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Re: RU-1:1 UnUn

 

I guess it strikes me odd that you would consider a 1:2.5 SWR into a DUMMY LOAD to be an acceptable result, forgive me if I maintain higher standards. Take a look inside one and tell me it's not shoddily manufactured, wound incorrectly and flapping in the breeze, the core suspended only by the solder joints. Yes, they stuck a thin piece of double-sided tape inside the case but it doesn't even contact the core.

What did I expect? That a simple RF choke not seriously and negatively impact my carefully tuned, resonant antennas.?
Re: RU-1:1 UnUn

 

¿ªÔÆÌåÓý

Heh heh heh ¨C Maxwell and Cebik¡­.. two of my favorite authors.? SWR wasn¡¯t really ¡°a thing¡± until the first solid-state radios that were overly sensitive.

Maxwell has a piece on ¡°Low SWR for the Wrong Reasons¡±.? Low SWR can be the death of an otherwise good antenna.? Once you understand how ¡°Resonance¡± is really measured, you see how SWR is only a number.? When Xc and XL cancel out and X=0 is when the magic starts.

It is getting better.? After about 10 years without an amplifier, I am considering one of the new ones¡­..? The solid-state LD-MOS one I am looking at is 1.5 kW and can stand a 5:1 SWR.? Coax losses can be an issue, which is why all my portable operations run the antenna tuner out where the wire meets the coax.? With well over 10,000 portable contacts ¨C mostly 20-watts and less - in a dozen states and as many countries, something is working.? I can¡¯t see hiking 10 miles (16km) and climbing 3,000+ ft (1,000+ meters) with a 100-watt radio and a huge battery on my back.

SOTA ¨C POTA ¨C Pedestrian Mobile ¨C Camping, it¡¯s all good.





If you look at the Pedestrian Mobile photos, top right photo, there is a white PVC pipe just under the antenna.? That is a 2:1 Un-Un.? Short verticals are usually low Ohmically, on the order of 20-¦¸ to 30¦¸.? Or worse at lower frequencies or shorter whips.? I run 10m ¨C 60m.? The Un-Un makes the antenna look like 40-¦¸ to 60-¦¸.? No tuner needed.

?

?

?

Vy73? ¨C? Mike? ¨C? KD5KC ¨C WRFF851 ¨C? El Paso ¨C Texas? ¨C? DM61rt.?

SOTA W5T-Texas Association Manager.

?

The canyons are calling, colorful and deep.? But I have promises to keep.

And miles to go still in my Jeep...?? And miles to go still in my Jeep...

?

?

ADVENTURE:? The respectful pursuit of trouble.??

An EXIT is really an ENTRANCE to someplace new.?

It isn¡¯t an ADVENTURE until something goes wrong!

?

From: [email protected] <[email protected]> On Behalf Of David Hamm
Sent: Wednesday, April 10, 2024 10:46 AM
To: [email protected]
Subject: Re: [ldgelectronics] RU-1:1 UnUn

?

I guess it strikes me odd that you would consider the characteristics to be of "Shoddy Manufacturing.

?A 2.25 SWR High is not out of line with the Physics involved, as a matter of fact, as a compromise design, it's pretty darn good!

?

I guess it may come down to expectations; what did you expect this UNUN to do for your antenna?

?

Dave WA4WX

?

On Wed, Apr 10, 2024 at 11:54?AM <rainer@...> wrote:

Lawrence,

What ¡°other thread¡± did you post this and got an answer? I see the same behavior and would like to see the response to this.

?

Thanks

Rainer

?

From: [email protected] <[email protected]> On Behalf Of Lawrence KC6WOG
Sent: Wednesday, April 10, 2024 2:39 AM
To: [email protected]
Subject: Re: [ldgelectronics] RU-1:1 UnUn

?

Ryan, in another thread, I posted my SWR sweeps of the RU-1:1 into a dummy load, and now understand why it's behaving strangely with my portable rigs. I believe I'll try rewinding it in the manner you suggest in your video. I assume that's what Vince did with good results. I'm a big fan of LDG and greatly enjoy their tuners, but this is a rather shoddy product! I do like the size and form factor, hopefully rewinding it will do the trick.
Re: RU-1:1 UnUn

 

I guess it strikes me odd that you would consider the characteristics to be of "Shoddy Manufacturing.
?A 2.25 SWR High is not out of line with the Physics involved, as a matter of fact, as a compromise design, it's pretty darn good!

I guess it may come down to expectations; what did you expect this UNUN to do for your antenna?

Dave WA4WX

On Wed, Apr 10, 2024 at 11:54?AM <rainer@...> wrote:

Lawrence,

What ¡°other thread¡± did you post this and got an answer? I see the same behavior and would like to see the response to this.

?

Thanks

Rainer

?

From: [email protected] <[email protected]> On Behalf Of Lawrence KC6WOG
Sent: Wednesday, April 10, 2024 2:39 AM
To: [email protected]
Subject: Re: [ldgelectronics] RU-1:1 UnUn

?

Ryan, in another thread, I posted my SWR sweeps of the RU-1:1 into a dummy load, and now understand why it's behaving strangely with my portable rigs. I believe I'll try rewinding it in the manner you suggest in your video. I assume that's what Vince did with good results. I'm a big fan of LDG and greatly enjoy their tuners, but this is a rather shoddy product! I do like the size and form factor, hopefully rewinding it will do the trick.
Re: RU-1:1 UnUn

 

¿ªÔÆÌåÓý

Lawrence,

What ¡°other thread¡± did you post this and got an answer? I see the same behavior and would like to see the response to this.

?

Thanks

Rainer

?

From: [email protected] <[email protected]> On Behalf Of Lawrence KC6WOG
Sent: Wednesday, April 10, 2024 2:39 AM
To: [email protected]
Subject: Re: [ldgelectronics] RU-1:1 UnUn

?

Ryan, in another thread, I posted my SWR sweeps of the RU-1:1 into a dummy load, and now understand why it's behaving strangely with my portable rigs. I believe I'll try rewinding it in the manner you suggest in your video. I assume that's what Vince did with good results. I'm a big fan of LDG and greatly enjoy their tuners, but this is a rather shoddy product! I do like the size and form factor, hopefully rewinding it will do the trick.
Re: RU-1:1 UnUn

 

Ryan, in another thread, I posted my SWR sweeps of the RU-1:1 into a dummy load, and now understand why it's behaving strangely with my portable rigs. I believe I'll try rewinding it in the manner you suggest in your video. I assume that's what Vince did with good results. I'm a big fan of LDG and greatly enjoy their tuners, but this is a rather shoddy product! I do like the size and form factor, hopefully rewinding it will do the trick.
Re: RU-1:1 UNUN SWR behavior, Is this normal?

 

I just came here to ask this very question! I sometimes run into some RF issues when operating portable with my various antennas, so I picked up an RU-1:1 to see if it would help. It DID greatly reduce the RF issues at the radio end, but I noticed my antennas no longer behaved in the manner I was accustomed to, with some strange SWR issues.

I just now did some tests with a Nano-VNA and and a dummy load. First I swept the HF bands with just the dummy load connected and saw a flat SWR all the way across. Then I inserted the RU-1:1, did the same sweep and saw the SWR gradually rise across the bands, until it hit about 1:2.3 at 30MMz. Clearly this is similar to what Vince was experiencing.

There is a review of the unun on DX-Engineering that complains of the same problem, attributing it to the?ends of the bifilar coil being too close to each other, resulting in higher capacitive coupling between input and output.

Any way you slice it, it's disappointing performance. I'm thinking I'll homebrew something or just run my coax through a big core several times.
Re: Antenna port isolation question.

 

Dwayne thanks very much for your reply, the other day (before your comment) I ran a test using the LDG tuner. I connected my End Fed to the LDG antenna port 1 and my Daiwa meter to TX port. The next test was the End Fed on ant 2 and the Daiwa meter still on antenna 1 port. Both times while transmitting 100 watts into my Hustler vertical I had zero reflective power reading on the Daiwa meter. I tested from 40m to 10m.
Thanks again for the great info.
73
Mike
VE9KK
Had a scare with non working M-1000 meter. Found out cable is fragile

 

I had a little scare with my m-1000 meter this week. 3 months ago I disassembled my shack and put everything in storage to facilitate a shack rebuild? of 40 year old building used as my combination shack/shop. After moving most of it back in I carefully reassembled my station. The M-1000 meter would light up but no response on the meter or button presses. I was going to contact LDG but figured I'd try a new connection cable first. Found one on Amazon and installed it. Problem solved. I have no idea how the cable got damaged. I coiled it up and put it in the box with the tuner. But just a heads up. The cable is apparently pretty fragile but replacements are available from amazon. Of course they are not labeled LDG meter cable. You have to look for a 4 pin Svideo cable. Picked up a gold plated 1 meter one for $9.??
Re: Antenna port isolation question.

 

Mike,

That is a good technical question. Typically, we see about -40db of isolation between antenna ports in LDG tuners. For example, a 100 watt signal will "leak" to the other antenna port about 10 milliwatts. There should be no concern about reflective RF power on the non-transmitting antenna. If the proximity of the two antennas are close, there is probably more energy being coupled through the air than through the tuner.

We would use the -62db number (or better) when there are two or more transceivers connected to the same RF switch.

Best regards,

Dwayne Kincaid
WD8OYG
Re: MC-990 for TS-890?

 

Awesome! Thank you to everyone in the group for your answers and comments, all are appreciated!

Melanie AG4YL
Re: MC-990 for TS-890?

 

Plugged into my TS-890- - works fine, just follow instructions and calibrate the meters using the TS-890 menu system.
All explained in the 890 manual.

W
Re: Balun for ladder line fed multi-band "doublet/dipole" with an Auto Tuner?

 

this is only for my QRP Elecraft KX2. Since I already have them, can I use a 4:1 Voltage balun with a 1:1 choke in series?
--
73
W4NDK
Re: Balun for ladder line fed multi-band "doublet/dipole" with an Auto Tuner?

 

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I have used 4:1 Current BALUNS and 1:1 Current Isolation BALUNS from BALUN Designs for years with great success. ?Have also used DX Engineering branded designs (BALUNS & UNUNS) too, same great success. ?I prefer the BALUN Designs quality and price wise! (Not an ad for them, just my good success using them)

LDG does make some really lightweight BALUNS/UNUNS but I would stay with the larger capacity ones offered by other companies. (3K/5K rated) because impedances are not the same on every band and light duty ones may only be good for 100 watts or less.?
?
Phil Laird, WI5O

On Mar 25, 2024, at 05:31, Nate W4NDK <conchd@...> wrote:

?Hi does LDG make a 4:1 ¡°current¡± Balun?
--
73
W4NDK

Re: Balun for ladder line fed multi-band "doublet/dipole" with an Auto Tuner?

 

I have been using the 4113 from Balun designs for years with my 200 ft doublet. Works great.?
Re: Balun for ladder line fed multi-band "doublet/dipole" with an Auto Tuner?

 

Not that I know of, but I ordered one of these.


It hasn't arrived yet, but several members of my radio club use it and speak highly of it.

73
KC1TEM
Re: MC-990 for TS-890?

 

MSG LDG They will know, i use a DM990 on my TS-990 way better than looking at the radio meters

Mick SA4MDN
Re: Balun for ladder line fed multi-band "doublet/dipole" with an Auto Tuner?

 

Hi does LDG make a 4:1 ¡°current¡± Balun?
--
73
W4NDK
MC-990 for TS-890?

 

I did a search to see if this particular question had been covered before. Most questions that I have found relating to the meters was going to a completely different radio, even within the same brand.

The TS-890 has a meter port at the back, the same as the 990, and I believe that the associated circuitry is the same between the two models.

Does anyone have any experience using the MC-990 with the TS-890? Does anyone know of a reason why it wouldn't work?

Thanks, Melanie AG4YL
Antenna port isolation question.

 

Good afternoon all, I just wanted to pass along some Nanovna measurements I did. I plan to connect my AT-200proII turner to my End Fed antenna to Ant 1 and my Huslter 4BTV to Ant 2. My issue was these antennas are very close and I was concerned about the non-transmitting coax having reflective power on it. With my Nanovna I checked the isolation between Ant 1 and 2 on the tuner and my reading was -36dB at 40m and -24dB at 10m. Ideally -62dB should be considered safe. My question is has anyone else checked the isolation between the antenna ports? Also, I could not find anything in the specs regarding what this measurement should be.
Thanks in advance
Mike
VE9KK
Re: ldg at100 Pro ll

 

Good luck?


On Sat, 16 Mar 2024, 15:53 davebb123456, <davidbrowne76@...> wrote:
Ok great information,
I am waiting on them to?get back to me, as I have a at-1000pro 2 that doesn't work on the meter/pc TTL port, as they now sell them with it switched off, in firmware,
I hope that they will send me the firmware that has not been disabled, as I have a interface for my Kenwood TS 2000 that uses this port to set the tuner,
Dave

On Sat, 16 Mar 2024, 15:28 David Bradley, <bozzbradley@...> wrote:
I did contact LDG ,quick reply they said that the firmware hadn't any issues since its release? but if I have any problems, to reach out to them ,brilliant support,Dave 2E0DTB 73?

On Fri, 15 Mar 2024, 12:01 davebb123456, <davidbrowne76@...> wrote:
Hi no worries,
Dave 2E0DMB?

On Fri, 15 Mar 2024, 11:51 David Bradley, <bozzbradley@...> wrote:
Wow thanks Dave ,for info much appreciated ,Dave 73 2E0DTB

D T Bradley


On Fri, 15 Mar 2024 at 11:21, davebb123456 <davidbrowne76@...> wrote:
Hi David
Yes it can,
Open up your tuner and write down the number on the label on the? IC and go on there website and fill out?the form,
Dave 2E0DMB?

On Fri, 15 Mar 2024, 08:35 David Bradley, <bozzbradley@...> wrote:
Can my above tuners firmware be updated,I wasn't aware that ldg tuners could be updated ,Dave 2E0DTB 73 just curious,TIA

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