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Old June 12th 05, 06:37 PM
Roger Conroy
 
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"Ed" wrote in message
. 93.175...


Mike,

Without knowing you, I have to only guess at your previous "CB"
experience, and in doing so, will guess that it is a far cry from the
knowledge and experience a good LMR technician has. Commercial radio is
not CB! Only guessing from the description of your system that you gave,
that is is poorly maintained, at best, and that the repeater had probably
been neglected for quite some time? Several hours of labor would not be
prohibitive, under those circumstances.

Assuming you can properly solder/crimp, and install RF connectors,
I'd guess that you probably can save some money by doing some of the more
basic work yourself. However, you will need more than a CB type SWR
meter. I'd suggest a Bird Model 43 with the appropriate slug for your
frequency and power. That will set you back at least $300.00+. Also,
you probably ought to purchase some good quality connectors, antennas,
and antenna cable/NMO installation kits as I expect you will find several
of the busses needing them.

Good luck trying to do it yourself.

Ed K7AAT


IMHO a Bird meter is overkill in this situation. It's a bit like
recommending
a Rolls Royce for doing the weekly shopping. It will work, but so will a VW.
There are any number of
perfectly adequate meters from a wide variety of manufacturers at prices
considerably below that of a Bird.

73
Roger ZR3RC
http://www.sarl.org.za/callresponse.asp?Callsign=ZR3RC


  #12   Report Post  
Old June 12th 05, 07:08 PM
gb
 
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----- Original Message -----
From: "Ed"
Newsgroups: rec.radio.amateur.antenna
Sent: Saturday, June 11, 2005 8:44 PM
Subject: Service Help


Thanks for the suggestions. Is $300 entry/mid for a basic meter of
this type?

Mike



I have a spare Bird 43 meter with the Peak Modification (your choice of "N"
or UHF" connectors) and the leather carrying case that I could sell you for
that price.

This came out of Cellular industry component repair shop (Condition is
virtually new - described as "very good")

You would need to purchase the appropriate Bird Element for the Frequency
and Power of the radios you use.

gb


  #13   Report Post  
Old June 12th 05, 08:42 PM
Ed
 
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IMHO a Bird meter is overkill in this situation. It's a bit like
recommending
a Rolls Royce for doing the weekly shopping. It will work, but so will
a VW. There are any number of
perfectly adequate meters from a wide variety of manufacturers at
prices considerably below that of a Bird.


I certainly don't consider a Bird watt meter to be a "Rolls Royce" in
the communications maintenance industry. If you look at ANY two-way
radio maintenance shop, you will most likely find a Bird watt meter being
used on a regular basis. Its more like a "Chevy" than a Rolls!

The guy is looking to do maintenance on a fleet of unknown number of
busses. I recommended an instrument he can trust, and that will hold up
to a considerable amount of physical abuse. So, if you think the Bird
is too much, what are your suggestions for this guy?



Ed
  #14   Report Post  
Old June 13th 05, 06:35 PM
 
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Gentlemen,

Thank you for your responses. I appreciate the assistance.

It appears that I need to provide a bit more information to give you
more insight into the circumstances I am faced with. I had hoped to
keep both the question and responses as uncomplicated as possible.
However, given the direction that a couple of responses have taken I
see the need for expanded information.

It is true that I have substantial management experience, but it lies
in a very different industry. In fact, for 11-years I owned a consumer
electronics engineering/manufacturing company with sales in many
foreign countries. During that time my company never borrowed any money
and never carried any debt. Nevertheless, the time came to close the
company and I did so. While it was not the easiest decision to make, it
was the right one and the right time to do it.

I took a job last August driving school bus for a local barn for a
large foreign-owned company, and shortly thereafter an opening for an
operations clerk (glorified secretary), became available and I took it.
(Yes, it's been humbling, but I have little room for ego.) It turns out
that not only am I new in my position (as well as to the transportation
industry), but the dispatcher and operations manager for the particular
barn I work in are new in their positions as well. That is not to say
that they are new to the company or to the industry. The operations
manager has 9-years with the company.

I believe that part of my job is to help my superiors be successful and
to look good to theirs. While I am hoping that other doors of
opportunity will open for me, I have a responsibility to be as good an
"operations clerk" as possible.

In this particular circumstance, I have come in long after the horse
has escaped, as have my two immediate superiors. The issue with the
communications amongst the 40 busses at this location is one that the
three of us are attempting to clean up.

In terms of the rate charged, our mechanic gets about $15 per hour,
while I get $9. Local auto dealers charge $45-$65 an hour. Therefore,
using this as a reference $80 just seemed a bit steep. That said, if
that is customary for UHF work then I will accept that as I said. Given
the AP that I've seen, it seems clear that there is no service contract
in place.

While the repairs made to the repeater did get channel 1 working again,
it has a high static level with most but not all busses. A couple of
busses sound relatively clear, while most others are nearly
unintelligeable. Channel 2 (direct) generally sounds much better across
the board. However, even then many of the busses have problems. This is
what leads me to suspect various antenna tuning issues. Therefore, my
question about the feasibility of doing that in-house. I would much
prefer to pay $15 an hour than $80 for the same work, but only of it
makes sense to do so.

I hope that this provides more of the information that you gentlemen
need to help me determine the most prudent course of action. I would
like to be able to make a reasonably intelligent and informed
recommendation to my superior. Thank you again for your assistance.

Mike

  #15   Report Post  
Old June 13th 05, 07:51 PM
Richard Clark
 
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On 13 Jun 2005 10:35:40 -0700, "
wrote:

While the repairs made to the repeater did get channel 1 working again,
it has a high static level with most but not all busses. A couple of
busses sound relatively clear, while most others are nearly
unintelligeable. Channel 2 (direct) generally sounds much better across
the board. However, even then many of the busses have problems. This is
what leads me to suspect various antenna tuning issues.


Hi Mike,

Your last sentence is what is called looking for your lost keys at
night, beneath the only streetlight. It's not that you lost them
there, it is simply your only working option. You may appreciate how
poor this strategy actually succeeds in the real world.

Static is not a normal indication of good operation. That much rings
true. However, tuning antennas is improvement by degree, not by leaps
and bounds - unless something very obviously wrong is quite visually
evident with the antenna. You may even have to accept the possibility
that this system never worked very well to begin with.

You say a couple of busses work well, and this in its own right tends
to remove the repeater from the list of problems - but your
description of problems is still slim. You say nothing of terrain,
service area (how many square miles, blocks, or whatever), or pattern
of coverage. Unintelligible is another fuzzy word to describe
communications. Is this because of static? distortion? other noise?
weak signal? Is this static: ignition noise? road noise? power line
noise?

FM communications rarely presents you with noise problems unless your
power level (from the repeater) is seriously low or your receiver is
seriously mistuned, or its antenna situation is seriously mangled
(have you looked?). Receivers don't get mistuned typically, and
antennas are quite robust. You already offer that point to point comm
on ch 2 is a mixed bag. Start by using what field medics call triage.
That is separate the well from the infirmed, and the dead from those
who need help.

In the end, you can spend far more at $15/hr accomplishing nearly no
good results than you would with an hour's time from a good tech.
Have you tried talking to him? I bet no more than 5 minutes of
conversation would reveal much.

73's
Richard Clark, KB7QHC


  #16   Report Post  
Old June 13th 05, 10:50 PM
gb
 
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"Richard Clark" wrote in message
...
On 13 Jun 2005 10:35:40 -0700, "
wrote:


Richard has covered many of your concerns.

In terms of the rate charged, our mechanic gets about $15 per hour, while
I get $9.


With the proper tools, replacement materials, correct knowledge and a
motivated/productive worker(s) (less than your $15/hour mechanic) - you can
improve the operation of this system.

Did you know that many stereo installation workers (e.g. Best Buy, Fry's
stereo shops) and even some LMR shops make about this same wage range?
It is usually an apprentice or entry level position for LMR shops !

So, how can you make it happen?

Richard gave an excellent FIRST step
"Start by using what field medics call triage."


My Dad and Elmer's taught me 35 years ago that you need to quickly separate
the "wheat from the chaff".
Some of your "problem radios" in buses may actually be "bad radios" AND "bad
antennas". IF a radio has a shorted coax, the final RF transistors inside
the radio may have been damaged (like running an engine with no "oil
warning" light -- damage is or has occurred and you don't know it !)
There is no easy way that you will know this without diagnostic equipment.

While the repairs made to the repeater did get channel 1 working again,
it has a high static level with most but not all busses. A couple of
busses sound relatively clear, while most others are nearly
unintelligible.


While a number of problems can cause high static levels -- I would FIRST
suspect a broken shield in the antenna coax -- due to rough "installs and
reinstalls" from buses -- so that ignition noise from the bus engine is
being picked up by the radio.

Now, you still need to have a sit down conversation (for research and
business relationship purposes) with your local LMR. The purpose of this
meeting (about 30 minutes) is to introduce yourself and come away with the
following accomplishments. Something like this:

1. Establish a business relationship with the owner or manager of this
business. Who is he/she? How long in business? Did they originally install
and design this system for the company?
You just handed him a check for services -- and he/she should be happy to do
this.

2. Outline -- at a high level -- your problem, which is:
+ Due to regular replacement of buses, your staff has to remove and
install 40 radios very 12 to 24 months.

+ You have recently joined the company and discovered that the knowledge
to do this work properly has been lost (due to employee turnover).

+ The company needs to regain sufficient knowledge to perform this work at
"odd hours" or on "short notice".

+ You would like a proposal from this LMR company:
Cost to perform this changeout service per bus (at their facility OR at
your facility - likely 2 prices here) - and any discounts for guaranteed
volume of work (per bus) for a given time period.
(This service should include assurance of both the radio and antenna)

3. Ask the company if they would be willing to have 2 of your staff members
"shadow" his install technicians. I know of many LMR that are restricted
from doing this by their business insurers (similar restrictions exist for
many insurance policies at automotive and truck garages - you may have such
a restriction at your own bus garage
Your staff likely knows "buses" better than his LMR techs - and joint
knowledge may be required for proper power routing to radio and antenna
placement on the bus. No one has mentioned this - but the placement of a
UHF antenna on a large bus is a KEY DECISION for proper operation.

AFTER, you get his written or verbal proposal, I would suggest that you
propose to your management to try this out on the 2 bus radio installs - for
you suspect that there are several issues at work in those instances.

Select the worst 2 bus radios --- preferably to be removed and installed in
2 brand new buses. This is what I refer to as a "BOOT STRAP" upgrade -
taking the worst and making it the best.
NEW BUS - GOOD RADIO, POSITIVE Driver comments about these NEW BUSES -
immediate quality improvement -- easier to continue program -- you get "buy
in".

You will likely find the following reported to you by the LMR company -- as
they have the "UHF bus radios" on the bench.

1. Bad coax that needs replacing
2. New whip required for antenna or "recutting"
3. You may require "noise suppression" on the power lead from the battery
due to engine noise (e.g. spark plug, ignition system)
4. Damage or failure of the radio -- if you have no maintenance agreement --
this is break fix at a bench rate -- the alternatives are NO RADIO, FIX
RADIO or REPLACE RADIO

Lastly, although you are upgrading and changing buses on a regular schedule
(and tires) - where is the yearly budget allocation for the communication
system? Did you know that if you handle the accounting properly -- you can
include these radios in the overall capital depreciation of the buses?
IF you did not know this (kick your accountant in the ass for me) - that is
pretty basic.

Greg
w9gb


  #17   Report Post  
Old June 15th 05, 07:33 PM
 
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Thank you again for your replies.

I agree with your assessment that much of our (company's) internal
(operational) systems may be considered "broken" by virtue of current
circumstance. Unfortunately (or perhaps fortunately depending on ones
point of view), I am not in a position to have any real effect in
matters I am not paid to have an opinion on.

However, regarding the communications amongst the 40 or so busses I can
have a positive effect on, there may be some positive contributions I
can make. I have recently learned that our mechanic has been the one to
install the radios, coax, and antennas all along.

The way the (broken) system apparently works:

Barn gets new bus in.
Manager asks for permission to buy new radio for new bus.
Uppon approval, manager orders new radio system (radio, coax, antenna,
hardware, etc.), from local company.
Mechanic installs new radio into new bus.
Everyone hopes for the best.

In the course of conversation with our mechanic this morning on the
matter, I learned that he has mounted a number of the antennas on a
part of the bus that is fiberglass. I tried to explain a bit about
ground-plane to him and the need for the antennas to be mounted on a
metal part of the bus. I' am having him take one of the "worst"
communicating busses and move the antenna to a metal part of the bus. I
am also having him go through all the contacts and connections and
cleaning them. I'll post what was done and what the results have been.

Thanks again for your help!

Mike

  #18   Report Post  
Old June 15th 05, 08:21 PM
gb
 
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" wrote in message
oups.com...
Thank you again for your replies.

I agree with your assessment that much of our (company's) internal
(operational) systems may be considered "broken" by virtue of current
circumstance. Unfortunately (or perhaps fortunately depending on ones
point of view), I am not in a position to have any real effect in
matters I am not paid to have an opinion on.

However, regarding the communications amongst the 40 or so busses I can
have a positive effect on, there may be some positive contributions I
can make. I have recently learned that our mechanic has been the one to
install the radios, coax, and antennas all along.

The way the (broken) system apparently works:

Barn gets new bus in.
Manager asks for permission to buy new radio for new bus.
Uppon approval, manager orders new radio system (radio, coax, antenna,
hardware, etc.), from local company.
Mechanic installs new radio into new bus.
Everyone hopes for the best.

In the course of conversation with our mechanic this morning on the
matter, I learned that he has mounted a number of the antennas on a
part of the bus that is fiberglass. I tried to explain a bit about
ground-plane to him and the need for the antennas to be mounted on a
metal part of the bus. I' am having him take one of the "worst"
communicating busses and move the antenna to a metal part of the bus. I
am also having him go through all the contacts and connections and
cleaning them. I'll post what was done and what the results have been.

Thanks again for your help!
Mike


Mike -

VERY USEFUL INFORMATION.

Yes, fiberglass is worthless for the required ground plane of a 1/4 wave UHF
antenna - and requires additional materials.
PCTEL based in the Chicago area is a major antenna mfg. and suppliers (e.g.
MAXRAD, Antenna Specialists).

They have 2 suitable products specifically made for fiberglass body vehicles
and antenna mounting (Page 44 of their catalog)
http://www.antenna.com/lm_cat/pdf/lmr_catalog.pdf
Ground Plane Kit Model K-67

Ground plane kit for fiberglass-bodied vehicles. Complete with instructions
and sufficient adhesive backed foil for one low-band/high-band or six UHF
ground planes (3 inches x 44 ft). Includes metal clips for circuit
continuity.

Ground Plane Disk Model K-332

Provides ground plane for fiberglass-bodied vehicles.

THIS NEEDS TO BE ADDED TO THE "BILL of MATERIALS that you are ordering from
the "local company" supplying the radio and antenna materials

=======================================

Greg, w9gb




  #19   Report Post  
Old June 15th 05, 08:26 PM
gb
 
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" wrote in message
oups.com...
Thank you again for your replies.

In the course of conversation with our mechanic this morning on the
matter, I learned that he has mounted a number of the antennas on a
part of the bus that is fiberglass. I tried to explain a bit about
ground-plane to him and the need for the antennas to be mounted on a
metal part of the bus. I' am having him take one of the "worst"
communicating busses and move the antenna to a metal part of the bus. I
am also having him go through all the contacts and connections and
cleaning them. I'll post what was done and what the results have been.

One other point Mike.

After this mechanic installs the COAX and ANTENNA - he can use his VOM to
assure that the center conductor and shield are NOT shorted
(unless you are using a loading coil or other special purpose antenna).
Every mechanic should be very familiar with this test from vehicle
electrical systems.

Greg
w9gb



  #20   Report Post  
Old June 16th 05, 07:44 PM
 
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gb wrote:
Mike -

VERY USEFUL INFORMATION.

Yes, fiberglass is worthless for the required ground plane of a 1/4 wave UHF
antenna - and requires additional materials.
PCTEL based in the Chicago area is a major antenna mfg. and suppliers (e.g.
MAXRAD, Antenna Specialists).

They have 2 suitable products specifically made for fiberglass body vehicles
and antenna mounting (Page 44 of their catalog)
http://www.antenna.com/lm_cat/pdf/lmr_catalog.pdf
Ground Plane Kit Model K-67

Ground plane kit for fiberglass-bodied vehicles. Complete with instructions
and sufficient adhesive backed foil for one low-band/high-band or six UHF
ground planes (3 inches x 44 ft). Includes metal clips for circuit
continuity.

Ground Plane Disk Model K-332

Provides ground plane for fiberglass-bodied vehicles.

THIS NEEDS TO BE ADDED TO THE "BILL of MATERIALS that you are ordering from
the "local company" supplying the radio and antenna materials

=======================================

Greg, w9gb


Thanks, Greg.

I've printed out their catalog and noted the products you suggested.

Yesterday afternoon I had an opportunity to examine our busses more
closely and found a couple different types of antennas in use. Several
look very much like the ASPRD1610 shown in the catalog. The others look
like the ASP-7654, but perhaps with a different base. I have always
understood that when it comes to antennas, the longer they are the
better(in general). The short ones appear to be between 4-6 inches in
length. There is some variation in their lengths. Given their varied
mounting locations on the busses combined with what I learned yesterday
about how things have been done here, I can only assume that very
little is actually "right". At this point, I'm not very confident that
the local supplier pre-cut the antennas, although they may well have. A
phone call will answer that.

As an aside, this particular company appears to make little if any
investment in their people. The manager here must get prior approval
from the regional manager to purchase string for the weed-eater. This
may well help explain why there has been no service contract in place,
nor has there been any attempt to fix the problem(s) with the radios.
This makes me think that other than our remounting the antennas
properly and cleaning connections there may be little we can do.
Perhaps that will be enough to get our communications to a point of
being adequate for our needs.

Anyway, thanks for the information. I'll let you know what we find.

Mike

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