BTW: Which sticks are you in? I'm in EC Indiana, with an
SA that I could loan.
A kind offer, thanks. Different sticks though... I'm in
central Maine, geographically speaking (that's northern
Maine to most of the world :-)
Paul
Yahoo! Groups Links
* To visit your group on the web, go
Title: RE: [Repeater-Builder] UHF Micor (mobile) spur
Paul,
A spur is ususally produced by multiplier circuitry in the transmitter. I would retune the exciter and pay special attention to the position of the slugs prior to retuning. Second you might just have a defective exciter board. Most
Joe was right. I feel like an idiot! But this experience
served as a very effective reminder... I doubt I'll be
making this mistake again any time soon. :-)
Service monitors and spectrum analyzers don't live out here
in the sticks. So when I had reports of a spur I dragged
out my
So it turns out to be the best kind of problem: someone
else's. I'm not sure what we're going to do now... at
least one person will be adversely affected unless I change
repeater frequencies (AGAIN - long story) or he gets a
different radio. At least now I can get these Micors off
my test
Service monitors and spectrum analyzers don't live out here
in the sticks.
BTW: Which sticks are you in? I'm in EC Indiana, with an SA that I could loan.
Yahoo! Groups Links
* To visit your group on the web, go to:
http://groups.yahoo.com/group/Repeater-Builder/
* To unsubscribe
So, no one here has ever run into this before? Really??!
I found and tested a third radio... same problem.
To restate what the problem is: Micor mobile UHF T34...
when running in the ham band transmit low / receive high
they are spurring 910 kHz above the transmit freq. I don't
know what
Paul,
Have you tried using a different instrument to view this spur? Some
spectrum analyzers and service monitors create an artifact of the viewed
signal, due to some unintentional internal mixing. When three different
radios exhibit the same oddball symptom, I'd suspect my test equipment
or
Paul
910 Kc is twice the 455 Kc IF. Possibly there is a clue here. Motorola had
problems with spurs in the Metrum VHF ham transceiver. It also used one
crystal for both transmit and receive. I guess that this is a good data
point as to why mobiles should not be used as repeaters. The repeater
At 10:39 AM 7/2/2005 -0400, you wrote:
So, no one here has ever run into this before? Really??!
To restate what the problem is: Micor mobile UHF T34...
when running in the ham band transmit low / receive high
they are spurring 910 kHz above the transmit freq. I don't
know what would happen
Eric,
Thanks for the reminder never to trust a single instrument
too much. This spur is verifiable though. It can be heard
on the air when the Micors are running into an antenna, up
to at least 5 miles away if it is a true line of sight path
and there is some antenna gain at both ends. And
Thanks Glenn.
When I first noticed the 910 kHz relationship, 455 IF was
the first thing that popped into my mind... until I
realized the Micor doesn't have a 455 kHz IF. Darn,
another good theory ruined...
Since I have 3 similar radios exhibiting exactly the same
problem I am thinking this
On Saturday 02 July 2005 11:57 am, Ken Arck wrote:
---My first reaction is to ask..how are you driving the
xmtr, audio wise? Did you bypass the limiter/filtering?
Thanks Ken.
The spur is there even without audio. But no, I'm not
bypassing anything... controller audio is fed to the
, July 02, 2005 7:39 AM
To: Repeater-Builder@yahoogroups.com
Subject: Re: [Repeater-Builder] UHF Micor (mobile) spur
So, no one here has ever run into this before? Really??!
I found and tested a third radio... same problem.
To restate what the problem is: Micor mobile UHF T34...
when running
At 11:33 AM 7/2/2005, Paul Kelley wrote:
Thanks Glenn.
When I first noticed the 910 kHz relationship, 455 IF was
the first thing that popped into my mind... until I
realized the Micor doesn't have a 455 kHz IF. Darn,
another good theory ruined...
Since I have 3 similar radios exhibiting exactly
--- Glenn Little WB4UIV [EMAIL PROTECTED]
wrote:
Paul
910 Kc is twice the 455 Kc IF. Possibly there is a
clue here. Motorola had
problems with spurs in the Metrum VHF ham
transceiver. It also used one
crystal for both transmit and receive. I guess that
this is a good data
point as
Comments threaded in...
On Saturday 02 July 2005 01:19 pm, Joe Montierth wrote:
I have used lots of Micor mobiles as repeaters and
never seen this problem.
Thanks Joe.
How far down is the spur from the TX carrier?
About 80 dB give or take a bit.
My thought is that the 910KHz is too
I just checked all the radios I've been using to monitor
this spur in-house and all *do* have a 455 kHz IF. I will
have to check the others which may take a day or two. Let
me also see if I can find a receiver which does *not* use a
455 kHz IF to check it with.
The second best kind of problem
was a solid state
PA deck!!)
Obviously, this has noting to do with the subject but is a fun story.
-- Original Message --
Received: Fri, 01 Jul 2005 06:54:32 AM CDT
From: Paul Kelley [EMAIL PROTECTED]
To: Repeater-Builder@yahoogroups.com
Subject: Re: [Repeater-Builder] UHF Micor (mobile) spur
Obviously, this has noting to do with the subject but is a fun story.
I've got one that I'm trying to track down..
A local 2M machine, on 146.730, is having a problem we call the
horrible noise.
I've never heard anything like it, and I've had no success at recording it.
It sounds like some
At 12:07 PM 6/30/05, you wrote:
Aarggh! I've pulled out most of my hair on this one! To
revisit something I asked about several months ago... I'm
still having a problem with my UHF Micor mobile converted
to repeater.
It is a T34RTA3000AA with power set at 20 watts. It is on
444.000 (T),
See below ...
Mike Morris WA6ILQ wrote:
At 12:07 PM 6/30/05, you wrote:
Aarggh! I've pulled out most of my hair on this one! To
revisit something I asked about several months ago... I'm
still having a problem with my UHF Micor mobile converted
to repeater.
It is a T34RTA3000AA
On Friday 01 July 2005 04:56 am, Mike Morris WA6ILQ wrote:
One trick that I have used... the far end of the
preselector tune broader than the near end. I've found
that I get better performance if I do the tuning then
turn it around and tune it again. This lets the old far
end adjustments
I just spent another night poking around in this thing.
Sniffing around the transmitter with a receiver and very
small probe antenna I am reasonably certain the spur is
present at Q305 (exciter mixer) and all subsequent stages.
Using a general coverage receiver the fundamental output of
the
On Friday 01 July 2005 08:43 am, Dave VanHorn wrote:
Any possibility that it's coming from the power supply,
and not actually the amplifier at all?
Do you get it when running from a battery?
Good thought. I tried 3 different power supplies and
finally a battery. There is definitely
At 08:03 AM 7/1/2005, Paul Kelley wrote:
On Friday 01 July 2005 08:43 am, Dave VanHorn wrote:
Any possibility that it's coming from the power supply,
and not actually the amplifier at all?
Do you get it when running from a battery?
Good thought. I tried 3 different power supplies and
Aarggh! I've pulled out most of my hair on this one! To
revisit something I asked about several months ago... I'm
still having a problem with my UHF Micor mobile converted
to repeater.
It is a T34RTA3000AA with power set at 20 watts. It is on
444.000 (T), 449.000 (R) and is producing a
26 matches
Mail list logo