I did look at it with my HP8921 SA, into a dummy, into the
antenna, varied the output. Over the air and through the sampler. Rechecked
the matching, bypass the isolator. I really wanted to find a problem  at the
ground level. The dynamic range of the SA will only let you see so low.

 

BTW, I only had a 30 minute driveJ

 

Parts are getting harder to find. So who has the all inclusive "instructions
and part numbers to install an RF brick into a master II station" VHF and
UHF versions of course. J

 

73

Don

 

Re: [Repeater-Builder] COR REVERSE SENSE

[no6b]

First try at ASCII graphics didn't look so good; trying again:

>Anyone have a circuit diagram to reverse a cor from high to low to low
>to high?

. V+
. O
. |
. |
. /
.4.7K \
. /
. |O OUTPUT
. /
.   |/
.33K|
.INPUT O---/\/\/\---|   2N
.   |\
. \
. |
.   -
.---
. -


V+ can be either 5 or 12 V, depending on what output high voltage you need.

Bob NO6B

Re: [Repeater-Builder] COR REVERSE SENSE

[no6b]

At 7/9/2008 07:04, you wrote:

>Anyone have a circuit diagram to reverse a cor from high to low to low
>to high?

  V+
  O
  |
  |
  /
 4.7K \
  /
  |O OUTPUT
  /
|/
 33K|
INPUT O---/\/\/\---|   2N
|\
  \
  |
-
 ---
  -


V+ can be either 5 or 12 V, depending on what output high voltage you need.

Bob NO6B

[Repeater-Builder] Re: New Repeater Desense Problems

[nj902]

Only 10 dB in SoCal?.  You're pretty lucky there Bob.  It averages 
much higher around here. It's amazing how bad this issue is.  

The major radio companies like Motorola have found this out in 
recent years.  Several large statewide VHF digital trunked systems 
have been deployed such as Virginia STARS, Wyolink and the State of 
South Dakota.  In each of these systems serious consideration had to 
be given to the degradation of system coverage that results from 
site noise.  

In TIA TSB-88-B the values given for environmental noise at VHF 
range from 11.6 to 17.7 dB above kTB depending on the location and 
LULC category [rural to major metro, tables 7&8 pg. 44&45]

--

--- In Repeater-Builder@yahoogroups.com, [EMAIL PROTECTED] wrote:

" ...except if your repeater is in SoCal, where the antenna noise 
temperature on 2 meters is about 10 dB above kTB, so throwing away a 
couple of dB between the antenna & RX isn't going to hurt you."

[Repeater-Builder] COR REVERSE SENSE

[chris_campton]

Anyone have a circuit diagram to reverse a cor from high to low to low 
to high?

Re: [Repeater-Builder] Re: MSR 2000

[Wesley Bazell]

Yep. I agree on that. Worked At motorola MSS for about 17 Years. Worked on the 
MSR2000. MastrII is Superior. My 2 Cents. wesley AB8KD
  - Original Message - 
  From: nj902 
  To: Repeater-Builder@yahoogroups.com 
  Sent: Tuesday, July 08, 2008 4:40 PM
  Subject: [Repeater-Builder] Re: MSR 2000


  MSR2000 "far superior to the Mastr II" ?

  Nah.

  I'm a Motorola kind of guy and I sure wouldn't make that statement.

  They are both capable of excellent performance so unless you need to 
  replace your Mastr II gear because of equipment failures / problems 
  you really wouldn't see any performance improvement.

  Value? Not much. MSR 2000 hasn't been made for many years. 

  Now, on the other hand, if they were MTR2000 repeaters, that would 
  be a much different situation.

  -

  --- In Repeater-Builder@yahoogroups.com, "N0ATH" <[EMAIL PROTECTED]> wrote:
  >
  > Hello Gentlemen; 
  > I recently acquired a pair of MSR 2000 100 watt
  > repeaters that are on 160 mhz. I am not very well 
  > acquainted with the Motorola gear although every
  > one assures me they are far superior to the Mastr II 
  > gear I am presently using - My question is, can the 
  > 160 mhz units be moved to 146 with out a lot of 
  > trouble or at all? These are operational units, one is
  > new and one used - If they cannot handily be moved
  > to the amateur freq then are they of very much value
  > or I guess I should ask, is there any demand for them?
  > Thanks / NØATH Dave
  >



   

[Repeater-Builder] Atten Test Meter TLN2418A Owners

[Brian Alesio]

Dear Group,

Nothing like a broken piece of test equipment.  Going to a site for 
emergency repair and finding you've got a bad test set is worse than 
being bitten by your seeing eye dog. Just passing along an experience 
related to the MSF5000 test set # TLN2418A.  I have had a test set fail 
due to secondary damage from being knocked about.  You may be able to 
save future aggravation by opening your test set and re securing the 
speaker, which is held in place by push on spring clamps and some not so 
hefty plastic pins.  In my case the speaker detached, slid over and 
contacted active electronics, which were not to happy for that 
experience.  If yours is not broken, additional insulation on the back 
of your speaker would prevent this.  If some pins are missing, some 
"Goop" or the like might be helpful to permanently hold the speaker in 
place.

BRIAN

Enter for Your Chance to WIN*
The TotalBeauty.com Summer Spa Sweepstakes!
http://thirdpartyoffers.juno.com/TGL2141/fc/JKFkuJi7UfhmKeCY5W92g6J0mpAhxGGNgaZdvTieyCVAtFPDT99W8S/--- Begin Message ---

Dear Group,

Nothing like a broken piece of test equipment.  Going to a site for 
emergency repair and finding you've got a bad test set is worse than 
being bitten by your seeing eye dog. Just passing along an experience 
related to the MSF5000 test set # TLN2418A.  I have had a test set fail 
due to secondary damage from being knocked about.  You may be able to 
save future aggravation by opening your test set and re securing the 
speaker, which is held in place by push on spring clamps and some not so 
hefty plastic pins.  In my case the speaker detached, slid over and 
contacted active electronics, which were not to happy for that 
experience.  If yours is not broken, additional insulation on the back 
of your speaker would prevent this.  If some pins are missing, some 
"Goop" or the like might be helpful to permanently hold the speaker in 
place.


BRIAN

--- End Message ---

RE: [Repeater-Builder] Re: New Repeater Desense Problems

[n9wys]

Don, that only works if he owns a Bird 43 or similar meter.  ;-)  He can
also construct one of his own from a UHF "T" connector.

 

Now, a question of my own.  Kevin (or anyone else) will this also work with
a Bird 4410 (multi-range) meter??  If so, I'll build one at my next
convenience!

 

Mark - N9WYS

 

From: Repeater-Builder@yahoogroups.com  On Behalf Of de W5DK



Using a Mike quote "doesn't anybody read the site?!!!"

http://www.repeater-builder.com/projects/bird43sampler.html

 

sorry John could resist J

 

and Ron's description / answer was correct.

73

Don W5DK

 

From: Repeater-Builder@yahoogroups.com  On Behalf Of John Transue

So, please, someone tell me, what is an iso tee/sampler slug? How is the
equipment hooked up for the desense test?

John

RE: [Repeater-Builder] New Repeater Desense Problems

[n9wys]

John,

In the cases I have seen, an "Iso-Tee" is constructed by removing the center 
pin in the offset side of a UHF "T" connector, grinding it down until it is 
flat with the insulator surface (add a notch so you can re-insert with a 
screwdriver) and reinsert the pin into the connector.  This provides for an 
indirect connection for testing purposes.

The link below describes the theory/practice behind its design and use, 
although the author uses an insulator sleeve around the center pin of his 
connector rather than the design I am familiar with.

http://www.conknet.com/~b_mobile/NoiseStuff.html 

This article describes the design I am familiar with:

http://mrtmag.com/mag/radio_rf_samplers_directional/ 

If you have a Bird wattmeter, you can construct one for use with your meter:

http://www.repeater-builder.com/projects/bird43sampler.html 

Hope this helps!
Mark - N9WYS

-Original Message-
>From: John Transue <[EMAIL PROTECTED]>
>Date: 2008/07/09 Wed AM 10:06:35 EDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: [Repeater-Builder] Re: New Repeater Desense Problems

>So, please, someone tell me, what is an iso tee/sampler slug? How is the 
>equipmenthooked up for the desense test?
> 
>John

RE: [Repeater-Builder] Re: New Repeater Desense Problems

[de W5DK]

Using a Mike quote "doesn't anybody read the site?!!!"

http://www.repeater-builder.com/projects/bird43sampler.html

 

sorry John could resist J

 

and Ron's description / answer was correct.

73

Don W5DK

 

From: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of John Transue
Sent: Wednesday, July 09, 2008 9:07 AM
To: Repeater-Builder@yahoogroups.com
Subject: RE: [Repeater-Builder] Re: New Repeater Desense Problems

 

So, please, someone tell me, what is an iso tee/sampler slug? How is the
equipment hooked up for the desense test?

 

John

 

-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of de W5DK
Sent: Tuesday, July 08, 2008 11:47 PM
To: Repeater-Builder@yahoogroups.com
Subject: RE: [Repeater-Builder] Re: New Repeater Desense Problems

 

I think he was Laryn. I could see an argument that it may not have been
aligned and caused the situation. But,,

 

 In this case the matching circuit was installed and set properly, also the
duplexers and all were perfect. The system was stable for years then boom,
desense.

 

All I was saying was that this station worked Perfect into a dummy load
(zero desense and all to spec) but did not into feedline(+15db) . So we
cringed and focused there.

 

We were getting ready to replace the antenna at 580 ft and spend some money
after the dummy load test. Luckily the amp finished failing. What I relayed
locally after this experience was that a complete system that works
flawlessly into a dummy load may not be flawless.

 

I do think the majority of desense problems can be diagnosed with a dummy
load and a sampler slug / iso tee. I just wanted to throw a recent
experience / monkey wrench into the thread hi.

73

Don W5DK

 

 

 

 

m: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of Laryn Lohman
Sent: Tuesday, July 08, 2008 8:50 PM
To: Repeater-Builder@yahoogroups.com
Subject: [Repeater-Builder] Re: New Repeater Desense Problems

 

--- In Repeater-Builder@yahoogroups.com
 , wd8chl <[EMAIL PROTECTED]> wrote:

> It sounds to me like the PA wasn't aligned properly. Or the duplexer is 
> not aligned properly. Most, but not all, MastrII PA's have an output 
> filter section that is tricky to align correctly.

Are you referring to the Z matching adjustments on continuous-duty amps?

Laryn K8TVZ


__ NOD32 3192 (20080616) Information __

This message was checked by NOD32 antivirus system.
http://www.eset.com

 

Re: RE: [Repeater-Builder] Re: New Repeater Desense Problems

[Ron Wright]

John,

The tee/sampler slug is simply a loosely coupled connection to the coax so one 
can insert say a generator signal into the coax without dumping the power of 
the transmitter back into the signal gen.

One way to build one is to take a coaxial T connector, remove the center pin of 
the vertical part (it often unscrews) of the T essentally making it a barral 
connector with the vertical part of the T open except for a few pf of 
capacitance between the center of the line and the vertical T output.

One can then connect a signal gen to the vertical part of the T while it is in 
the regualar coax line with power from the tx on/keyed.

To do a desense test insert the barral in the antenna line with sig gen 
connected to the vertical part of the T.  First with TX UNKEYED cranks up the 
sig gen to get a low level say 12 db quieting with some noise at the receiver.  
This level will be much higher than if connected directly to the receiver.  
Then key the transmitter and see what happens to the receiver.  It will 
probably show some desense, but very little in a good system.  If a lot then 
crank up the sig gen to get the same rcvr quieting level as without the TX and 
this tells you how much desense you have.

It is the same as having a weak DX station transmit to the repeater with the TX 
keyed and unkeyed.  However, with the sig gen you can get more of an idea of 
any problem.

Also this can be done with a dummy load in the event you suspect an 
antenna/feedline problem.

Any repeater will not only have desense or noise from the tepater transmitter.  
It will have noise from outside sources so using this with the antenna 
connected can tell you the system noise.

I did not invent it...it was around I am sure decades ago and there are 
professional built units on the market.  A modified T connector is just an 
inexpensive way to get one.

73, ron, n9ee/r



>From: John Transue <[EMAIL PROTECTED]>
>Date: 2008/07/09 Wed AM 10:06:35 EDT
>To: Repeater-Builder@yahoogroups.com
>Subject: RE: [Repeater-Builder] Re: New Repeater Desense Problems

>
>
>So,please, someone tell me, what is an iso tee/sampler slug? How is the 
>equipmenthooked up for the desense test?
> 
>John
> 
>-Original Message-
>From:Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of 
>de W5DK
>Sent: Tuesday, July 08, 2008 11:47PM
>To:Repeater-Builder@yahoogroups.com
>Subject: RE: [Repeater-Builder]Re: New Repeater Desense Problems
> 
>I think he was Laryn. I could see anargument that it may not have been aligned 
>and caused the situation. But,,
> 
> In this case the matching circuitwas installed and set properly, also the 
>duplexers and all were perfect. Thesystem was stable for years then boom, 
>desense.
> 
>All I was saying was that this stationworked Perfect into a dummy load (zero 
>desense and all to spec) but did notinto feedline(+15db) . So we cringed and 
>focused there.
> 
>We were getting ready to replace theantenna at 580 ft and spend some money 
>after the dummy load test. Luckily theamp finished failing. What I relayed 
>locally after this experience was that acomplete system that works flawlessly 
>into a dummy load may not be flawless.
> 
>I do think the majority of desense problemscan be diagnosed with a dummy load 
>and a sampler slug / iso tee. I just wantedto throw a recent experience / 
>monkey wrench into the thread hi.
>73
>Don W5DK
> 
> 
> 
> 
>m: [EMAIL PROTECTED]:[EMAIL PROTECTED] On Behalf Of Laryn Lohman
>Sent: Tuesday, July 08, 2008 8:50PM
>To: Repeater-Builder@yahoogroups.com
>Subject: [Repeater-Builder] Re:New Repeater Desense Problems
> 
>--- In Repeater-Builder@yahoogroups.com,wd8chl <[EMAIL PROTECTED]> wrote:
>
>> It sounds to me like the PA wasn't aligned properly. Or the duplexer is 
>> not aligned properly. Most, but not all, MastrII PA's have an output 
>> filter section that is tricky to align correctly.
>
>Are you referring to the Z matching adjustments on continuous-duty amps?
>
>Laryn K8TVZ
>
>__ NOD32 3192 (20080616) Information __
>
>This message was checked by NOD32 antivirus system.
>http://www.eset.com
>


Ron Wright, N9EE
727-376-6575
MICRO COMPUTER CONCEPTS
Owner 146.64 repeater Tampa Bay, FL
No tone, all are welcome.

RE: [Repeater-Builder] Re: New Repeater Desense Problems

[John Transue]

So, please, someone tell me, what is an iso tee/sampler slug? How is the
equipment hooked up for the desense test?

 

John

 

-Original Message-
From: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of de W5DK
Sent: Tuesday, July 08, 2008 11:47 PM
To: Repeater-Builder@yahoogroups.com
Subject: RE: [Repeater-Builder] Re: New Repeater Desense Problems

 

I think he was Laryn. I could see an argument that it may not have been
aligned and caused the situation. But,,

 

 In this case the matching circuit was installed and set properly, also
the duplexers and all were perfect. The system was stable for years then
boom, desense.

 

All I was saying was that this station worked Perfect into a dummy load
(zero desense and all to spec) but did not into feedline(+15db) . So we
cringed and focused there.

 

We were getting ready to replace the antenna at 580 ft and spend some
money after the dummy load test. Luckily the amp finished failing. What
I relayed locally after this experience was that a complete system that
works flawlessly into a dummy load may not be flawless.

 

I do think the majority of desense problems can be diagnosed with a
dummy load and a sampler slug / iso tee. I just wanted to throw a recent
experience / monkey wrench into the thread hi.

73

Don W5DK

 

 

 

 

m: Repeater-Builder@yahoogroups.com
[mailto:[EMAIL PROTECTED] On Behalf Of Laryn Lohman
Sent: Tuesday, July 08, 2008 8:50 PM
To: Repeater-Builder@yahoogroups.com
Subject: [Repeater-Builder] Re: New Repeater Desense Problems

 

--- In Repeater-Builder@ 
yahoogroups.com, wd8chl <[EMAIL PROTECTED]> wrote:

> It sounds to me like the PA wasn't aligned properly. Or the duplexer
is 
> not aligned properly. Most, but not all, MastrII PA's have an output 
> filter section that is tricky to align correctly.

Are you referring to the Z matching adjustments on continuous-duty amps?

Laryn K8TVZ

 

__ NOD32 3192 (20080616) Information __

This message was checked by NOD32 antivirus system.
http://www.eset.com

Re: [Repeater-Builder] Re: New Repeater Desense Problems

[wd8chl]

Laryn Lohman wrote:
> --- In Repeater-Builder@yahoogroups.com, wd8chl <[EMAIL PROTECTED]> wrote:
> 
>> It sounds to me like the PA wasn't aligned properly. Or the duplexer is 
>> not aligned properly. Most, but not all, MastrII PA's have an output 
>> filter section that is tricky to align correctly.
> 
> Are you referring to the Z matching adjustments on continuous-duty amps?
> 
> Laryn K8TVZ

Yeah.

Re: [Repeater-Builder] New Repeater Desense Problems

[wd8chl]

Mike Morris WA6ILQ wrote:

> And some evening spend some time reading this:
> 
> Yes, some of the info is 40 years old, but the physics of RF hasn't
> changed.
> 
> Mike WA6ILQ

And never will!
At least not until somebody figures out how sub-space communications works!
;cD

Re: [Repeater-Builder] MSF5000 Uniboard Needed

[Bob M.]

We need to know what band (VHF, UHF, 800 MHz, 896 MHz) station you have, as the 
Uniboards are quite different for the 800 and 896 MSFs.

I had a problem with those connector assemblies. Some crud on top of the 
feed-thru capacitor was acting as a semiconductor, dragging a line low and 
causing all sorts of troubles.

The connector assemblies can be unscrewed and unplugged. Scratch a locating 
mark on each one and remove one at a time. Then use an ohm-meter on every pin 
to ground and make sure you have infinite resistance (over 100 megohms). I 
measured 10-50k on one pin to ground with a digital multimeter that uses 
low-voltage on the ohms scale, but it acted like 1k to ground with 9.6V applied 
to it. Scraped the crud off the top and bottom of the feed-thru cap and the 
resistance went back to infinity. Put the cleaned connector assembly back and 
do another one. Most likely the two that connect the Uniboard to the 
Interconnect board under the RF tray are the culprits.

If pushing on the Uniboard causes the problem to go away, then you should just 
try to find the signal that's changing and fix that. Could be a cracked foil, a 
bad solder joint (most unlikely), or a loose pin in one of the Uniboard's 
sockets. Loose in this context means it got spread internally and isn't putting 
enough pressure on the gold feed-thru pin. Any repair of this type will be a 
lot cheaper than another Uniboard.

Bob M.
==
--- On Wed, 7/9/08, garyp609 <[EMAIL PROTECTED]> wrote:

> From: garyp609 <[EMAIL PROTECTED]>
> Subject: [Repeater-Builder] MSF5000 Uniboard Needed
> To: Repeater-Builder@yahoogroups.com
> Date: Wednesday, July 9, 2008, 6:18 AM
> I am looking for a uniboard that snaps into the RF deck. I
> was having a 
> problem with my repeater being off frequency on the receive
> side by 
> 6khz. Upon inspection and testing of the repeater at the
> site by 
> pressing on the uniboard the receive lines up and works
> fine. There is 
> probably a bad cap or solder joint I was told. If anyone
> knows where I 
> can get another uniboard please let me know. I was told in
> another post 
> to clean the connections between the uniboard and the RF
> deck and it 
> didn't fix the problem. I have narrowed it down to the
> uniboard so any 
> help in locating one would be apppreciated. Thanks &
> 73's
> Gary K2ACY


  

Re: [Repeater-Builder] GE Rangr problem

[Jim Brown]

Dave, Bud N0IA has been using a Rangr as a combined packet transceiver and a 
control receiver for a repeater.  Unless you are talking about the same system 
he was addressing.  Last I heard from him I thought it was working.

A suggestion - take the packet receive signal from the vol/sq HI output of the 
Rangr through a 15K series resistor with a 0.22 cap to ground.  This will 
de-emphasize the receive audio for both the TNC and control receiver input on 
the repeater controller.  You may need to add an emitter follower to the output 
to drive both loads.

Also, if you are using pin 34 on the Rangr as the CTCSS decode for the repeater 
controller be sure to 'lightly' load this pin.  It was designed as an input, 
not an output, and an emitter follower would be prudent to avoid shutting off 
the audio from the radio.

I can whip out a circuit for addressing your installation if you are 
interested.  I have been using Rangr radios as the link to EchoLink repeaters 
and as a simplex link, and have had really good results from them.

73 - Jim  W5ZIT

--- On Wed, 7/9/08, Dave <[EMAIL PROTECTED]> wrote:
From: Dave <[EMAIL PROTECTED]>
Subject: [Repeater-Builder] GE Rangr problem
To: Repeater-Builder@yahoogroups.com
Date: Wednesday, July 9, 2008, 6:45 AM











We are trying to use a UHF GE Rangr that is on packet at the 
repeater 

site as a control radio for the repeater also.

This is most baffling - having any TNC hooked up to the GE Rangr 

defeats the decoding of CTCSS used to open the port on the repeater 

controller!  I've tried two KPC-9612s (one + one old) and a PK-96,  If 

the TXA line is connected between the TNC and the radio -  no decoding 

of CTCSS.

Otherwise the Rangr works just fine as a packet radio.




  


_

 

















  

[Repeater-Builder] GE Rangr problem

[Dave]

We are trying to use a UHF GE Rangr that is on packet at the repeater 
site as a control radio for the repeater also.
This is most baffling - having any TNC hooked up to the GE Rangr 
defeats the decoding of CTCSS used to open the port on the repeater 
controller!  I've tried two KPC-9612s (one + one old) and a PK-96,  If 
the TXA line is connected between the TNC and the radio -  no decoding 
of CTCSS.
Otherwise the Rangr works just fine as a packet radio.

[Repeater-Builder] MSF5000 Uniboard Needed

[garyp609]

I am looking for a uniboard that snaps into the RF deck. I was having a 
problem with my repeater being off frequency on the receive side by 
6khz. Upon inspection and testing of the repeater at the site by 
pressing on the uniboard the receive lines up and works fine. There is 
probably a bad cap or solder joint I was told. If anyone knows where I 
can get another uniboard please let me know. I was told in another post 
to clean the connections between the uniboard and the RF deck and it 
didn't fix the problem. I have narrowed it down to the uniboard so any 
help in locating one would be apppreciated. Thanks & 73's
Gary K2ACY