Subject: 4 Square Issues
In response to the apparent intermittent issues mentioned, I recently went
through a full Full System analysis/check of my 40M 4 square w/ the help of the
DX Eng tech team. My concern was that I was observing degraded performance
(based on on-air sig repts) in the NW direction & also saw some unusual SWR
readings in the NW direction. The Verticals are homebrew alum 2 in (30 ft) to ½
in extensions, and the 4 phase coax lines and phasing box are from DXE – had
the system up for 10 yrs w/p issues and worked great.
The system check started w/ determining if the issue was in the antennas and/
or the phasing lines. So, here are the steps:
* Disconnected all phasing lines from the antennas and the Box
* Dropped all antennas except one – checked the SWR w/ my MFJ 259 analyzer, and
the repeated for ea of the other three verticals to see if any SWR readings
were bad . . . this also allowed me the opportunity to flush all kinds of junk
(bugs, bird stuff etc) from the tubing and clean up the tubing interfaces; and
also to re-tune ea vertical independently.
* Did the same procedure with the phasing lines connected – read the SWR to ea
of the verticals thru the phasing line to determine if any reading was unusual.
Readings were all OK after both of these steps
* Reconnected all phasing lines to the DXE phasing box and checked SWR from the
transmitter – Still no crazy bad readings!
* So, the DXE tech and I agreed that there was a problem in the Phasing box. I
sent it and they changed out a bunch of bad relays (10 yrs old!), I put it back
on the air and all is well . .. working DX again!
Hope this helps.
73 and Good DX – Alan K9MBQ
-----Original Message-----
From: Mpridesti
Sent: Nov 2, 2021 2:48 PM
To: Jorge Diez - CX6VM
Cc:
Subject: Re: [TowerTalk] 4 SQ issue
Jorge
I am using the Comtek box.
Regards,
Mark, K1RX
> On Nov 2, 2021, at 2:44 PM, Jorge Diez - CX6VM wrote:
>
>
> Hello Mark
>
> what 4SQ box do you use? DXE or homemade?
>
> Sometimes, after several days that I not use my DXE-TFS4, antennas show high
> SWR, I need to TX with high power to return them to low SWR
>
> 73,
> Jorge
> CX6VM/CW5W
>
>> El mar, 2 nov 2021 a las 12:41, Mpridesti via TowerTalk () escribió:
>> My 80 m 4 SQ seems to work well in 3 positions. To the SW the signal drop in
>> the favored direction where the other 3 directions appear to work well.
>>
>> SWR measurements seem normal around 2:1 at the end of the 1/4 wave 75 ohm
>> lines except one which is 1.87. Haven’t made loss measurements yet but I
>> suspect the lowest SWR line is the problem (low reading due to higher than
>> normal loss making it the suspect line).
>>
>> Has anyone else experienced this type of behavior? Also the suspect line is
>> the NW element and the direction which has the problem is SW. Does this make
>> sense? Effectively this lossy element is the other half of the “driven
>> element “ if you thought of the 4 sq as a 3 el vertical beam.
>>
>> Keeping with this concept, one would think the NE direction would have
>> similar loss but it doesn’t (or it’s not noticeable).
>>
>> Regards,
>>
>> Mark, K1RX
>>
>>
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk@contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
> --
> 73,
> Jorge
> CX6VM/CW5W
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|