Topics

ATU for mBITX

vu3jyt
 

Hi,I  want to add an antenna tuner for my micro bitx. which is the best?  Manual or Auto or Remote ATU? you suggestions and experiences please.
73,VU3JYT,Rajan

Tom, wb6b
 

If you can find one at a reasonable price a remote ATU would be my first choice. That would be the most efficient place for the tuner to be.

In my case I use the MFJ-939 auto tuner. The main reason is it works independently of any transceiver manufacturer's tuner interface cable and only requires a few watts for the auto-tune to work. I accept the tradeoff of some additional power to the antenna lost through the mismatched coax cable run.

There is another auto-tuner I saw somewhere that only requires about a watt to tune. However, I chose the MFJ because it has a wider match range (that would be valuable in portable use where I'm hooking a long-wire directly to the tuner, and I don't mind being part of the counterpoise), and because it had a high enough power rating that I could use it on other than QRP rigs.

For QRP, there are some really inexpensive manual tuners. Those could be good, too.

Tom, wb6b

 

At 30/08/2018, you wrote:
Hi,I want to add an antenna tuner for my micro bitx. which is the best? Manual or Auto or Remote ATU? you suggestions and experiences please.
73,VU3JYT,Rajan

MVS Sarma
 

i find a cheaper  PVC gangs based  antenna tuner kit as sold by ebay.  For QRP  it should be fine. I know of friends who used  PVC gangs for antenna tuners.
regards
sarma
vu3zmv

On Thu, Aug 30, 2018 at 1:37 PM Raj vu2zap <rajendrakumargg@...> wrote:
What I am using with bitxs

http://www.ldgelectronics.com/c/252/products/21/49/1

Raj


At 30/08/2018, you wrote:
>Hi,I  want to add an antenna tuner for my micro bitx. which is the best?  Manual or Auto or Remote ATU? you suggestions and experiences please.
>73,VU3JYT,Rajan




Lee
 

I use an  LDG Electronics Z-11 Pro auto tuner.  It works very well.. 
-
Lee - N9LO  "I Void Warranties"

 

R. E. Klaus
 

My opinion only, others will have their own. A remote tuner at the antenna is the best choice as it will have the least loss in your coax. as for automatic vs manual, it is mostly personal taste. In some cases a manual tuner may give a better match than an auto tuner but the auto tuner will work well 99.7% of the time.

Bob KB1TEK
 

The Elecraft T1 seems pretty ideal, but I've never used it.  Does anyone else have experience with that tuner?

iz oos
 

If the ATU is close to the antenna I would opt for an auto. If you use the atu close to the rig I would prefer the manual.


Il 30/ago/2018 16:49, "R. E. Klaus via Groups.Io" <reklaus=yahoo.com@groups.io> ha scritto:
My opinion only, others will have their own. A remote tuner at the antenna is the best choice as it will have the least loss in your coax. as for automatic vs manual, it is mostly personal taste. In some cases a manual tuner may give a better match than an auto tuner but the auto tuner will work well 99.7% of the time.


ajparent1/kb1gmx
 

I have a T1 its the ideal pocket sized ATU.  Excellent battery life  I replace
it once a year on general principle..  I believe it can tune a nail on 80m.
For less than 12W its bullet proof L tuner.  It tunes up well even at 1W
and less.  It does so in less than 5 seconds.

One hard note while they rate it for a max of 20W I've blown detector
diodes on 40M for some antenna cases.  Its related to power under
some reactive condition where the voltage at the atu output exceeds
diode tolerance voltage.  It does not show tuning a HW wire at 15W. 
It only takes out one diode of the pair.

That said for under 15W its easy to use and works very well.

I use it with the:
KNQ7A (40M) SSB
Slop bucket 20 SSB
Argonaut 505 (all bands) SSB mostly
Tempo-one QRP tube radio (modified,  12BY7 driver as final about 4-5W)
HB 40M SSB
HB20M SSB
HB15M SSB
HB 10M SSB
Kistandparts 1W CW
WM20  SSB
PSK20 PSK31
FT817 with matching interface cable HF

Allison

Dennis Zabawa
 

I have one of the Chinese tuners, with the plastic, variable capacitors, that I built from a kit.  I found the adjustments to be very touchy and not repeatable.  I have since replaced it with an MFJ-9201, QRP Antenna Tuner.  It is well made and is a lot easier to use than the Chinese, kit tuner.

Peter Parker
 

I would go for a simple manual ATU.  The configuration depending on the antenna being used. 

Some ideas at http://home.alphalink.com.au/~parkerp/projects/projcoupler.htm

73, Peter VK3YE

Tom, wb6b
 

On Thu, Aug 30, 2018 at 09:36 AM, ajparent1/KB1GMX wrote:
T1 its the ideal pocket sized ATU
That's a cool Auto Tuner. Did not realize Elecraft made a reasonable cost Auto ATU. Wonder how hard it would be to hack it, so I could put in in a weather proof box at my antenna and remotely control it?

Tom, wb6b

Tom, wb6b
 

On Fri, Aug 31, 2018 at 04:44 AM, Peter Parker wrote:
I would go for a simple manual ATU.
This may now be my favorite antenna tuner.



Tom, wb6b

iz oos
 

You can't go wrong with it :) how much power can the polyvaricon handle?


Il 31/ago/2018 15:09, "Tom, wb6b" <wb6b@...> ha scritto:
On Fri, Aug 31, 2018 at 04:44 AM, Peter Parker wrote:
I would go for a simple manual ATU.
This may now be my favorite antenna tuner.



Tom, wb6b


W2CTX
 

http://www.elecraft.com/manual/E740079%20T1%20owners%20man%20rev%20B.pdf


There is already a jack to remote control it.  See manual.


rOn

On August 31, 2018 at 8:50 AM "Tom, wb6b" <wb6b@...> wrote:

On Thu, Aug 30, 2018 at 09:36 AM, ajparent1/KB1GMX wrote:
T1 its the ideal pocket sized ATU
That's a cool Auto Tuner. Did not realize Elecraft made a reasonable cost Auto ATU. Wonder how hard it would be to hack it, so I could put in in a weather proof box at my antenna and remotely control it?

Tom, wb6b

Jim Sheldon
 

I've built 3 of them and they remote very easily but you do have to use well shielded cables as any RF pickup tends to mess up the tuning.

Elecraft's software is NOT hackable and is proprietary, not open-source.  

Jim

------ Original Message ------
From: "W2CTX" <w2ctx@...>
Sent: 8/31/2018 10:04:33 AM
Subject: Re: [BITX20] ATU for mBITX

http://www.elecraft.com/manual/E740079%20T1%20owners%20man%20rev%20B.pdf


There is already a jack to remote control it.  See manual.


rOn

On August 31, 2018 at 8:50 AM "Tom, wb6b" <wb6b@...> wrote:

On Thu, Aug 30, 2018 at 09:36 AM, ajparent1/KB1GMX wrote:
T1 its the ideal pocket sized ATU
That's a cool Auto Tuner. Did not realize Elecraft made a reasonable cost Auto ATU. Wonder how hard it would be to hack it, so I could put in in a weather proof box at my antenna and remotely control it?

Tom, wb6b

n5ib_2
 

look at the "Bias Tee" link at <http://qsl.net/n5ib/>
for a way to remote the Elecraft T1 and run power on the coax.

Each of the two Bias Tee units will fit the traditional Altoids tin.
The T1 tuner and its Bias Tee can be fitted into a weatherproof box at the antenna
At the Tx end an SWR meter is needed to monitor/verify the match.

N5IB

Jim Sheldon
 

One other thing on the Elecraft T1 autotuner.  I remember something that Wayne Burdick, N6KR (Elecraft founder and CEO) said about the T1.  During initial testing of it, he messed up and accidentally hit it with 100 watts for a brief period (It's spec'd for 20W CW max) and it survived.  Of course, this isn't recommended but it speaks well for Elecraft's product quality.  

I have one I use regularly in portable ops with rigs other than my KX2 and I built 2 from the kits for others who didn't want to attempt the very close soldering necessary to install the relays in it.  

I've had mine for over 5 years now and it runs just fine.  I had forgotten about N5IB's "bias tee" but that's a really good way to power it remotely.  You still have to use a separate remote cable and that must be well shielded, but you wouldn't have to be checking on the battery all the time.  

The T1 should handle a stock 10-20 watt uBITX with no problem and will match some pretty wierd antenna configurations on many bands.

Jim, W0EB

------ Original Message ------
From: "Jim Sheldon" <w0eb@...>
Sent: 8/31/2018 10:11:15 AM
Subject: Re: [BITX20] ATU for mBITX

I've built 3 of them and they remote very easily but you do have to use well shielded cables as any RF pickup tends to mess up the tuning.

Elecraft's software is NOT hackable and is proprietary, not open-source.  

Jim

------ Original Message ------
From: "W2CTX" <w2ctx@...>
Sent: 8/31/2018 10:04:33 AM
Subject: Re: [BITX20] ATU for mBITX

http://www.elecraft.com/manual/E740079%20T1%20owners%20man%20rev%20B.pdf


There is already a jack to remote control it.  See manual.


rOn

On August 31, 2018 at 8:50 AM "Tom, wb6b" <wb6b@...> wrote:

On Thu, Aug 30, 2018 at 09:36 AM, ajparent1/KB1GMX wrote:
T1 its the ideal pocket sized ATU
That's a cool Auto Tuner. Did not realize Elecraft made a reasonable cost Auto ATU. Wonder how hard it would be to hack it, so I could put in in a weather proof box at my antenna and remotely control it?

Tom, wb6b

n5ib_2
 

The bias tee isn't used to power the T1, since it has internal battery power, and, with latching relays, only draws power when tuning.
The bias tee, using a lithium coin cell for DC power, fires an optical isolator at the antenna end that triggers the remote control line on the T1.

So the only connection between the Tx and the T1 is the coax.

N5IB

Lawrence Galea
 

Google picatune ATU

On Fri, Aug 31, 2018 at 5:46 PM n5ib_2 <n5ib@...> wrote:
The bias tee isn't used to power the T1, since it has internal battery power, and, with latching relays, only draws power when tuning.
The bias tee, using a lithium coin cell for DC power, fires an optical isolator at the antenna end that triggers the remote control line on the T1.

So the only connection between the Tx and the T1 is the coax.

N5IB