Mike,
I have seen the very short refuse to tune cycle on my inverted V with my new
3K as well...I push tune and almost instantly, without going into a cycle I
get a red light. My 746 Pro and LDG tuner would at least go through the
cycle to try and find a match.
73,
Jim / K4ECP
- Original Message -
From: Tim Ellison telli...@itsco.com
To: m...@s3com.net; flexradio@flex-radio.biz
Sent: Saturday, April 25, 2009 7:54 AM
Subject: Re: [Flexradio] Atu malfunction with Flex-3000
Mike,
See my comments below.
-Tim
-Original Message-
From: flexradio-boun...@flex-radio.biz
[mailto:flexradio-boun...@flex-radio.biz] On Behalf Of Mike Schwendeman
Sent: Saturday, April 25, 2009 2:06 AM
To: flexradio@flex-radio.biz
Subject: Re: [Flexradio] Atu malfunction with Flex-3000
Thanks, Dudley;
I will ask a local ham to bring his dummy load over, and I will TEE them
together. (Good idea!) I am surprised that the tuner will (logically)
NOT attempt to tune, if it is looking at a good enough load. (Oh,
well...)
[Tim] It does attempt to tune, that is how it determines what the actual
impedance load is and if it is low (1.1:1) then it bypasses
You had mentioned that your Flex-3000 does not TUNE your dummy load; In
this case, do you get a GREEN ATU button indication i n PowerSDR?
[Tim] No. The green button indicates that the tuner is engaged and it is
compensating for an impedance 1.1:1
My loop antenna is 2 or 3 to one VSWR on 75 meters, for sure. In this
case, I'd expect the tuner to at least ATTEMPT to tune. -Even if it
fails, I mean. (Is this not true?) -For example, if one attaches a load
that has a known 10:1 VSWR, is it correct to assume that the ATU will go
through an ATTEMPT to tune, even if it fails? (Which would take several
seconds.) I would fully expect this to be the operation, as this has been
the case for ALL of the many ATU devices that I have owned. (I have owned
way too many, and all had this predictable try-tune-even-if-fail; -Even my
now-gone SDR-1000's ATU did this!)
In my case, the ATU refuses after an extremely short tune-period!
[Tim] You may need to run the ATU SWR calibration to see what is going on.
This will require a 2.0:1 VSWR load which is two 50 ohm dummy loads in
parallel, or a resistor network that will allow for 50 watts of heat
dissipation for a short amount of time.
-Short tune-period is defined as under one second, which is what I am
seeing. (Only one time, did I see the ATU do a LONG tune-up, resulting in
a GREEN ATU button in PowerSDR. This tune-period took 8 to 10 seconds,
as I recall. This was on my loop antenna, the one with the
2:1 or 3:1 VSWR.)
When I attach my LDG Z-11-Pro to the Flex-3000, it takes several seconds
to tune, as I'd expect. As such, I'd expect the Flex-3000's ATU to at
least go through some gyrations, attempting to tune. -Even if it
fails. This is OK and expected, but it is expected to TRY, from my
experience with a lot of other ATU devices that I have owned.
Thank you for your input.
-Mike-K0JTA
Dudley Hurry wrote:
Mike,
If the SWR is less than 1.2:1 I don't think that the tuner needs to
tune anything and drops out. My dummy load won't tune either, but
doesn't need to. Also my 75 meter does not tune, but it is 1.08:1..
at 3.847,, but at 3.55 it's 3.3:1, but the tuner will re-tune it to
1.1.. Look at it this way, the SW is smart enough not to waste your
time trying to better your match.. One way to check it out is to T
two dummy loads together to create a 2:1 load and try it there..
73,
Dudley
WA5QPZ
Mike Sch. wrote:
Tim; Thank you for your prompt reply! I will add my comments below,
and trim off some the unneeded...
Tim Ellison wrote:
Mike,
See my comments in-line below
-Tim
What I did not know was that the fast tune-up was not a tune-up
after all! (I had interpreted the ATU button (in RED) and the BYP
(in YELLOW) as what I was looking for, in normal operation. On page
58 of the Flex-3000 operator manual, I see that I should see the ATU
in GREEN.
[Tim] If the ATU button turns green, then it was able to match
something better than what you had previously. If not it will be
bypassed.
[Mike] OK on that; I am tuning into a KNOWN GOOD (tested on an IC-756
Pro-II in RTTY and AM modes) dummy load. I have an expected 1:1
match, no reflected on the Icom radio. It was my hope that the ATU
would accept the dummy load that I am using.
I did see the ATU button in GREEN one time only, this on an antenna
that is less than 3:1 VSWR. (This one time event was seen today,
after a few hours of power-OFF for the radio.)
[Tim] The ATU will only tune antennas that are in between 1.1:1 to
3:1
[Mike] My point exactly. I am tuning into (mostly) the MFJ dummy
load. (This should meet the minimum requirements.) I have tried two
different coax cable assemblies, when I have tried to tune the Flex
into the dummy load; -I have this same non-tune into the dummy
