Come on guys, give Bob a break.
He knows perfectly well what he is doing.
He was only testing the tuner, trying to ascertain its matching ability, not
trying to use the antenna like that.
What he proved is that the tuner can match far more than a built-in tuner
need match.
People who claim their rig's tuner isn't good enough should wake up and fix
their antenna!
If the complaint is that the Eagle's tuner is slow or noisy, that is a fair
complaint.
But it does its job just fine.
(Pepe, I hope you are listening.)
73
Rick, DJ0IP
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Paul Gates
Sent: Saturday, February 09, 2013 2:36 PM
To: Ten Tec
Subject: Re: [TenTec] ATU Performance & Results
Did you have a good reason for using coax?
Paul Gates
> From: RMcGraw@Blomand.net
> To: tentec@contesting.com; TenTec_Eagle@yahoogroups.com
> Date: Thu, 7 Feb 2013 13:38:02 -0600
> Subject: [TenTec] ATU Performance & Results
>
> At risk of stirring the proverbial pot on this subject, I launched into a
morning project of seeing what the internal ATU would handle and investigate
if anything could be done to explain why some get better results than
others.
>
> The antenna used for this test is a center fed 75M dipole some 50 ft high
and having a natural resonance at 3.8 MHz. Center feedpoint has a 1:1
current balun and the feedline is some 75 ft of RG-213. The output of the
radio is connected to a to a suitable cross needle SWR/Power meter via a 1
ft RG-8x jumper. The antenna side of the SWR/Power meter is connected to a
Current Isolator or UNUN being a product from The Wireman item # 8232. This
is basically a coax jumper of some 3 ft in length fitted with a series of
#73 and #43 beads. This jumper is connected via a barrel connector to the
RG-213 feeding the antenna.
>
> It is noted after the initial test and repeating same for reliability, I
found the removal of the Current Isolator between the SWR/Power meter and
the coax to the antenna did cause some noticeable to very large errors in
the value displayed on the external SWR/Power meter. Thus the value
indicated on this meter were affected by circulating current on the coax
feed line. This is not surprising. I have had some suspicion that these
circulating currents may have some effect on the performance of the internal
ATU as well. A point not of concern was the time required to attain a
match as I only check one frequency on each band.
>
> The values shown below are:
> Band.......Frequency........SWR as shown on the radio.........SWR
> value as shown on the external bridge with the Current Isolator in
> place
>
> These values are using the Eagle with its internal tuner:
> 160M..........1942.......No Match......>10:1
> 75M............3900.......1:1...................4:1
> 60M............5357.......1.5:1................8:1
> 40M............7100.......No Match......>10:1
> 30M...........10114.......1:1.................10:1
> 20M...........14325......No Match......>10:1
> 17M...........18135.......1:1................ 10:1
> 15M...........21290.......1.2:1................5:1
> 12M...........24995.......1.5:1................5:1
> 10M...........28402.......1:1...................4:1
>
> These values are using the Omni VII with its internal tuner:
> 160M..........1942........No Match........>10:1
> 75M............3900........1.1:1..................4:1
> 60M............5357........1.5:1..................8:1
> 40M............7100........No match.......>10:1
> 30M...........10114........1.1:1...............10:1
> 20M...........14325........2.5:1.............>10:1
> 17M...........18135........1.1:1...............10:1
> 15M...........21290........1.2:1.................5:1
> 12M...........24995........1.4:1.................5:1
> 10M...........28402........1.5:1.................4:1
>
> So what am I to conclude? The Eagle ATU matched 7 out of 10 bands and the
Omni VII ATU matched 8 out of 10 bands. And the use of the Current Choke or
line isolator does make a difference. I did go back and re-test on 20M and
have no explaination for the difference observed between the two radios
using the same procedure and equipment for measurements.
>
> {I hope these tables stay in alignment}
>
>
> 73
> Bob, K4TAX
>
>
> DISCLOSURE:
> This is to inform all persons, I am a Tentec Ambassador and I receive
compensation according to the Tentec Ambassador program. In addition, I
serve as a volunteer beta test person to Tentec for the Omni VII, Eagle and
Argonaut VI radios. I hold no employment relationship, no financial
interests nor do I conduct any commercial business, direct or indirect, with
Tentec.
>
>
>
>
>
>
>
>
>
>
> .
>
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|