Charlie Tango 11m DX Radio Group Forum
Would you like to react to this message? Create an account in a few clicks or log in to continue.


Welcome to the Charlie Tango DX Group. The home of ALL things Radio - CB, 11m DX, Amateur, PMR446, PLD, Network and Data. We welcome all radio enthusiasts of all knowledge levels. Join today and claim your own unique World Famous CT Call-sign
 
HomeEventsCalendarFAQLatest imagesSearchRegisterLog in
Join in with the fun of the Charlie Tango DX Group Summer 10m Challenge - from April 1st 2024
Navigation
Useful Radio Sites
Log in
Username:
Password:
Log in automatically: 
:: I forgot my password
CT Bill Board





Views This Year
All Time Views
Classified Adverts

Latest topics
» New Member Call Sign Request
MAAS DP-27 dipole antenna tuning Icon_minitimeToday at 11:12 pm by John123

» Southern Area and South Coast SSB Net
MAAS DP-27 dipole antenna tuning Icon_minitimeToday at 8:20 pm by Razz229

» New Member Call Sign Request
MAAS DP-27 dipole antenna tuning Icon_minitimeToday at 3:11 pm by chris stevenson

» Hello and Call-sign Request (Issued)
MAAS DP-27 dipole antenna tuning Icon_minitimeToday at 2:32 pm by Stephen glanvill

» Call sign request (Issued)
MAAS DP-27 dipole antenna tuning Icon_minitimeToday at 10:54 am by Stephen glanvill

» New member - vintage rigs in use?
MAAS DP-27 dipole antenna tuning Icon_minitimeToday at 10:36 am by Miura

» Hello from Milton Keynes
MAAS DP-27 dipole antenna tuning Icon_minitimeYesterday at 10:21 pm by John123

» Call sign request (Issued)
MAAS DP-27 dipole antenna tuning Icon_minitimeYesterday at 9:37 pm by John123

» 10m DXCC Summer Challenge contacts 2024
MAAS DP-27 dipole antenna tuning Icon_minitimeYesterday at 9:25 pm by John H

Keywords
list 2022 power supply ss9900 display Baofeng anytone 2023 software call Sirio lincoln callsign sign president meter ALINCO antenna chart frequency 6900 Mobile Mckinley 9900 yaesu
QRZ Database

 

 MAAS DP-27 dipole antenna tuning

Go down 
+2
Northern Crusader
MrFendt
6 posters
AuthorMessage
MrFendt
New Member
New Member
MrFendt


Call Sign : 29-CT-024
Posts : 32
Times Thanked : 0
Join date : 2020-04-27
QTH or Location : Ireland/Germany
Equipment Used : Team CB/FX mobile & 1.5m orbitor. Sirio HP 4000/Maas DP-27 & Grant 2 premium

MAAS DP-27 dipole antenna tuning Empty
PostSubject: MAAS DP-27 dipole antenna tuning   MAAS DP-27 dipole antenna tuning Icon_minitimeThu Jun 04, 2020 9:15 am

Hello all,

I just bought a Maas DP-27 dipole (Yes yes I know I could have made one etc etc but I had no materials and for the price of this and my time it was definitely easier and cheaper to buy this one). Anyway the quality of the dipole on first impressions is great, with stainless wire and connections and high quality plastic parts. Its a 1/2 wave at about 5m long

MAAS DP-27 dipole antenna tuning Img_6911

MAAS DP-27 dipole antenna tuning Img_6912

MAAS DP-27 dipole antenna tuning Img_6910

MAAS DP-27 dipole antenna tuning Img_6914

MAAS DP-27 dipole antenna tuning Img_6913


So I threw it up last night on my balcony (basically identical to the balcony in the pic from google images) I just left it resting on the timber face and swr'd it, the swr was sky high. I proceeded to shorten it and did get the swr to 1-1.5:1 but i had to shorten it a lot ! (I didn't cut it).

MAAS DP-27 dipole antenna tuning Csm_ge10

My question is, how much should I be shortening it at a time to make a difference ? It was pretty late and I wasn't giving it my absolute best, will be trying again tomorrow but would like some advice, Does it ideally need to be suspended and not lying on a surface ?

I would like to operate from 26.965 MHz - 27.855 MHz predominantly

Cheers & 73,

Mark
Back to top Go down
Northern Crusader
Major contributor
Major contributor



Call Sign : M0GVZ / 26CT1760
Posts : 531
Times Thanked : 35
Join date : 2019-11-13
QTH or Location : IO94SA
Equipment Used : Icom 7300, TS480, President McKinley, Albrecht AE6110, CRT Mike
Age : 53

MAAS DP-27 dipole antenna tuning Empty
PostSubject: Re: MAAS DP-27 dipole antenna tuning   MAAS DP-27 dipole antenna tuning Icon_minitimeFri Jun 05, 2020 5:51 pm

You need to tune it for where it's going to be used so that'll probably mean putting it up and down a fair few times and it's times like this where an antenna analyser becomes worth the money because you can take a reading then adjust it a bit and see how many kHz that amount of adjustment gives you. You can't do this with a SWR meter nearly as well.

Where you had it it'll have been capacitively coupling to loads of stuff, including the house wiring, so will appear electrically longer. You'll find when you move it to where it's going to be installed you're likely to need to lengthen the elements so it was a good job you didn't cut.

Back to top Go down
MrFendt
New Member
New Member
MrFendt


Call Sign : 29-CT-024
Posts : 32
Times Thanked : 0
Join date : 2020-04-27
QTH or Location : Ireland/Germany
Equipment Used : Team CB/FX mobile & 1.5m orbitor. Sirio HP 4000/Maas DP-27 & Grant 2 premium

MAAS DP-27 dipole antenna tuning Empty
PostSubject: Re: MAAS DP-27 dipole antenna tuning   MAAS DP-27 dipole antenna tuning Icon_minitimeSat Jun 06, 2020 2:39 pm

So I stuck the antenna back up today, (in an inverted V due to space) SWR was sky high and gradually shortened it and re tested and was still high until it just dropped off a cliff. Basically 1:1 at both ends of the band. Heard a small bit of chatter on 27.555 but I’m getting some really bad QRM. Not sure if this is because my power supply is about 1.5m away from the radio or just due to the fact that QRM is almost a guarantee in a relatively built up area.
Back to top Go down
Wilko88
New Member
New Member



Call Sign : 26-CT-3558
Posts : 2
Times Thanked : 0
Join date : 2020-05-18
QTH or Location : Bracknell
Equipment Used : None Yet

MAAS DP-27 dipole antenna tuning Empty
PostSubject: Re: MAAS DP-27 dipole antenna tuning   MAAS DP-27 dipole antenna tuning Icon_minitimeSun Jun 07, 2020 8:41 am

Hi - welcome to the world of interference, which is sometimes not a nice place. If you’ve mounted the dipole on a hand rail as in the picture, I’d just try moving it. Pickup from nearby ADSL broadband cables and AC power cables would be my first thought. Re the power supply question - perhaps try bringing the antenna end close to the supply and see if it gets worse and worse. I have also tried a car battery to power the radio and turned the house power off to try to find the noisy thing, if that makes any sense. Happy hunting Smile .
Back to top Go down
MrFendt
New Member
New Member
MrFendt


Call Sign : 29-CT-024
Posts : 32
Times Thanked : 0
Join date : 2020-04-27
QTH or Location : Ireland/Germany
Equipment Used : Team CB/FX mobile & 1.5m orbitor. Sirio HP 4000/Maas DP-27 & Grant 2 premium

MAAS DP-27 dipole antenna tuning Empty
PostSubject: Re: MAAS DP-27 dipole antenna tuning   MAAS DP-27 dipole antenna tuning Icon_minitimeSun Jun 07, 2020 9:14 am

Thanks for the feedback Wilko88. My intention was never to have a permanent homebase as it so easy for me to drive 25 mins and be at ASL 4000ft which is why i'm predominantly static mobile but i did put this up to see if i could have some QSO from home but im not going to put massive effort into eliminating the noise. I will bring the dipole out with me mobile and string it up off a tree so all is not lost.

73's Mark
Back to top Go down
madmax
New Member
New Member
madmax


Call Sign : 13-CT-139
Posts : 24
Times Thanked : 0
Join date : 2023-12-13
QTH or Location : Neustadt, Rhineland-Palatinate, Germany
Equipment Used : Kenwood, Quansheng, CRT SS9900 v4, Dipole
Age : 45

MAAS DP-27 dipole antenna tuning Empty
PostSubject: Re: MAAS DP-27 dipole antenna tuning   MAAS DP-27 dipole antenna tuning Icon_minitimeSat Feb 03, 2024 11:42 pm

I have this antenna recently, and something confuses me about the settings. 
If anyone knows or has experience... Is it allowed to adjust the SWR by shortening or lengthening the ends? 
Or do the ends always need to be the appropriate length for the frequency at which the antenna is used?

The second thing that interests me, if anyone has an idea how to set it up to achieve the best performance for DX... 
My idea was to have it in an inverted V.

Image
Back to top Go down
GaryWilson
CT Directors
CT Directors
GaryWilson


Call Sign : 26-CT-1836 Ham 2E0GGQ
Posts : 4218
Times Thanked : 359
Join date : 2019-06-27
QTH or Location : Redcar, North Yorkshire.
Equipment Used : Radios & Wires & Stuff!
Age : 59

MAAS DP-27 dipole antenna tuning Empty
PostSubject: Re: MAAS DP-27 dipole antenna tuning   MAAS DP-27 dipole antenna tuning Icon_minitimeSun Feb 04, 2024 12:26 am

Hello Dejan,

Yes you will need to lengthen or shorten the legs to tune the antenna to the frequencies that you are using. A dipole should cover the majority of the 11 meter band with an acceptable SWR.

The inverted V configuration will be fine for DX and should also help a bit with local contacts as well.

Best 73 Gary.
Back to top Go down
https://www.qrz.com/db/2E0GGQ
madmax
New Member
New Member
madmax


Call Sign : 13-CT-139
Posts : 24
Times Thanked : 0
Join date : 2023-12-13
QTH or Location : Neustadt, Rhineland-Palatinate, Germany
Equipment Used : Kenwood, Quansheng, CRT SS9900 v4, Dipole
Age : 45

MAAS DP-27 dipole antenna tuning Empty
PostSubject: Re: MAAS DP-27 dipole antenna tuning   MAAS DP-27 dipole antenna tuning Icon_minitimeSun Feb 04, 2024 9:17 pm

GaryWilson wrote:
Hello  Dejan,

Yes you will need to lengthen or shorten the legs to tune the antenna to the frequencies that you are using. A dipole should cover the majority of the 11 meter band with an acceptable SWR.

The inverted V configuration will be fine for DX and should also help a bit with local contacts as well.

Best 73 Gary.
Hello Gary,
Thank you for the comment.
It confused me that it's a bit longer than it should be according to the calculation.


Here is the image, as seen by the Nano VNA:

MAAS DP-27 dipole antenna tuning 20240214
MAAS DP-27 dipole antenna tuning 20240216
MAAS DP-27 dipole antenna tuning 20240215

73's Dejan


Last edited by madmax on Sun Feb 04, 2024 9:58 pm; edited 2 times in total
Back to top Go down
GaryWilson
CT Directors
CT Directors
GaryWilson


Call Sign : 26-CT-1836 Ham 2E0GGQ
Posts : 4218
Times Thanked : 359
Join date : 2019-06-27
QTH or Location : Redcar, North Yorkshire.
Equipment Used : Radios & Wires & Stuff!
Age : 59

MAAS DP-27 dipole antenna tuning Empty
PostSubject: Re: MAAS DP-27 dipole antenna tuning   MAAS DP-27 dipole antenna tuning Icon_minitimeSun Feb 04, 2024 9:31 pm

Hello Dejan,

The legs of an inverted V dipole will need to be a little bit longer than those of a horizontal dipole. If you used a calculator for a horizontal dipole this is why you're experiencing a difference. The height of the ground it's mounted will also effect your results.

Best 73 Gary.

madmax likes this post

Back to top Go down
https://www.qrz.com/db/2E0GGQ
madmax
New Member
New Member
madmax


Call Sign : 13-CT-139
Posts : 24
Times Thanked : 0
Join date : 2023-12-13
QTH or Location : Neustadt, Rhineland-Palatinate, Germany
Equipment Used : Kenwood, Quansheng, CRT SS9900 v4, Dipole
Age : 45

MAAS DP-27 dipole antenna tuning Empty
PostSubject: Re: MAAS DP-27 dipole antenna tuning   MAAS DP-27 dipole antenna tuning Icon_minitimeSun Feb 04, 2024 9:55 pm

GaryWilson wrote:
Hello Dejan,

The legs of an inverted V dipole will need to be a little bit longer than those of a horizontal dipole. If you used a calculator for a horizontal dipole this is why you're experiencing a difference. The height of the ground it's mounted will also effect your results.

Best 73 Gary.
Then everything should be OK

I live on the fourth (last) floor.
I am at an altitude of around 200 meters above sea level.

73's Dejan
Back to top Go down
madmax
New Member
New Member
madmax


Call Sign : 13-CT-139
Posts : 24
Times Thanked : 0
Join date : 2023-12-13
QTH or Location : Neustadt, Rhineland-Palatinate, Germany
Equipment Used : Kenwood, Quansheng, CRT SS9900 v4, Dipole
Age : 45

MAAS DP-27 dipole antenna tuning Empty
PostSubject: Re: MAAS DP-27 dipole antenna tuning   MAAS DP-27 dipole antenna tuning Icon_minitimeMon May 06, 2024 6:23 pm

Short update. 
After just three months of use, I managed to burn out the balun. Very Happy
I wouldn't recommend connecting this antenna to the amplifier.
The balun can barely handle 5 times less power than declared.

John79 likes this post

Back to top Go down
FreqFreak
New Member
New Member
FreqFreak


Posts : 33
Times Thanked : 6
Join date : 2024-01-16
QTH or Location : Lingfield
Equipment Used : CRT Yaesu

MAAS DP-27 dipole antenna tuning Empty
PostSubject: Re: MAAS DP-27 dipole antenna tuning   MAAS DP-27 dipole antenna tuning Icon_minitimeMon May 13, 2024 2:31 pm

I found quite a few bad antennas on Ebay and elsewhere over the years. Often with very thin wiring, and poorly rated small toroids inside.

In the end I made my own with thick copper enameled wire large toroids and soldering by myself which is was good quality.

Some of these ready made dipoles and baluns never achieve get a low SWR. One place uses potting compound for the toriod and wiring which is 100pct unnecessary and that somehow that messes up the SWR, I never saw less than 1.8:1 and all my own baluns and transformers I get 1:1 at the radio.

Then you are likely to get the efficiency and reliability and risk of overheating, any heat is RF that was not radiated. Some hams are trying to make a few bucks on the side form the hobby and they make pure junk.

Frankly it's not good enough so it is worth trying to make your own even if it is just to avoid junk.

I know many hams parrot the saying "1.9 to 1 does not matter etc." The problem is it sets a precedent for other small issues that you are also not meant to worry about. Not elevating the antenna, not using the best coax money can buy, running radio on 80W instead of 100W, not worrying about SWR, not having enough radials, poor soldering and connectors, lossy in line items, not resolving noise sources where possible, poor antennas with crummy patterns on some bands. All these losses then add up. It is a much better approach to try and perfect every part of the station and not let these issues slip. 

Each to their own though.

Power in Watts and RX microvolts lost, are losses plain and simple.

It all adds up in the end, losses and mismatches.
Back to top Go down
Sponsored content





MAAS DP-27 dipole antenna tuning Empty
PostSubject: Re: MAAS DP-27 dipole antenna tuning   MAAS DP-27 dipole antenna tuning Icon_minitime

Back to top Go down
 
MAAS DP-27 dipole antenna tuning
Back to top 
Page 1 of 1
 Similar topics
-
» NVIS 40m Dipole Mobile Whip Antenna
» 11 MTR Mono Band Dipole CB Radio Antenna / Aerial 27.555 MHz
» Wire Dipole Antenna Question.
» Homebrew 2m/70cm Dipole Antenna
» SIRIO SD 27 DIPOLE Antenna . A forgotten Hero

Permissions in this forum:You cannot reply to topics in this forum
Charlie Tango 11m DX Radio Group Forum :: Help and Discussion Forums :: Antenna Discussion-
Jump to: